Programs & Examples On #Rebuild

A failure occurred while executing com.android.build.gradle.internal.tasks

I got this problem when I directly downloaded code files from GitHub but it was showing this error, but my colleague told me to use "Git bash here" and use the command to Gitclone it. After doing so it works fine.

How can I solve the error 'TS2532: Object is possibly 'undefined'?

With the release of TypeScript 3.7, optional chaining (the ? operator) is now officially available.

As such, you can simplify your expression to the following:

const data = change?.after?.data();

You may read more about it from that version's release notes, which cover other interesting features released on that version.

Run the following to install the latest stable release of TypeScript.

npm install typescript

That being said, Optional Chaining can be used alongside Nullish Coalescing to provide a fallback value when dealing with null or undefined values

const data = change?.after?.data() ?? someOtherData();

Xcode 10, Command CodeSign failed with a nonzero exit code

I'm unsure of what causes this issue but one method I used to resolve the porblem successfully was to run pod update on my cocoa pods.

The error (for me anyway) was showing a problem with one of the pods signing. Updating the pods resolved that signing issue.

pod update [PODNAME] //For an individual pod

or

pod update //For all pods.

Hopefully, this will help someone who is having the same "Command CodeSign failed with a nonzero exit code" error.

Xcode couldn't find any provisioning profiles matching

You can get this issue if Apple update their terms. Simply log into your dev account and accept any updated terms and you should be good (you will need to goto Xcode -> project->signing and capabilities and retry the certificate check. This should get you going if terms are the issue.

How to add image in Flutter

Create your assets directory the same as lib level

like this

projectName
 -android
 -ios
 -lib
 -assets
 -pubspec.yaml

then your pubspec.yaml like

  flutter:
  assets:
    - assets/images/

now you can use Image.asset("/assets/images/")

How to clear Flutter's Build cache?

There are basically 3 alternatives to cleaning everything that you could try:

  • flutter clean will delete the /build folder.
  • Manually delete the /build folder, which is essentially the same as flutter clean.
  • Or, as @Rémi Roudsselet pointed out: restart your IDE, as it might be caching some older error logs and locking everything up.

java.lang.RuntimeException: com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex in Android Studio 3.0

I am using Android Studio 3.0 and was facing the same problem. I add this to my gradle:

multiDexEnabled true

And it worked!

Example

android {
    compileSdkVersion 27
    buildToolsVersion '27.0.1'
    defaultConfig {
        applicationId "com.xx.xxx"
        minSdkVersion 15
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        multiDexEnabled true //Add this
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            shrinkResources true
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

And clean the project.

How to clear react-native cache?

For React Native Init approach (without expo) use:

npm start -- --reset-cache

Node - was compiled against a different Node.js version using NODE_MODULE_VERSION 51

Here is what worked for me. I am using looped-back node module with Electron Js and faced this issue. After trying many things following worked for me.

In your package.json file in the scripts add following lines:

  ... 
"scripts": {
        "start": "electron .",
        "rebuild": "electron-rebuild"
    
      },
...

And then run following command npm run rebuild

Node.js: Python not found exception due to node-sass and node-gyp

Hey I got this error resolved by following the steps

  • first I uninstalled python 3.8.6 (latest version)
  • then I installed python 2.7.1 (any Python 2 version will work, but not much older and this is recommended)
  • then I added c:\python27 to environment variables
  • my OS is windows, so I followed this link
  • It worked

EF Core add-migration Build Failed

this is because deleting projects or class libraries from solution and adding projects after deleting with same name. best thing is delete solution file and add projects to it.this works for me (I did this using vsCode)

Setting up Gradle for api 26 (Android)

You could add google() to repositories block

allprojects {
    repositories {
        jcenter()
        maven {
            url 'https://github.com/uPhyca/stetho-realm/raw/master/maven-repo'

        }
        maven {
            url "https://jitpack.io"
        }
        google()
    }
}

Enums in Javascript with ES6

This is my personal approach.

class ColorType {
    static get RED () {
        return "red";
    }

    static get GREEN () {
        return "green";
    }

    static get BLUE () {
        return "blue";
    }
}

// Use case.
const color = Color.create(ColorType.RED);

Rebuild Docker container on file changes

You can run build for a specific service by running docker-compose up --build <service name> where the service name must match how did you call it in your docker-compose file.

Example Let's assume that your docker-compose file contains many services (.net app - database - let's encrypt... etc) and you want to update only the .net app which named as application in docker-compose file. You can then simply run docker-compose up --build application

Extra parameters In case you want to add extra parameters to your command such as -d for running in the background, the parameter must be before the service name: docker-compose up --build -d application

How do I mount a host directory as a volume in docker compose

we have to create your own docker volume mapped with the host directory before we mention in the docker-compose.yml as external

1.Create volume named share

docker volume create --driver local \
--opt type=none \
--opt device=/home/mukundhan/share \
--opt o=bind share

2.Use it in your docker-compose

version: "3"

volumes:
  share:
    external: true

services:
  workstation:
    container_name: "workstation"
    image: "ubuntu"
    stdin_open: true
    tty: true
    volumes:
      - share:/share:consistent
      - ./source:/source:consistent
    working_dir: /source
    ipc: host
    privileged: true
    shm_size: '2gb'
  db:
    container_name: "db"
    image: "ubuntu"
    stdin_open: true
    tty: true
    volumes:
      - share:/share:consistent
    working_dir: /source
    ipc: host

This way we can share the same directory with many services running in different containers

Using filesystem in node.js with async / await

Recommend using an npm package such as https://github.com/davetemplin/async-file, as compared to custom functions. For example:

import * as fs from 'async-file';

await fs.rename('/tmp/hello', '/tmp/world');
await fs.appendFile('message.txt', 'data to append');
await fs.access('/etc/passd', fs.constants.R_OK | fs.constants.W_OK);

var stats = await fs.stat('/tmp/hello', '/tmp/world');

Other answers are outdated

Disable nginx cache for JavaScript files

I have the following nginx virtual host (static content) for local development work to disable all browser caching:

server {
    listen 8080;
    server_name localhost;

    location / {
        root /your/site/public;
        index index.html;

        # kill cache
        add_header Last-Modified $date_gmt;
        add_header Cache-Control 'no-store, no-cache, must-revalidate, proxy-revalidate, max-age=0';
        if_modified_since off;
        expires off;
        etag off;
    }
}

No cache headers sent:

$ curl -I http://localhost:8080
HTTP/1.1 200 OK
Server: nginx/1.12.1
Date: Mon, 24 Jul 2017 16:19:30 GMT
Content-Type: text/html
Content-Length: 2076
Connection: keep-alive
Last-Modified: Monday, 24-Jul-2017 16:19:30 GMT
Cache-Control: no-store
Accept-Ranges: bytes

Last-Modified is always current time.

How to completely uninstall Android Studio from windows(v10)?

First go to android studio folder on location that you installed it ( It’s usually in this path by default ; C:\Program Files\Android\Android Studio, unless you change it when you install Android Studio). Find and run uninstall.exe file.

Wait until uninstallation complete successfully, just few minutes, and after click the close.

To delete any remains of Android Studio setting files, in File Explorer, go to C:\Users\%username%, and delete .android, .AndroidStudio(#version-number) and also .gradle, AndroidStudioProjects if they exist. If you want remain your projects, you’d like to keep AndroidStudioProjects folder.

Then, go to C:\Users\%username%\AppData\Roaming and delete the JetBrains directory.

Note that AppData folder is hidden by default, to make visible it go to view tab and check hidden items in windows8 and10 ( in windows7 Select Folder Options, then select the View tab. Under Advanced settings, select Show hidden files, folders, and drives, and then select OK.

Done, you can remove Android Studio successfully, if you plan to delete SDK tools too, it is enough to remove SDK folder completely.

Node Sass couldn't find a binding for your current environment

Please also remember to rename the xxx.node file ( in my case win32-x64-51) to binding.node and paste in the xxx folder ( in my case win32-x64-51),

react-native :app:installDebug FAILED

Since you are using Mi phone which has MIUI

try this

go to Developer options, scroll down to find 'Turn on MIUI optimization' & disable it. Your Phone will be rebooted

check now


If you are using any other android phone, which has a custom skin/UI on top of android OS, then try disabling the optimization provided by that UI and check.
(usually you can find that in 'Developer options')

How to rebuild docker container in docker-compose.yml?

docker-compose stop nginx # stop if running
docker-compose rm -f nginx # remove without confirmation
docker-compose build nginx # build
docker-compose up -d nginx # create and start in background

Removing container with rm is essential. Without removing, Docker will start old container.

The number of method references in a .dex file cannot exceed 64k API 17

When your app references exceed 65,536 methods, you encounter a build error that indicates your app has reached the limit of the Android build architecture

Multidex support prior to Android 5.0

Versions of the platform prior to Android 5.0 (API level 21) use the Dalvik runtime for executing app code. By default, Dalvik limits apps to a single classes.dex bytecode file per APK. In order to get around this limitation, you can add the multidex support library to your project:

dependencies {
  implementation 'com.android.support:multidex:1.0.3'
}

Multidex support for Android 5.0 and higher

Android 5.0 (API level 21) and higher uses a runtime called ART which natively supports loading multiple DEX files from APK files. Therefore, if your minSdkVersion is 21 or higher, you do not need the multidex support library.

Avoid the 64K limit

  • Remove unused code with ProGuard - Enable code shrinking

Configure multidex in app for

If your minSdkVersion is set to 21 or higher, all you need to do is set multiDexEnabled to true in your module-level build.gradle file

android {
defaultConfig {
    ...
    minSdkVersion 21 
    targetSdkVersion 28
    multiDexEnabled true
  }
 ...
}

if your minSdkVersion is set to 20 or lower, then you must use the multidex support library

android {
defaultConfig {
    ...
    minSdkVersion 15 
    targetSdkVersion 28
    multiDexEnabled true
   }
   ...
}

dependencies {
  compile 'com.android.support:multidex:1.0.3'
}

Override the Application class, change it to extend MultiDexApplication (if possible) as follows:

public class MyApplication extends MultiDexApplication { ... }

add to the manifest file

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.myapp">
    <application
            android:name="MyApplication" >
        ...
    </application>
</manifest>

Resetting a form in Angular 2 after submit

I used in similar case the answer from Günter Zöchbauer, and it was perfect to me, moving the form creation to a function and calling it from ngOnInit().

For illustration, that's how I made it, including the fields initialization:

ngOnInit() {
    // initializing the form model here
    this.createForm();
}

createForm() {
    let EMAIL_REGEXP = /^[^@]+@([^@\.]+\.)+[^@\.]+$/i; // here just to add something more, useful too

    this.userForm = new FormGroup({
        name: new FormControl('', [Validators.required, Validators.minLength(3)]),
        city: new FormControl(''),
        email: new FormControl(null, Validators.pattern(EMAIL_REGEXP))
    });

    this.initializeFormValues();
}

initializeFormValues() {
    const people = {
        name: '',
        city: 'Rio de Janeiro',  // Only for demonstration
        email: ''
    };
    (<FormGroup>this.userForm).setValue(people, { onlySelf: true });
}

resetForm() {
    this.createForm();
    this.submitted = false;
}

I added a button to the form for a smart reset (with the fields initialization):

In the HTML file (or inline template):

<button type="button" [disabled]="userForm.pristine" (click)="resetForm()">Reset</button>

After loading the form at first time or after clicking the reset button we have the following status:

FORM pristine: true 
FORM valid: false (because I have required a field) 
FORM submitted: false
Name pristine: true
City pristine: true
Email pristine: true

And all the field initializations that a simple form.reset() doesn't make for us! :-)

Execution failed for task ':app:processDebugResources' even with latest build tools

I changed the target=android-26 to target=android-23

project.properties

this works great for me.

Android Error Building Signed APK: keystore.jks not found for signing config 'externalOverride'

Click on choose existing and again choose the location where your jks file is located.

enter image description here

I hope this trick works for you.

How to force Docker for a clean build of an image

The command docker build --no-cache . solved our similar problem.

Our Dockerfile was:

RUN apt-get update
RUN apt-get -y install php5-fpm

But should have been:

RUN apt-get update && apt-get -y install php5-fpm

To prevent caching the update and install separately.

See: Best practices for writing Dockerfiles

Android Studio Gradle: Error:Execution failed for task ':app:processDebugGoogleServices'. > No matching client found for package

This exact same error happened to me only when I tried to build my debug build type. The way I solved it was to change my google-services.json for my debug build type. My original field had a field called client_id and the value was android:com.example.exampleapp, and I just deleted the android: prefix and leave as com.example.exampleapp and after that my gradle build was successful.

Hope it helps!

EDIT

I've just added back the android: prefix in my google-services.json and it continued to work correctly. Not sure what happened exactly but I was able to solve my problem with the solution mentioned above.

Android Studio does not show layout preview

I used the Debug "app" button enter image description here
and my problem was solved

A connection was successfully established with the server, but then an error occurred during the login process. (Error Number: 233)

the following points work for me. Try:

  1. start SSMS as administrator
  2. make sure SQL services are running. Change startup type to 'Automatic'

enter image description here

  1. In SSMS, in service instance property table, enable below:

enter image description here

android : Error converting byte to dex

I've noticed this can happen (sometimes) when editing java files while Android Studio is building.

I solved this by manually deleting the build folder and running agin.

Gradle Error:Execution failed for task ':app:processDebugGoogleServices'

Had the same problem i added compile 'com.google.android.gms:play-services-measurement:8.4.0' and deleted apply plugin: 'com.google.gms.google-services' I was using classpath 'com.google.gms:google-services:2.0.0-alpha6' in the build project.

Error: Execution failed for task ':app:clean'. Unable to delete file

react native devs

run

sudo cd android && ./gradlew clean

and if you want release apk

sudo cd android && ./gradlew assembleRelease

Hope it will help someone

Rebuild all indexes in a Database

Also a good script, although my laptop ran out of memory, but this was on a very large table

https://basitaalishan.com/2014/02/23/rebuild-all-indexes-on-all-tables-in-the-sql-server-database/

USE [<mydatabasename>]
Go

--/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
--Arguments             Data Type               Description
--------------          ------------            ------------
--@FillFactor           [int]                   Specifies a percentage that indicates how full the Database Engine should make the leaf level
--                                              of each index page during index creation or alteration. The valid inputs for this parameter
--                                              must be an integer value from 1 to 100 The default is 0.
--                                              For more information, see http://technet.microsoft.com/en-us/library/ms177459.aspx.

--@PadIndex             [varchar](3)            Specifies index padding. The PAD_INDEX option is useful only when FILLFACTOR is specified,
--                                              because PAD_INDEX uses the percentage specified by FILLFACTOR. If the percentage specified
--                                              for FILLFACTOR is not large enough to allow for one row, the Database Engine internally
--                                              overrides the percentage to allow for the minimum. The number of rows on an intermediate
--                                              index page is never less than two, regardless of how low the value of fillfactor. The valid
--                                              inputs for this parameter are ON or OFF. The default is OFF.
--                                              For more information, see http://technet.microsoft.com/en-us/library/ms188783.aspx.

--@SortInTempDB         [varchar](3)            Specifies whether to store temporary sort results in tempdb. The valid inputs for this
--                                              parameter are ON or OFF. The default is OFF.
--                                              For more information, see http://technet.microsoft.com/en-us/library/ms188281.aspx.

--@OnlineRebuild        [varchar](3)            Specifies whether underlying tables and associated indexes are available for queries and data
--                                              modification during the index operation. The valid inputs for this parameter are ON or OFF.
--                                              The default is OFF.
--                                              Note: Online index operations are only available in Enterprise edition of Microsoft
--                                                      SQL Server 2005 and above.
--                                              For more information, see http://technet.microsoft.com/en-us/library/ms191261.aspx.

--@DataCompression      [varchar](4)            Specifies the data compression option for the specified index, partition number, or range of
--                                              partitions. The options  for this parameter are as follows:
--                                                  > NONE - Index or specified partitions are not compressed.
--                                                  > ROW  - Index or specified partitions are compressed by using row compression.
--                                                  > PAGE - Index or specified partitions are compressed by using page compression.
--                                              The default is NONE.
--                                              Note: Data compression feature is only available in Enterprise edition of Microsoft
--                                                      SQL Server 2005 and above.
--                                              For more information about compression, see http://technet.microsoft.com/en-us/library/cc280449.aspx.

--@MaxDOP               [int]                   Overrides the max degree of parallelism configuration option for the duration of the index
--                                              operation. The valid input for this parameter can be between 0 and 64, but should not exceed
--                                              number of processors available to SQL Server.
--                                              For more information, see http://technet.microsoft.com/en-us/library/ms189094.aspx.
--- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -*/

-- Ensure a USE <databasename> statement has been executed first.

SET NOCOUNT ON;

DECLARE  @Version                           [numeric] (18, 10)
        ,@SQLStatementID                    [int]
        ,@CurrentTSQLToExecute              [nvarchar](max)
        ,@FillFactor                        [int]        = 100 -- Change if needed
        ,@PadIndex                          [varchar](3) = N'OFF' -- Change if needed
        ,@SortInTempDB                      [varchar](3) = N'OFF' -- Change if needed
        ,@OnlineRebuild                     [varchar](3) = N'OFF' -- Change if needed
        ,@LOBCompaction                     [varchar](3) = N'ON' -- Change if needed
        ,@DataCompression                   [varchar](4) = N'NONE' -- Change if needed
        ,@MaxDOP                            [int]        = NULL -- Change if needed
        ,@IncludeDataCompressionArgument    [char](1);

IF OBJECT_ID(N'TempDb.dbo.#Work_To_Do') IS NOT NULL
    DROP TABLE #Work_To_Do
CREATE TABLE #Work_To_Do
    (
      [sql_id] [int] IDENTITY(1, 1)
                     PRIMARY KEY ,
      [tsql_text] [varchar](1024) ,
      [completed] [bit]
    )

SET @Version = CAST(LEFT(CAST(SERVERPROPERTY(N'ProductVersion') AS [nvarchar](128)), CHARINDEX('.', CAST(SERVERPROPERTY(N'ProductVersion') AS [nvarchar](128))) - 1) + N'.' + REPLACE(RIGHT(CAST(SERVERPROPERTY(N'ProductVersion') AS [nvarchar](128)), LEN(CAST(SERVERPROPERTY(N'ProductVersion') AS [nvarchar](128))) - CHARINDEX('.', CAST(SERVERPROPERTY(N'ProductVersion') AS [nvarchar](128)))), N'.', N'') AS [numeric](18, 10))

IF @DataCompression IN (N'PAGE', N'ROW', N'NONE')
    AND (
        @Version >= 10.0
        AND SERVERPROPERTY(N'EngineEdition') = 3
        )
BEGIN
    SET @IncludeDataCompressionArgument = N'Y'
END

IF @IncludeDataCompressionArgument IS NULL
BEGIN
    SET @IncludeDataCompressionArgument = N'N'
END

INSERT INTO #Work_To_Do ([tsql_text], [completed])
SELECT 'ALTER INDEX [' + i.[name] + '] ON' + SPACE(1) + QUOTENAME(t2.[TABLE_CATALOG]) + '.' + QUOTENAME(t2.[TABLE_SCHEMA]) + '.' + QUOTENAME(t2.[TABLE_NAME]) + SPACE(1) + 'REBUILD WITH (' + SPACE(1) + + CASE
        WHEN @PadIndex IS NULL
            THEN 'PAD_INDEX =' + SPACE(1) + CASE i.[is_padded]
                    WHEN 1
                        THEN 'ON'
                    WHEN 0
                        THEN 'OFF'
                    END
        ELSE 'PAD_INDEX =' + SPACE(1) + @PadIndex
        END + CASE
        WHEN @FillFactor IS NULL
            THEN ', FILLFACTOR =' + SPACE(1) + CONVERT([varchar](3), REPLACE(i.[fill_factor], 0, 100))
        ELSE ', FILLFACTOR =' + SPACE(1) + CONVERT([varchar](3), @FillFactor)
        END + CASE
        WHEN @SortInTempDB IS NULL
            THEN ''
        ELSE ', SORT_IN_TEMPDB =' + SPACE(1) + @SortInTempDB
        END + CASE
        WHEN @OnlineRebuild IS NULL
            THEN ''
        ELSE ', ONLINE =' + SPACE(1) + @OnlineRebuild
        END + ', STATISTICS_NORECOMPUTE =' + SPACE(1) + CASE st.[no_recompute]
        WHEN 0
            THEN 'OFF'
        WHEN 1
            THEN 'ON'
        END + ', ALLOW_ROW_LOCKS =' + SPACE(1) + CASE i.[allow_row_locks]
        WHEN 0
            THEN 'OFF'
        WHEN 1
            THEN 'ON'
        END + ', ALLOW_PAGE_LOCKS =' + SPACE(1) + CASE i.[allow_page_locks]
        WHEN 0
            THEN 'OFF'
        WHEN 1
            THEN 'ON'
        END + CASE
        WHEN @IncludeDataCompressionArgument = N'Y'
            THEN CASE
                    WHEN @DataCompression IS NULL
                        THEN ''
                    ELSE ', DATA_COMPRESSION =' + SPACE(1) + @DataCompression
                    END
        ELSE ''
        END + CASE
        WHEN @MaxDop IS NULL
            THEN ''
        ELSE ', MAXDOP =' + SPACE(1) + CONVERT([varchar](2), @MaxDOP)
        END + SPACE(1) + ')'
    ,0
FROM [sys].[tables] t1
INNER JOIN [sys].[indexes] i ON t1.[object_id] = i.[object_id]
    AND i.[index_id] > 0
    AND i.[type] IN (1, 2)
INNER JOIN [INFORMATION_SCHEMA].[TABLES] t2 ON t1.[name] = t2.[TABLE_NAME]
    AND t2.[TABLE_TYPE] = 'BASE TABLE'
INNER JOIN [sys].[stats] AS st WITH (NOLOCK) ON st.[object_id] = t1.[object_id]
    AND st.[name] = i.[name]

SELECT @SQLStatementID = MIN([sql_id])
FROM #Work_To_Do
WHERE [completed] = 0

WHILE @SQLStatementID IS NOT NULL
BEGIN
    SELECT @CurrentTSQLToExecute = [tsql_text]
    FROM #Work_To_Do
    WHERE [sql_id] = @SQLStatementID

    PRINT @CurrentTSQLToExecute

    EXEC [sys].[sp_executesql] @CurrentTSQLToExecute

    UPDATE #Work_To_Do
    SET [completed] = 1
    WHERE [sql_id] = @SQLStatementID

    SELECT @SQLStatementID = MIN([sql_id])
    FROM #Work_To_Do
    WHERE [completed] = 0
END

NuGet Packages are missing

For me, the packages were there under the correct path, but the build folders inside the package folder were not. I simply removed all the packages that it said were missing and rebuilt the solution and it successfully created the build folders and the .props files. So the error messages were correct in informing me that something was a miss.

How-to turn off all SSL checks for postman for a specific site

There is an option in Postman if you download it from https://www.getpostman.com instead of the chrome store (most probably it has been introduced in the new versions and the chrome one will be updated later) not sure about the old ones.

In the settings, turn off the SSL certificate verification option enter image description here

Be sure to remember to reactivate it afterwards, this is a security feature.

If you really want to use the chrome app, you could always add an exception to chrome for the url: Enter the url you would like to open in the chrome browser, you'll get a warning with a link at the bottom of the page to add an exception, which if you do, it will also allow postman to access your url. But the first option of using the postman stand-alone app is much better.

I hope this can help.

Impact of Xcode build options "Enable bitcode" Yes/No

From the docs

  • can I use the above method without any negative impact and without compromising a future appstore submission?

Bitcode will allow apple to optimise the app without you having to submit another build. But, you can only enable this feature if all frameworks and apps in the app bundle have this feature enabled. Having it helps, but not having it should not have any negative impact.

  • What does the ENABLE_BITCODE actually do, will it be a non-optional requirement in the future?

For iOS apps, bitcode is the default, but optional. If you provide bitcode, all apps and frameworks in the app bundle need to include bitcode. For watchOS apps, bitcode is required.

  • Are there any performance impacts if I enable / disable it?

The App Store and operating system optimize the installation of iOS and watchOS apps by tailoring app delivery to the capabilities of the user’s particular device, with minimal footprint. This optimization, called app thinning, lets you create apps that use the most device features, occupy minimum disk space, and accommodate future updates that can be applied by Apple. Faster downloads and more space for other apps and content provides a better user experience.

There should not be any performance impacts.

New warnings in iOS 9: "all bitcode will be dropped"

Disclaimer: This is intended for those supporting a continuous integration workflow that require an automated process. If you don't, please use Xcode as described in Javier's answer.

This worked for me to set ENABLE_BITCODE = NO via the command line:

find . -name *project.pbxproj | xargs sed -i -e 's/\(GCC_VERSION = "";\)/\1\ ENABLE_BITCODE = NO;/g'

Note that this is likely to be unstable across Xcode versions. It was tested with Xcode 7.0.1 and as part of a Cordova 4.0 project.

"Multiple definition", "first defined here" errors

You should not include commands.c in your header file. In general, you should not include .c files. Rather, commands.c should include commands.h. As defined here, the C preprocessor is inserting the contents of commands.c into commands.h where the include is. You end up with two definitions of f123 in commands.h.

commands.h

#ifndef COMMANDS_H_
#define COMMANDS_H_

void f123();

#endif

commands.c

#include "commands.h"

void f123()
{
    /* code */
}

Cannot resolve symbol AppCompatActivity - Support v7 libraries aren't recognized?

The best solution is definitely to go to File>Invalidate Caches & Restart

Then in the dialog menu... Click Invalidate Caches & Restart. Wait a minute or however long it takes to reset your project, then you should be good.

--

I should note that I also ran into the issue of referencing a resource file or "R" file that was inside a compileOnly library that I had inside my gradle. (i.e. compileOnly library > res > referenced xml file) I stopped referencing this file in my Java code and it helped me. So be weary of where you are referencing files.

Execution failed for task 'app:mergeDebugResources' Crunching Cruncher....png failed

I had put my images into my drawable folder at the beginning of the project, and it would always give me this error and never build so I:

  1. Deleted everything from drawable
  2. Tried to run (which obviously caused another build error because it's missing a reference to files
  3. Re-added the images to the folder, re-built the project, ran it, and then it worked fine.

I have no idea why this worked for me, but it did. Good luck with this mess we call Android Studio.

What does "Table does not support optimize, doing recreate + analyze instead" mean?

The better option is create a new table copy the rows to the destination table, drop the actual table and rename the newly created table . This method is good for small tables,

How can I rebuild indexes and update stats in MySQL innoDB?

This is done with

ANALYZE TABLE table_name;

Read more about it here.

ANALYZE TABLE analyzes and stores the key distribution for a table. During the analysis, the table is locked with a read lock for MyISAM, BDB, and InnoDB. This statement works with MyISAM, BDB, InnoDB, and NDB tables.

Android java.exe finished with non-zero exit value 1

I've had the same issue just now, and it turned out to be caused by a faulty attrs.xml file in one of my modules. The file initially had two stylable attributes for one of my custom views, but I had deleted one when it turned out I no longer needed it. This was apparently, however, not registered correctly with the IDE and so the build failed when it couldn't find the attribute.

The solution for me was to re-add the attribute, run a clean project after which the build succeeded and I could succesfully remove the attribute again without any further problems.

Hope this helps someone.

how to add picasso library in android studio

Add the Picasso library in Dependency

dependencies {
       ...
       implementation 'com.squareup.picasso:picasso:2.71828'
       ...
    }

Sync The Project Create one imageview in Layout

<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true">
</ImageView>

Add the Internet permission in Manifest file

<uses-permission android:name="android.permission.INTERNET" />

//Initialize ImageView

ImageView imageView = (ImageView) findViewById(R.id.imageView);

//Loading image from below url into imageView

Picasso.get()
   .load("YOUR IMAGE URL HERE")
   .into(imageView);

dyld: Library not loaded: @rpath/libswiftCore.dylib

I am on Xcode 8.3.2. For me the issue was the AppleWWDRCA certificate was in both system and login keychain. Removed both and then added to just login keychain, now it runs fine again. 2 days lost

How to change the version of the 'default gradle wrapper' in IntelliJ IDEA?

In build.gradle add wrapper { gradleVersion = '6.0' }

package android.support.v4.app does not exist ; in Android studio 0.8

tl;dr Remove all unused modules which have a dependency on the support library from your settings.gradle.

Long version:

In our case we had declared the support library as a dependency for all of our modules (one app module and multiple library modules) in a common.gradle file which is imported by every module. However there was one library module which wasn't declared as a dependency for any other module and therefore wasn't build. In every few syncs Android Studio would pick that exact module as the one where to look for the support library (that's why it appeared to happen randomly for us). As this module was never used it never got build which in turn caused the jar file not being in the intermediates folder of the module.

Removing this library module from settings.gradle and syncing again fixed the problem for us.

How to include *.so library in Android Studio?

To use native-library (so files) You need to add some codes in the "build.gradle" file.

This code is for cleaing "armeabi" directory and copying 'so' files into "armeabi" while 'clean project'.

task copyJniLibs(type: Copy) {
    from 'libs/armeabi'
    into 'src/main/jniLibs/armeabi'
}
tasks.withType(JavaCompile) {
    compileTask -> compileTask.dependsOn(copyJniLibs)
}
clean.dependsOn 'cleanCopyJniLibs'

I've been referred from the below. https://gist.github.com/pocmo/6461138

import error: 'No module named' *does* exist

They are several ways to run python script:

  • run by double click on file.py (it opens the python command line)
  • run your file.py from the cmd prompt (cmd) (drag/drop your file on it for instance)
  • run your file.py in your IDE (eg. pyscripter or Pycharm)

Each of these ways can run a different version of python (¤)


Check which python version is run by cmd: Type in cmd:

python --version 

Check which python version is run when clicking on .py:

option 1:

create a test.py containing this:

import sys print (sys.version)
input("exit")

Option 2:

type in cmd:

assoc .py
ftype Python.File

Check the path and if the module (ex: win32clipboard) is recognized in the cmd:

create a test.py containing this:

python
import sys
sys.executable
sys.path
import win32clipboard
win32clipboard.__file__

Check the path and if module is recognized in the .py

create a test.py containing this:

import sys
print(sys.executable)
print(sys.path)
import win32clipboard
print(win32clipboard.__file__)

If the version in cmd is ok but not in .py it's because the default program associated with .py isn't the right one. Change python version for .py

To change the python version associated with cmd:

Control Panel\All Control Panel Items\System\Advanced system setting\Environnement variable In SYSTEM variable set the path variable to you python version (the path are separated by ;: cmd use the FIRST path eg: C:\path\to\Python27;C:\path\to\Python35 ? cmd will use python27)

To change the python version associated with .py extension:

Run cmd as admin:

Write: ftype Python.File="C:\Python35\python.exe" "%1" %* It will set the last python version (eg. python3.6). If your last version is 3.6 but you want 3.5 just add some xxx in your folder (xxxpython36) so it will take the last recognized version which is python3.5 (after the cmd remove the xxx).

Other:

"No modul error" could also come from a syntax error btw python et 3 (eg. missing parenthesis for print function...)

¤ Thus each of them has it's own pip version

Vagrant ssh authentication failure

Mac Solution:

  1. Added local ssh id_rsa key to vagrant private key

    vi /Users//.vagrant/machines/default/virtualbox/private_key

    /Users//.ssh/id_rsa

  2. copied public key /Users//.ssh/id_rsa.pub on vagrant box authorized_keys

ssh vagrant@localhost -p 2222 (password: vagrant) ls -la cd .ssh

  1. chmod 0600 ~/.ssh/authorized_keys

  2. vagrant reload

Problem resolved.

Thanks to

How to copy files from host to Docker container?

Another workaround is using the good old scp. This is useful in the case you need to copy a directory.

From your host run:

scp FILE_PATH_ON_YOUR_HOST IP_CONTAINER:DESTINATION_PATH
scp foo.txt 172.17.0.2:foo.txt

In the case you need to copy a directory:

scp -r DIR_PATH_ON_YOUR_HOST IP_CONTAINER:DESTINATION_PATH
scp -r directory 172.17.0.2:directory

be sure to install ssh into your container too.

apt-get install openssh-server

How to prevent 'query timeout expired'? (SQLNCLI11 error '80040e31')

Turns out that the post (or rather the whole table) was locked by the very same connection that I tried to update the post with.

I had a opened record set of the post that was created by:

Set RecSet = Conn.Execute()

This type of recordset is supposed to be read-only and when I was using MS Access as database it did not lock anything. But apparently this type of record set did lock something on MS SQL Server 2012 because when I added these lines of code before executing the UPDATE SQL statement...

RecSet.Close
Set RecSet = Nothing

...everything worked just fine.

So bottom line is to be careful with opened record sets - even if they are read-only they could lock your table from updates.

How to Display blob (.pdf) in an AngularJS app

A suggestion of code that I just used in my project using AngularJS v1.7.2

$http.get('LabelsPDF?ids=' + ids, { responseType: 'arraybuffer' })
            .then(function (response) {
                var file = new Blob([response.data], { type: 'application/pdf' });
                var fileURL = URL.createObjectURL(file);
                $scope.ContentPDF = $sce.trustAsResourceUrl(fileURL);
            });

<embed ng-src="{{ContentPDF}}" type="application/pdf" class="col-xs-12" style="height:100px; text-align:center;" />

Visual Studio breakpoints not being hit

If anyone is using Visual Studio 2017 and IIS and is trying to debug a web site project, the following worked for me:

  1. Attach the web site project to IIS.
  2. Add it to the solution with File -> Add -> Existing Web Site... and select the project from the inetpub/wwwroot directory.
  3. Right-click on the web site project in the solution explorer and select Property Pages -> Start Options
  4. Click on Specific Page and select the startup page (For service use Service.svc, for web site use Default.aspx or the custom name for the page you selected).
  5. Click on Use custom server and write

http(s)://localhost/(web site name as appears in IIS)

for example: http://localhost/MyWebSite

That's it! Don't forget to make sure the web site is running on the IIS and that the web site you wish to debug is selected as the startup project (Right-click -> Set as StartUp Project).

Original post: How to Debug Your ASP.NET Projects Running Under IIS

NodeJS - Error installing with NPM

Fixed with downgrading Node from v12.8.1 to v11.15.0 and everything installed successfully

npm install doesn't create node_modules directory

If you have a package-lock.json file, you may have to delete that file then run npm i. That worked for me

Android Studio suddenly cannot resolve symbols

I had a much stranger solution. In case anyone runs into this, it's worth double checking your gradle file. It turns out that as I was cloning this git and gradle was runnning, it deleted one line from my build.gradle (app) file.

dependencies {
     provided files(providedFiles)

Obviously the problem here was to just add it back and re-sync with gradle.

Android Gradle plugin 0.7.0: "duplicate files during packaging of APK"

I noticed this commit comment in AOSP, the solution will be to exclude some files using DSL. Probably when 0.7.1 is released.

commit e7669b24c1f23ba457fdee614ef7161b33feee69
Author: Xavier Ducrohet <--->
Date:   Thu Dec 19 10:21:04 2013 -0800

    Add DSL to exclude some files from packaging.

    This only applies to files coming from jar dependencies.
    The DSL is:

    android {
      packagingOptions {
        exclude 'META-INF/LICENSE.txt'
      }
    }

Android Studio says "cannot resolve symbol" but project compiles

I also had this issue with my Android app depending on some of my own Android libraries (using Android Studio 3.0 and 3.1.1).

Whenever I updated a lib and go back to the app, triggering a Gradle Sync, Android Studio was not able to detect the code changes I made to the lib. Compilation worked fine, but Android Studio showed red error lines on some code using the lib.

After investigating, I found that it's because gradle keeps pointing to an old compiled version of my libs. If you go to yourProject/.idea/libraries/ you'll see a list of xml files that contains the link to the compiled version of your libs. These files starts with Gradle__artifacts_*.xml (where * is the name of your libs).

So in order for Android Studio to take the latest version of your libs, you need to delete these Gradle__artifacts_*.xml files, and Android Studio will regenerate them, pointing to the latest compiled version of your libs.

If you don't want to do that manually every time you click on "Gradle sync" (who would want to do that...), you can add this small gradle task in the build.gradle file of your app.

task deleteArtifacts {
    doFirst {
        File librariesFolderPath = file(getProjectDir().absolutePath + "/../.idea/libraries/")
        File[] files = librariesFolderPath.listFiles({ File file -> file.name.startsWith("Gradle__artifacts_") } as FileFilter)

        for (int i = 0; i < files.length; i++) {
            files[i].delete()
        }
    }
}

And in order for your app to always execute this task before doing a gradle sync, you just need to go to the Gradle window, then find the "deleteArtifacts" task under yourApp/Tasks/other/, right click on it and select "Execute Before Sync" (see below).

Gradle window to configure task execution

Now, every time you do a Gradle sync, Android Studio will be forced to use the latest version of your libs.

Changing API level Android Studio

As well as updating the manifest, update the module's build.gradle file too (it's listed in the project pane just below the manifest - if there's no minSdkVersion key in it, you're looking at the wrong one, as there's a couple). A rebuild and things should be fine...

NUnit Unit tests not showing in Test Explorer with Test Adapter installed

If you're using a NUnit3+ version, there is a new Test Adapter available.

Go to "Tools -> Extensions and Updates -> Online" and search for "NUnit3 Test Adapter" and then install.

Default Activity not found in Android Studio

Default Activity name changed (like SplashActivity -> SplashActivity1) and work for me

Integrate ZXing in Android Studio

From version 4.x, only Android SDK 24+ is supported by default, and androidx is required.

Add the following to your build.gradle file:

repositories {
    jcenter()
}

dependencies {
    implementation 'com.journeyapps:zxing-android-embedded:4.1.0'
    implementation 'androidx.appcompat:appcompat:1.0.2'
}

android {
    buildToolsVersion '28.0.3' // Older versions may give compile errors
}

Older SDK versions

For Android SDK versions < 24, you can downgrade zxing:core to 3.3.0 or earlier for Android 14+ support:

repositories {
    jcenter()
}

dependencies {
    implementation('com.journeyapps:zxing-android-embedded:4.1.0') { transitive = false }
    implementation 'androidx.appcompat:appcompat:1.0.2'
    implementation 'com.google.zxing:core:3.3.0'
}

android {
    buildToolsVersion '28.0.3'
}

You'll also need this in your Android manifest:

<uses-sdk tools:overrideLibrary="com.google.zxing.client.android" />

Source : https://github.com/journeyapps/zxing-android-embedded

Visual Studio displaying errors even if projects build

tldr; Unload and reload the problem project.

When this happens to me I (used to) try closing VS and reopen it. That probably worked about half of the time. When it didn't work I would close the solution, delete the .suo file (or the entire .vs folder) and re-open the solution. So far this has always worked for me (more than 10 times in the last 6 months), but it is slightly tedious because some things get reset such as your build mode, startup project, etc.

Since it's usually just one project that's having the problem, I just tried unloading that project and reloading it, and this worked. My sample size is only 1 but it's much faster than the other two options so perhaps worth the attempt. (Update: some of my co-workers have now tried this too, and so far it's worked every time.) I suspect this works because it writes to the .suo file, and perhaps fixes the corrupted part of it that was causing the issue to begin with.

Note: this appears to work for VS 2019, 2017, and 2015.

Where is android studio building my .apk file?

I was having the issue finding my debug apk. Android Studio 0.8.6 did not show the apk or even the output folder at project/project/build/. When I checked the same path project/project/build/ from windows folder explorer, I found the "output" folder there and the debug apk inside it.

Trigger a Travis-CI rebuild without pushing a commit?

I have found another way of forcing re-run CI builds and other triggers:

  1. Run git commit --amend --no-edit without any changes. This will recreate the last commit in the current branch.
  2. git push --force-with-lease origin pr-branch.

Rebuild or regenerate 'ic_launcher.png' from images in Android Studio

Click "File > New > Image Asset"

Asset Type -> Choose -> Image

Browse your image

Set the other properties

Press Next

You will see the 4 different pixel-sizes of your images for use as a launcher-icon

Press Finish !

Building and running app via Gradle and Android Studio is slower than via Eclipse

Just try this first. It is my personal experience.

I had the same problem. What i had done is just permanently disable the antivirus (Mine was Avast Security 2015). Just after disabling the antivirus , thing gone well. the gradle finished successfully. From now within seconds the gradle is finishing ( Only taking 5-10 secs).

Android Studio with Google Play Services

In my case google-play-services_lib are integrate as module (External Libs) for Google map & GCM in my project.

Now, these time require to implement Google Places Autocomplete API but problem is that's code are new and my libs are old so some class not found:

following these steps...

1> Update Google play service into SDK Manager

2> select new .jar file of google play service (Sdk/extras/google/google_play_services/libproject/google-play-services_lib/libs) replace with old one

i got success...!!!

Update select2 data without rebuilding the control

Try this one:

var data = [{id: 1, text: 'First'}, {id: 2, text: 'Second'}, {...}];
$('select[name="my_select"]').empty().select2({
    data: data
});

Cannot find R.layout.activity_main

Thanks to @RubberDuck's comment and @Emil's answer I was able to figure out what the problem was. The IDs of most elements in my XML file were exactly the same. So, I renamed each and every one of them. Also, my XML file contained capital letters. The filename should be in [a-z0-9_] so I renamed my files too and the problem was solved.

System.Collections.Generic.IEnumerable' does not contain any definition for 'ToList'

An alternative to adding LINQ would be to use this code instead:

List<Pax_Detail> paxList = new List<Pax_Detail>(pax);

npm ERR cb() never called

I have the same error in my project. I am working on isolated intranet so my solution was following:

  • run npm clean cache --force
  • delete package-lock.json
  • in my case I had to setup NPM proxy in .npmrc

Running Python on Windows for Node.js dependencies

The following worked for me from the command line as admin:

Installing windows-build-tools (this can take 15-20 minutes):

 npm --add-python-to-path='true' --debug install --global windows-build-tools

Adding/updating the environment variable:

setx PYTHON "%USERPROFILE%\.windows-build-tools\python27\python.exe"

Installing node-gyp:

npm install --global node-gyp

Changing the name of the exe file from Python to Python2.7.

C:\Users\username\.windows-build-tools\python27\Python2.7

npm install module_name --save

OpenCV error: the function is not implemented

If it's giving you errors with gtk, try qt.

sudo apt-get install libqt4-dev
cmake -D WITH_QT=ON ..
make
sudo make install

If this doesn't work, there's an easy way out.

sudo apt-get install libopencv-*

This will download all the required dependencies(although it seems that you have all the required libraries installed, but still you could try it once). This will probably install OpenCV 2.3.1 (Ubuntu 12.04). But since you have OpenCV 2.4.3 in /usr/local/lib include this path in /etc/ld.so.conf and do ldconfig. So now whenever you use OpenCV, you'd use the latest version. This is not the best way to do it but if you're still having problems with qt or gtk, try this once. This should work.

Update - 18th Jun 2019

I got this error on my Ubuntu(18.04.1 LTS) system for openCV 3.4.2, as the method call to cv2.imshow was failing (e.g., at the line of cv2.namedWindow(name) with error: cv2.error: OpenCV(3.4.2). The function is not implemented.). I am using anaconda. Just the below 2 steps helped me resolve:

conda remove opencv
conda install -c conda-forge opencv=4.1.0

If you are using pip, you can try

pip install opencv-contrib-python

Socket File "/var/pgsql_socket/.s.PGSQL.5432" Missing In Mountain Lion (OS X Server)

Check for the status of the database:

service postgresql status

If the database is not running, start the db:

sudo service postgresql start

After updating Entity Framework model, Visual Studio does not see changes

First Build your Project and if it was successful, right click on the "model.tt" file and choose run custom tool. It will fix it.

Again Build your project and point to "model.context.tt" run custom tool. it will update DbSet lists.

VC++ fatal error LNK1168: cannot open filename.exe for writing

Restarting Visual Studio solved the problem for me.

import android packages cannot be resolved

RightClick on the Project > Properties > Android > Fix project properties

This solved it for me. easy.

Could not load file or assembly ... An attempt was made to load a program with an incorrect format (System.BadImageFormatException)

The Chilkat .NET 4.5 assembly requires the VC++ 2012 or 2013 runtime to be installed on any computer where your application runs. Most computers will already have it installed. Your development computer will have it because Visual Studio has been installed. However, if deploying to a computer where the required VC++ runtime is not available, the above error will occur:

Install all of the bellow packages

Visual C++ Redistributable Packages for Visual Studio 2013 - vcredist_x64

Visual C++ Redistributable Packages for Visual Studio 2013 - vcredist_x86

Visual C++ Redistributable Packages for Visual Studio 2012 - vcredist_x64

Visual C++ Redistributable Packages for Visual Studio 2012 - vcredist_x86

NPM clean modules

You can take advantage of the 'npm cache' command which downloads the package tarball and unpacks it into the npm cache directory.

The source can then be copied in.

Using ideas gleaned from https://groups.google.com/forum/?fromgroups=#!topic/npm-/mwLuZZkHkfU I came up with the following node script. No warranties, YMMV, etcetera.

var fs = require('fs'),
path = require('path'),
exec = require('child_process').exec,
util = require('util');

var packageFileName = 'package.json';
var modulesDirName = 'node_modules';
var cacheDirectory = process.cwd();
var npmCacheAddMask = 'npm cache add %s@%s; echo %s';
var sourceDirMask = '%s/%s/%s/package';
var targetDirMask = '%s/node_modules/%s';

function deleteFolder(folder) {
    if (fs.existsSync(folder)) {
        var files = fs.readdirSync(folder);
        files.forEach(function(file) {
            file = folder + "/" + file;
            if (fs.lstatSync(file).isDirectory()) {
                deleteFolder(file);
            } else {
                fs.unlinkSync(file);
            }
        });
        fs.rmdirSync(folder);
    }
}

function downloadSource(folder) {
    var packageFile = path.join(folder, packageFileName);
    if (fs.existsSync(packageFile)) {
        var data = fs.readFileSync(packageFile);
        var package = JSON.parse(data);

        function getVersion(data) {
            var version = data.match(/-([^-]+)\.tgz/);
            return version[1];
        }

        var callback = function(error, stdout, stderr) {
            var dependency = stdout.trim();
            var version = getVersion(stderr);
            var sourceDir = util.format(sourceDirMask, cacheDirectory, dependency, version);
            var targetDir = util.format(targetDirMask, folder, dependency);
            var modulesDir = folder + '/' + modulesDirName;

            if (!fs.existsSync(modulesDir)) {
                fs.mkdirSync(modulesDir);
            }

            fs.renameSync(sourceDir, targetDir);
            deleteFolder(cacheDirectory + '/' + dependency);
            downloadSource(targetDir);
        };

        for (dependency in package.dependencies) {
            var version = package.dependencies[dependency];
            exec(util.format(npmCacheAddMask, dependency, version, dependency), callback);
        }
    }
}

if (!fs.existsSync(path.join(process.cwd(), packageFileName))) {
    console.log(util.format("Unable to find file '%s'.", packageFileName));
    process.exit();
}

deleteFolder(path.join(process.cwd(), modulesDirName));
process.env.npm_config_cache = cacheDirectory;
downloadSource(process.cwd());

Using setattr() in python

Setattr: We use setattr to add an attribute to our class instance. We pass the class instance, the attribute name, and the value. and with getattr we retrive these values

For example

Employee = type("Employee", (object,), dict())

employee = Employee()

# Set salary to 1000
setattr(employee,"salary", 1000 )

# Get the Salary
value = getattr(employee, "salary")

print(value)

'Incorrect SET Options' Error When Building Database Project

I found the solution for this problem:

  1. Go to the Server Properties.
  2. Select the Connections tab.
  3. Check if the ansi_padding option is unchecked.

If file exists then delete the file

You're close, you just need to delete the file before trying to over-write it.

dim infolder: set infolder = fso.GetFolder(IN_PATH)
dim file: for each file in infolder.Files

    dim name: name = file.name
    dim parts: parts = split(name, ".")

    if UBound(parts) = 2 then

       ' file name like a.c.pdf    

        dim newname: newname = parts(0) & "." & parts(2)
        dim newpath: newpath = fso.BuildPath(OUT_PATH, newname)

        ' warning:
        ' if we have source files C:\IN_PATH\ABC.01.PDF, C:\IN_PATH\ABC.02.PDF, ...
        ' only one of them will be saved as D:\OUT_PATH\ABC.PDF

        if fso.FileExists(newpath) then
            fso.DeleteFile newpath
        end if

        file.Move newpath

    end if

next

NuGet Package Restore Not Working

Note you can force package restore to execute by running the following commands in the nuget package manager console

Update-Package -Reinstall

Forces re-installation of everything in the solution.


Update-Package -Reinstall -ProjectName myProj

Forces re-installation of everything in the myProj project.

Note: This is the nuclear option. When using this command you may not get the same versions of the packages you have installed and that could be lead to issues. This is less likely to occur at a project level as opposed to the solution level.

You can use the -safe commandline parameter option to constrain upgrades to newer versions with the same Major and Minor version component. This option was added later and resolves some of the issues mentioned in the comments.

Update-Package -Reinstall -Safe

How do I add my new User Control to the Toolbox or a new Winform?

One user control can't be applied to it ownself. So open another winform and the one will appear in the toolbox.

How to mount the android img file under linux?

Another option would be to use the File Explorer in DDMS (Eclipse SDK), you can see the whole file system there and download/upload files to the desired place. That way you don't have to mount and deal with images. Just remember to set your device as USB debuggable (from Developer Tools)

Increasing Google Chrome's max-connections-per-server limit to more than 6

IE is even worse with 2 connection per domain limit. But I wouldn't rely on fixing client browsers. Even if you have control over them, browsers like chrome will auto update and a future release might behave differently than you expect. I'd focus on solving the problem within your system design.

Your choices are to:

  1. Load the images in sequence so that only 1 or 2 XHR calls are active at a time (use the success event from the previous image to check if there are more images to download and start the next request).

  2. Use sub-domains like serverA.myphotoserver.com and serverB.myphotoserver.com. Each sub domain will have its own pool for connection limits. This means you could have 2 requests going to 5 different sub-domains if you wanted to. The downfall is that the photos will be cached according to these sub-domains. BTW, these don't need to be "mirror" domains, you can just make additional DNS pointers to the exact same website/server. This means you don't have the headache of administrating many servers, just one server with many DNS records.

What causes signal 'SIGILL'?

It means the CPU attempted to execute an instruction it didn't understand. This could be caused by corruption I guess, or maybe it's been compiled for the wrong architecture (in which case I would have thought the O/S would refuse to run the executable). Not entirely sure what the root issue is.

Unable to execute dex: Multiple dex files define Lcom/myapp/R$array;

As others have mentioned, this occurs when you have multiple copies of the same class in your build path - including bin/ in your classpath is one way to guarantee this problem.

For me, this occurred when I had added android-support-v4.jar to my libs/ folder, and somehow eclipse added a second copy to bin/classes/android-support-v4.jar.

Deleting the extra copy in bin/classes solved the problem - unsure why Eclipse made a copy there.

You can test for this with

grep -r YourOffendingClassName YourApp | grep jar

error LNK2038: mismatch detected for '_ITERATOR_DEBUG_LEVEL': value '0' doesn't match value '2' in main.obj

I had the same problem today (VS2010), I built Release | Win32, then tried to build Debug | Win32, and got this message.

I tried cleaning Debug | Win32 but the error still persisted. I then cleaned Release | Win32, then cleaned Debug | Win32, and then it built fine.

How to fix "namespace x already contains a definition for x" error? Happened after converting to VS2010

I had this problem. It was due to me renaming a folder in the App_Code directory and releasing to my iis site folder. The original named folder was still present in my target directory - hence duplicate - (I don't do a full delete of target before copying) Anyway removing the old folder fixed this.

TextView - setting the text size programmatically doesn't seem to work

Please see this link for more information on setting the text size in code. Basically it says:

public void setTextSize (int unit, float size)

Since: API Level 1 Set the default text size to a given unit and value. See TypedValue for the possible dimension units. Related XML Attributes

android:textSize Parameters

unit The desired dimension unit.
size The desired size in the given units.

unable to start mongodb local server

I had the same problem were I tried to open a new instance of mongod and it said it was already running.

I checked the docs and it said to type

mongo
use admin
db.shutdownServer()

Visual Studio: LINK : fatal error LNK1181: cannot open input file

I had the same issue in both VS 2010 and VS 2012. On my system the first static lib was built and then got immediately deleted when the main project started building.

The problem is the common intermediate folder for several projects. Just assign separate intermediate folder for each project.

Read more on this here

What is the difference between OFFLINE and ONLINE index rebuild in SQL Server?

The main differences are:

1) OFFLINE index rebuild is faster than ONLINE rebuild.

2) Extra disk space required during SQL Server online index rebuilds.

3) SQL Server locks acquired with SQL Server online index rebuilds.

  • This schema modification lock blocks all other concurrent access to the table, but it is only held for a very short period of time while the old index is dropped and the statistics updated.

Error while trying to run project: Unable to start program. Cannot find the file specified

I personally have this issue in Visual 2012 with x64 applications when I check the option "Managed C++ Compatibility Mode" of Debugging->General options of Tools->Options menu. => Unchecking this option fixes the problem.

How to change the minSdkVersion of a project?

In your app/build.gradle file, you can set the minSdkVersion inside defaultConfig.

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.3"

    defaultConfig {
        applicationId "com.name.app"
        minSdkVersion 19    // This over here
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }

Error: The type exists in both directories

Try to change folder name

  • from APP_CODE
  • to CODE.

This fixed my issue.

Alternatively you can move to another folder all your code files.

Chart won't update in Excel (2007)

This is an absurd bug that is severely hampering my work with Excel.

Based on the work arounds posted I came to the following actions as the simplist way to move forward...

Click on the graph you want update - Select CTRL-X, CTRL-V to cut and paste the graph in place... it will be forced to update.

Referenced Project gets "lost" at Compile Time

Check your build types of each project under project properties - I bet one or the other will be set to build against .NET XX - Client Profile.

With inconsistent versions, specifically with one being Client Profile and the other not, then it works at design time but fails at compile time. A real gotcha.

There is something funny going on in Visual Studio 2010 for me, which keeps setting projects seemingly randomly to Client Profile, sometimes when I create a project, and sometimes a few days later. Probably some keyboard shortcut I'm accidentally hitting...

Namespace not recognized (even though it is there)

In my case i had copied a classlibrary, and not changed the "Assembly Name" in the project properties, so one DLL was overwriting the other...

How to tell a Mockito mock object to return something different the next time it is called?

First of all don't make the mock static. Make it a private field. Just put your setUp class in the @Before not @BeforeClass. It might be run a bunch, but it's cheap.

Secondly, the way you have it right now is the correct way to get a mock to return something different depending on the test.

Purge or recreate a Ruby on Rails database

I use the following one liner in Terminal.

$ rake db:drop && rake db:create && rake db:migrate && rake db:schema:dump && rake db:test:prepare

I put this as a shell alias and named it remigrate

By now, you can easily "chain" Rails tasks:

$ rake db:drop db:create db:migrate db:schema:dump db:test:prepare # db:test:prepare no longer available since Rails 4.1.0.rc1+

Howto: Clean a mysql InnoDB storage engine?

Here is a more complete answer with regard to InnoDB. It is a bit of a lengthy process, but can be worth the effort.

Keep in mind that /var/lib/mysql/ibdata1 is the busiest file in the InnoDB infrastructure. It normally houses six types of information:

InnoDB Architecture

InnoDB Architecture

Many people create multiple ibdata files hoping for better disk-space management and performance, however that belief is mistaken.

Can I run OPTIMIZE TABLE ?

Unfortunately, running OPTIMIZE TABLE against an InnoDB table stored in the shared table-space file ibdata1 does two things:

  • Makes the table’s data and indexes contiguous inside ibdata1
  • Makes ibdata1 grow because the contiguous data and index pages are appended to ibdata1

You can however, segregate Table Data and Table Indexes from ibdata1 and manage them independently.

Can I run OPTIMIZE TABLE with innodb_file_per_table ?

Suppose you were to add innodb_file_per_table to /etc/my.cnf (my.ini). Can you then just run OPTIMIZE TABLE on all the InnoDB Tables?

Good News : When you run OPTIMIZE TABLE with innodb_file_per_table enabled, this will produce a .ibd file for that table. For example, if you have table mydb.mytable witha datadir of /var/lib/mysql, it will produce the following:

  • /var/lib/mysql/mydb/mytable.frm
  • /var/lib/mysql/mydb/mytable.ibd

The .ibd will contain the Data Pages and Index Pages for that table. Great.

Bad News : All you have done is extract the Data Pages and Index Pages of mydb.mytable from living in ibdata. The data dictionary entry for every table, including mydb.mytable, still remains in the data dictionary (See the Pictorial Representation of ibdata1). YOU CANNOT JUST SIMPLY DELETE ibdata1 AT THIS POINT !!! Please note that ibdata1 has not shrunk at all.

InnoDB Infrastructure Cleanup

To shrink ibdata1 once and for all you must do the following:

  1. Dump (e.g., with mysqldump) all databases into a .sql text file (SQLData.sql is used below)

  2. Drop all databases (except for mysql and information_schema) CAVEAT : As a precaution, please run this script to make absolutely sure you have all user grants in place:

    mkdir /var/lib/mysql_grants
    cp /var/lib/mysql/mysql/* /var/lib/mysql_grants/.
    chown -R mysql:mysql /var/lib/mysql_grants
    
  3. Login to mysql and run SET GLOBAL innodb_fast_shutdown = 0; (This will completely flush all remaining transactional changes from ib_logfile0 and ib_logfile1)

  4. Shutdown MySQL

  5. Add the following lines to /etc/my.cnf (or my.ini on Windows)

    [mysqld]
    innodb_file_per_table
    innodb_flush_method=O_DIRECT
    innodb_log_file_size=1G
    innodb_buffer_pool_size=4G
    

    (Sidenote: Whatever your set for innodb_buffer_pool_size, make sure innodb_log_file_size is 25% of innodb_buffer_pool_size.

    Also: innodb_flush_method=O_DIRECT is not available on Windows)

  6. Delete ibdata* and ib_logfile*, Optionally, you can remove all folders in /var/lib/mysql, except /var/lib/mysql/mysql.

  7. Start MySQL (This will recreate ibdata1 [10MB by default] and ib_logfile0 and ib_logfile1 at 1G each).

  8. Import SQLData.sql

Now, ibdata1 will still grow but only contain table metadata because each InnoDB table will exist outside of ibdata1. ibdata1 will no longer contain InnoDB data and indexes for other tables.

For example, suppose you have an InnoDB table named mydb.mytable. If you look in /var/lib/mysql/mydb, you will see two files representing the table:

  • mytable.frm (Storage Engine Header)
  • mytable.ibd (Table Data and Indexes)

With the innodb_file_per_table option in /etc/my.cnf, you can run OPTIMIZE TABLE mydb.mytable and the file /var/lib/mysql/mydb/mytable.ibd will actually shrink.

I have done this many times in my career as a MySQL DBA. In fact, the first time I did this, I shrank a 50GB ibdata1 file down to only 500MB!

Give it a try. If you have further questions on this, just ask. Trust me; this will work in the short term as well as over the long haul.

CAVEAT

At Step 6, if mysql cannot restart because of the mysql schema begin dropped, look back at Step 2. You made the physical copy of the mysql schema. You can restore it as follows:

mkdir /var/lib/mysql/mysql
cp /var/lib/mysql_grants/* /var/lib/mysql/mysql
chown -R mysql:mysql /var/lib/mysql/mysql

Go back to Step 6 and continue

UPDATE 2013-06-04 11:13 EDT

With regard to setting innodb_log_file_size to 25% of innodb_buffer_pool_size in Step 5, that's blanket rule is rather old school.

Back on July 03, 2006, Percona had a nice article why to choose a proper innodb_log_file_size. Later, on Nov 21, 2008, Percona followed up with another article on how to calculate the proper size based on peak workload keeping one hour's worth of changes.

I have since written posts in the DBA StackExchange about calculating the log size and where I referenced those two Percona articles.

Personally, I would still go with the 25% rule for an initial setup. Then, as the workload can more accurate be determined over time in production, you could resize the logs during a maintenance cycle in just minutes.

What is a PDB file?

I had originally asked myself the question "Do I need a PDB file deployed to my customer's machine?", and after reading this post, decided to exclude the file.

Everything worked fine, until today, when I was trying to figure out why a message box containing an Exception.StackTrace was missing the file and line number information - necessary for troubleshooting the exception. I re-read this post and found the key nugget of information: that although the PDB is not necessary for the app to run, it is necessary for the file and line numbers to be present in the StackTrace string. I included the PDB file in the executable folder and now all is fine.

How do I specify the platform for MSBuild?

In Visual Studio 2019, version 16.8.4, you can just add

<Prefer32Bit>false</Prefer32Bit>

Difference between Build Solution, Rebuild Solution, and Clean Solution in Visual Studio?

I just think of Rebuild as performing the Clean first followed by the Build. Perhaps I am wrong ... comments?

Visual Studio build fails: unable to copy exe-file from obj\debug to bin\debug

I faced the same error.

I solved the problem by deleting all the contents of bin folders of all the dependent projects/libraries.

This error mainly happens due to version changes.

Truncating all tables in a Postgres database

Could you use dynamic SQL to execute each statement in turn? You would probably have to write a PL/pgSQL script to do this.

http://www.postgresql.org/docs/8.3/static/plpgsql-statements.html (section 38.5.4. Executing Dynamic Commands)

Visual Studio 2010 always thinks project is out of date, but nothing has changed

I've deleted a cpp and some header files from the solution (and from the disk) but still had the problem.

Thing is, every file the compiler uses goes in a *.tlog file in your temp directory. When you remove a file, this *.tlog file is not updated. That's the file used by incremental builds to check if your project is up to date.

Either edit this .tlog file manually or clean your project and rebuild.

Xcode "Build and Archive" from command line

try xctool, it is a replacement for Apple's xcodebuild that makes it easier to build and test iOS and Mac products. It's especially helpful for continuous integration. It has a few extra features:

  1. Runs the same tests as Xcode.app.
  2. Structured output of build and test results.
  3. Human-friendly, ANSI-colored output.

No.3 is extremely useful. I don't if anyone can read the console output of xcodebuild, I can't, usually it gave me one line with 5000+ characters. Even harder to read than a thesis paper.

xctool: https://github.com/facebook/xctool

NoClassDefFoundError - Eclipse and Android

Same thing worked for me: Properties -> Java Build Path -> "Order and Export" Interestingly - why this is not done automatically? I guess some setting is missing. Also this happened for me after SDK upgrade.

Parser Error: '_Default' is not allowed here because it does not extend class 'System.Web.UI.Page' & MasterType declaration

I figured it out. The problem was that there were still some pages in the project that hadn't been converted to use "namespaces" as needed in a web application project. I guess I thought that it wouldn't compile if there were still any of those pages around, but if the page didn't reference anything from outside itself it didn't appear to squawk. So when it was saying that it didn't inherit from "System.Web.UI.Page" that was because it couldn't actually find the class "BasePage" at run time because the page itself was not in the WebApplication namespace. I went through all my pages one by one and made sure that they were properly added to the WebApplication namespace and now it not only compiles without issue, it also displays normally. yay!

what a trial converting from website to web application project can be!

Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine

Change in IIS Settings application pool advanced settings.Enable 32 bit application

Codesign error: Provisioning profile cannot be found after deleting expired profile

You Could remove old reference of provisioning file. Then after import new provisioning Profile and selecting Xcode builder.

Disable all gcc warnings

-w is the GCC-wide option to disable warning messages.

MSBuild doesn't copy references (DLL files) if using project dependencies in solution

The issue I was facing was I have a project that is dependent on a library project. In order to build I was following these steps:

msbuild.exe myproject.vbproj /T:Rebuild
msbuild.exe myproject.vbproj /T:Package

That of course meant I was missing my library's dll files in bin and most importantly in the package zip file. I found this works perfectly:

msbuild.exe myproject.vbproj /T:Rebuild;Package

I have no idea why this work or why it didn't in the first place. But hope that helps.

Java: Unresolved compilation problem

Make sure you have removed unavailable libraries (jar files) from build path

How do I turn off Oracle password expiration?

To alter the password expiry policy for a certain user profile in Oracle first check which profile the user is using:

select profile from DBA_USERS where username = '<username>';

Then you can change the limit to never expire using:

alter profile <profile_name> limit password_life_time UNLIMITED;

If you want to previously check the limit you may use:

select resource_name,limit from dba_profiles where profile='<profile_name>';

Script for rebuilding and reindexing the fragmented index?

Two solutions: One simple and one more advanced.

Introduction

There are two solutions available to you depending on the severity of your issue

Replace with your own values, as follows:

  • Replace XXXMYINDEXXXX with the name of an index.
  • Replace XXXMYTABLEXXX with the name of a table.
  • Replace XXXDATABASENAMEXXX with the name of a database.

Solution 1. Indexing

Rebuild all indexes for a table in offline mode

ALTER INDEX ALL ON XXXMYTABLEXXX REBUILD

Rebuild one specified index for a table in offline mode

ALTER INDEX XXXMYINDEXXXX ON XXXMYTABLEXXX REBUILD

Solution 2. Fragmentation

Fragmentation is an issue in tables that regularly have entries both added and removed.

Check fragmentation percentage

SELECT  
    ips.[index_id] ,
    idx.[name] ,
    ips.[avg_fragmentation_in_percent]
FROM    
    sys.dm_db_index_physical_stats(DB_ID(N'XXXMYDATABASEXXX'), OBJECT_ID(N'XXXMYTABLEXXX'), NULL, NULL, NULL) AS [ips]
    INNER JOIN sys.indexes AS [idx] ON [ips].[object_id] = [idx].[object_id] AND [ips].[index_id] = [idx].[index_id]

Fragmentation 5..30%

If the fragmentation value is greater than 5%, but less than 30% then it is worth reorganising indexes.

Reorganise all indexes for a table

ALTER INDEX ALL ON XXXMYTABLEXXX REORGANIZE

Reorganise one specified index for a table

ALTER INDEX XXXMYINDEXXXX ON XXXMYTABLEXXX REORGANIZE

Fragmentation 30%+

If the fragmentation value is 30% or greater then it is worth rebuilding then indexes in online mode.

Rebuild all indexes in online mode for a table

ALTER INDEX ALL ON XXXMYTABLEXXX REBUILD WITH (ONLINE = ON)

Rebuild one specified index in online mode for a table

ALTER INDEX XXXMYINDEXXXX ON XXXMYTABLEXXX REBUILD WITH (ONLINE = ON)

Can I restore a single table from a full mysql mysqldump file?

The chunks of SQL are blocked off with "Table structure for table my_table" and "Dumping data for table my_table."

You can use a Windows command line as follows to get the line numbers for the various sections. Adjust the searched string as needed.

find /n "for table `" sql.txt

The following will be returned:

---------- SQL.TXT

[4384]-- Table structure for table my_table

[4500]-- Dumping data for table my_table

[4514]-- Table structure for table some_other_table

... etc.

That gets you the line numbers you need... now, if I only knew how to use them... investigating.

How do you force a makefile to rebuild a target

It was already mentioned, but thought I could add to using touch

If you touch all the source files to be compiled, the touch command changes the timestamps of a file to the system time the touch command was executed.

The source file timstamp is what make uses to "know" a file has changed, and needs to be re-compiled

For example: If the project was a c++ project, then do touch *.cpp, then run make again, and make should recompile the entire project.

I want to delete all bin and obj folders to force all projects to rebuild everything

I actually hate obj files littering the source trees. I usually setup projects so that they output obj files outside source tree. For C# projects I usually use

 <IntermediateOutputPath>..\..\obj\$(AssemblyName)\$(Configuration)\</IntermediateOutputPath>

For C++ projects

 IntermediateDirectory="..\..\obj\$(ProjectName)\$(ConfigurationName)"

Unable to open project... cannot be opened because the project file cannot be parsed

I faced the same problem recently when trying to merge my branch with a remote branch. However, none of the above solutions seemed appropriate to my problem.

There were no merge conflicts between the project.pbxproj file in my branch or the remote branch. However, my projectName.xcodeproj file would refuse to open for the same reason as shown in the asked question.

My solution was to look through the project.pbxproj using a text editor and find if there were any irregularities in the file syntax (for e.g. an extra curly bracket). I sped this process up by focusing on the lines which were inserted or deleted in old file as compared to the merged file. On closer examination, I found the cause of my problem was the repetition of the following line :

xxxxxxxxxxxxx /* [CP] Check Pods Manifest.lock */ = {

in my merged file. This led to an unclosed curly bracket and consequent invalid pbxproj syntax. Deleting the above line fixed my problem.

How do you truncate all tables in a database using TSQL?

Truncating all of the tables will only work if you don't have any foreign key relationships between your tables, as SQL Server will not allow you to truncate a table with a foreign key.

An alternative to this is to determine the tables with foreign keys and delete from these first, you can then truncate the tables without foreign keys afterwards.

See http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=65341 and http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=72957 for further details.

Dropping a connected user from an Oracle 10g database schema

Have you tried ALTER SYSTEM KILL SESSION? Get the SID and SERIAL# from V$SESSION for each session in the given schema, then do

ALTER SCHEMA KILL SESSION sid,serial#;

Convert DateTime to TimeSpan

Try the following code.

 TimeSpan CurrentTime = DateTime.Now.TimeOfDay;

Get the time of the day and assign it to TimeSpan variable.

How to Define Callbacks in Android?

to clarify a bit on dragon's answer (since it took me a while to figure out what to do with Handler.Callback):

Handler can be used to execute callbacks in the current or another thread, by passing it Messages. the Message holds data to be used from the callback. a Handler.Callback can be passed to the constructor of Handler in order to avoid extending Handler directly. thus, to execute some code via callback from the current thread:

Message message = new Message();
<set data to be passed to callback - eg message.obj, message.arg1 etc - here>

Callback callback = new Callback() {
    public boolean handleMessage(Message msg) {
        <code to be executed during callback>
    }
};

Handler handler = new Handler(callback);
handler.sendMessage(message);

EDIT: just realized there's a better way to get the same result (minus control of exactly when to execute the callback):

post(new Runnable() {
    @Override
    public void run() {
        <code to be executed during callback>
    }
});

How to get the selected radio button value using js

Use:

document.querySelector('#elementId:checked').value;

This will return the value of the selected radio button.

Finding even or odd ID values

ID % 2 is checking what the remainder is if you divide ID by 2. If you divide an even number by 2 it will always have a remainder of 0. Any other number (odd) will result in a non-zero value. Which is what is checking for.

Cannot assign requested address using ServerSocket.socketBind

java.net.BindException: Cannot assign requested address

According to BindException documentation, it basically:

Signals that an error occurred while attempting to bind a socket to a local address and port. Typically, the port is in use, or the requested local address could not be assigned.

So try the following command:

sudo lsof -i:8983

to double check if any application is using the same port and kill it.

If that's not the case, make sure that your IP address to which you're trying to bind is correct (it's correctly assigned to your network interface).

AngularJS : ng-click not working

Just add the function reference to the $scope in the controller:

for example if you want the function MyFunction to work in ng-click just add to the controller:

app.controller("MyController", ["$scope", function($scope) {
   $scope.MyFunction = MyFunction;
}]);

Copy Image from Remote Server Over HTTP

For those who need to preserve the original filename and extension

$origin = 'http://example.com/image.jpg';

$filename = pathinfo($origin, PATHINFO_FILENAME);
$ext = pathinfo($origin, PATHINFO_EXTENSION);

$dest = 'myfolder/' . $filename . '.' . $ext;

copy($origin, $dest);

Twitter Bootstrap Multilevel Dropdown Menu

Updated Answer

* Updated answer which support the v2.1.1** bootstrap version stylesheet.

**But be careful because this solution has been removed from v3

Just wanted to point out that this solution is not needed anymore as the latest bootstrap now supports multi-level dropdowns by default. You can still use it if you're on older versions but for those who updated to the latest (v2.1.1 at the time of writing) it is not needed anymore. Here is a fiddle with the updated default multi-level dropdown straight from the documentation:

http://jsfiddle.net/2Smgv/2858/


Original Answer

There have been some issues raised on submenu support over at github and they are usually closed by the bootstrap developers, such as this one, so i think it is left to the developers using the bootstrap to work something out. Here is a demo i put together showing you how you can hack together a working sub-menu.

Relevant code

CSS

.dropdown-menu .sub-menu {
    left: 100%;
    position: absolute;
    top: 0;
    visibility: hidden;
    margin-top: -1px;
}

.dropdown-menu li:hover .sub-menu {
    visibility: visible;
    display: block;
}

.navbar .sub-menu:before {
    border-bottom: 7px solid transparent;
    border-left: none;
    border-right: 7px solid rgba(0, 0, 0, 0.2);
    border-top: 7px solid transparent;
    left: -7px;
    top: 10px;
}
.navbar .sub-menu:after {
    border-top: 6px solid transparent;
    border-left: none;
    border-right: 6px solid #fff;
    border-bottom: 6px solid transparent;
    left: 10px;
    top: 11px;
    left: -6px;
}

Created my own .sub-menu class to apply to the 2-level drop down menus, this way we can position them next to our menu items. Also modified the arrow to display it on the left of the submenu group.

Demo

PHP 7: Missing VCRUNTIME140.dll

I had the same issue, I changed the ports, restarted the services but in vein, only worked for me when I updated the Microsoft Visual c++ filesFrom There yoy can modify MVC

Force browser to refresh css, javascript, etc

Make sure this isn't happening from your DNS. For example Cloudflare has it where you can turn on development mode where it forces a purge on your stylesheets and images as Cloudflare offers accelerated cache. This will disable it and force it to update everytime someone visits your site.

Is ini_set('max_execution_time', 0) a bad idea?

At the risk of irritating you;

You're asking the wrong question. You don't need a reason NOT to deviate from the defaults, but the other way around. You need a reason to do so. Timeouts are absolutely essential when running a web server and to disable that setting without a reason is inherently contrary to good practice, even if it's running on a web server that happens to have a timeout directive of its own.

Now, as for the real answer; probably it doesn't matter at all in this particular case, but it's bad practice to go by the setting of a separate system. What if the script is later run on a different server with a different timeout? If you can safely say that it will never happen, fine, but good practice is largely about accounting for seemingly unlikely events and not unnecessarily tying together the settings and functionality of completely different systems. The dismissal of such principles is responsible for a lot of pointless incompatibilities in the software world. Almost every time, they are unforeseen.

What if the web server later is set to run some other runtime environment which only inherits the timeout setting from the web server? Let's say for instance that you later need a 15-year-old CGI program written in C++ by someone who moved to a different continent, that has no idea of any timeout except the web server's. That might result in the timeout needing to be changed and because PHP is pointlessly relying on the web server's timeout instead of its own, that may cause problems for the PHP script. Or the other way around, that you need a lesser web server timeout for some reason, but PHP still needs to have it higher.

It's just not a good idea to tie the PHP functionality to the web server because the web server and PHP are responsible for different roles and should be kept as functionally separate as possible. When the PHP side needs more processing time, it should be a setting in PHP simply because it's relevant to PHP, not necessarily everything else on the web server.

In short, it's just unnecessarily conflating the matter when there is no need to.

Last but not least, 'stillstanding' is right; you should at least rather use set_time_limit() than ini_set().

Hope this wasn't too patronizing and irritating. Like I said, probably it's fine under your specific circumstances, but it's good practice to not assume your circumstances to be the One True Circumstance. That's all. :)

Delete newline in Vim

All of the following assume that your cursor is on the first line:

Using normal mappings:

3Shift+J

Using Ex commands:

:,+2j

Which is an abbreviation of

:.,.+2 join

Which can also be entered by the following shortcut:

3:j

An even shorter Ex command:

:j3

Adding value to input field with jQuery

You can simply use

 $(this).prev().val("hello world");

JSFiddle Demo

Angular 2: How to style host element of the component?

Check out this issue. I think the bug will be resolved when new template precompilation logic will be implemented. For now I think the best you can do is to wrap your template into <div class="root"> and style this div:

@Component({ ... })
@View({
  template: `
    <div class="root">
      <h2>Hello Angular2!</h2>
      <p>here is your template</p>
    </div>
  `,
  styles: [`
    .root {
      background: blue;
    }
  `],
   ...
})
class SomeComponent {}

See this plunker

Preventing console window from closing on Visual Studio C/C++ Console application

Currently there is no way to do this with apps running in WSL2. However there are two work-arounds:

  1. The debug window retains the contents of the WSL shell window that closed.

  2. The window remains open if your application returns a non-zero return code, so you could return non-zero in debug builds for example.

How do I create a URL shortener?

I have a variant of the problem, in that I store web pages from many different authors and need to prevent discovery of pages by guesswork. So my short URLs add a couple of extra digits to the Base-62 string for the page number. These extra digits are generated from information in the page record itself and they ensure that only 1 in 3844 URLs are valid (assuming 2-digit Base-62). You can see an outline description at http://mgscan.com/MBWL.

remove space between paragraph and unordered list

Every browser has some default styles that apply to a number of HTML elements, likes p and ul. The space you mention is likely created because of the default margin and padding of your browser. You can reset these though:

p { margin: 0; padding: 0; }
ul { margin: 0; padding: 0; }

You could also reset all default margins and paddings:

* { margin: 0; padding: 0; }

I suggest you take a look at normalize.css: http://necolas.github.com/normalize.css/

Updating property value in properties file without deleting other values

Properties prop = new Properties();
prop.load(...); // FileInputStream 
prop.setProperty("key", "value");
prop.store(...); // FileOutputStream 

MS Access VBA: Sending an email through Outlook

Add a reference to the Outlook object model in the Visual Basic editor. Then you can use the code below to send an email using outlook.

Sub sendOutlookEmail()
Dim oApp As Outlook.Application
Dim oMail As MailItem
Set oApp = CreateObject("Outlook.application")

Set oMail = oApp.CreateItem(olMailItem)
oMail.Body = "Body of the email"
oMail.Subject = "Test Subject"
oMail.To = "[email protected]"
oMail.Send
Set oMail = Nothing
Set oApp = Nothing


End Sub

Excel 2010 VBA - Close file No Save without prompt

If you're not wanting to save changes set savechanges to false

    Sub CloseBook2()
        ActiveWorkbook.Close savechanges:=False
    End Sub

for more examples, http://support.microsoft.com/kb/213428 and i believe in the past I've just used

    ActiveWorkbook.Close False

How to format LocalDate to string?

SimpleDateFormat will not work if he is starting with LocalDate which is new in Java 8. From what I can see, you will have to use DateTimeFormatter, http://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html.

LocalDate localDate = LocalDate.now();//For reference
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd LLLL yyyy");
String formattedString = localDate.format(formatter);

That should print 05 May 1988. To get the period after the day and before the month, you might have to use "dd'.LLLL yyyy"

Lombok annotations do not compile under Intellij idea

If you're using Intellij on Mac, this setup finally worked for me.

Installations: Intellij

  1. Go to Preferences, search for Plugins.
  2. Type "Lombok" in the plugin search box. Lombok is a non-bundled plugin, so it won't show at first.
  3. Click "Browse" to search for non-bundled plugins
  4. The "Lombok Plugin" should show up. Select it.
  5. Click the green "Install" button.
  6. Click the "Restart Intellij IDEA" button.

Settings:

  1. Enable Annotation processor

    • Go to Preferences -> Build, Execution,Deployment -->Preferences -> Compiler -> Annotation Processors
    • File -> Other Settings -> Default Settings -> Compiler -> Annotation Processors
  2. Check if Lombok plugin is enabled

    • IntelliJ IDEA-> Preferences -> Other Settings -> Lombok plugin -> Enable Lombok
  3. Add Lombok jar in Global Libraries and project dependencies.

    • File --> Project Structure --> Global libraries (Add lombok.jar)
  4. File --> Project Structure --> Project Settings --> Modules --> Dependencies Tab = check lombok

  5. Restart Intellij

alert a variable value

If you're using greasemonkey, it's possible the page isn't ready for the javascript yet. You may need to use window.onReady.

var inputs;

function doThisWhenReady() {
    inputs = document.getElementsByTagName('input');

    //Other code here...
}

window.onReady = doThisWhenReady;

difference between primary key and unique key

A primary key’s main features are:

It must contain a unique value for each row of data. It cannot contain null values. Only one Primary key in a table.

A Unique key’s main features are:

It can also contain a unique value for each row of data.

It can also contain null values.

Multiple Unique keys in a table.

How can I check if a string represents an int, without using try/except?

If you're really just annoyed at using try/excepts all over the place, please just write a helper function:

def RepresentsInt(s):
    try: 
        int(s)
        return True
    except ValueError:
        return False

>>> print RepresentsInt("+123")
True
>>> print RepresentsInt("10.0")
False

It's going to be WAY more code to exactly cover all the strings that Python considers integers. I say just be pythonic on this one.

Select all elements with a "data-xxx" attribute without using jQuery

var matches = new Array();

var allDom = document.getElementsByTagName("*");
for(var i =0; i < allDom.length; i++){
    var d = allDom[i];
    if(d["data-foo"] !== undefined) {
         matches.push(d);
    }
}

Not sure who dinged me with a -1, but here's the proof.

http://jsfiddle.net/D798K/2/

What is the javascript filename naming convention?

There is no official, universal, convention for naming JavaScript files.

There are some various options:

  • scriptName.js
  • script-name.js
  • script_name.js

are all valid naming conventions, however I prefer the jQuery suggested naming convention (for jQuery plugins, although it works for any JS)

  • jquery.pluginname.js

The beauty to this naming convention is that it explicitly describes the global namespace pollution being added.

  • foo.js adds window.foo
  • foo.bar.js adds window.foo.bar

Because I left out versioning: it should come after the full name, preferably separated by a hyphen, with periods between major and minor versions:

  • foo-1.2.1.js
  • foo-1.2.2.js
  • ...
  • foo-2.1.24.js

Change a column type from Date to DateTime during ROR migration

Also, if you're using Rails 3 or newer you don't have to use the up and down methods. You can just use change:

class ChangeFormatInMyTable < ActiveRecord::Migration
  def change
    change_column :my_table, :my_column, :my_new_type
  end
end

Difference between JOIN and INNER JOIN

No, there is no difference, pure syntactic sugar.

#pragma once vs include guards?

If you're positive that you will never use this code in a compiler that doesn't support it (Windows/VS, GCC, and Clang are examples of compilers that do support it), then you can certainly use #pragma once without worries.

You can also just use both (see example below), so that you get portability and compilation speedup on compatible systems

#pragma once
#ifndef _HEADER_H_
#define _HEADER_H_

...

#endif

Count the number of occurrences of a character in a string in Javascript

I believe you will find the below solution to be very short, very fast, able to work with very long strings, able to support multiple character searches, error proof, and able to handle empty string searches.

function substring_count(source_str, search_str, index) {
    source_str += "", search_str += "";
    var count = -1, index_inc = Math.max(search_str.length, 1);
    index = (+index || 0) - index_inc;
    do {
        ++count;
        index = source_str.indexOf(search_str, index + index_inc);
    } while (~index);
    return count;
}

Example usage:

_x000D_
_x000D_
console.log(substring_count("Lorem ipsum dolar un sit amet.", "m "))_x000D_
_x000D_
function substring_count(source_str, search_str, index) {_x000D_
    source_str += "", search_str += "";_x000D_
    var count = -1, index_inc = Math.max(search_str.length, 1);_x000D_
    index = (+index || 0) - index_inc;_x000D_
    do {_x000D_
        ++count;_x000D_
        index = source_str.indexOf(search_str, index + index_inc);_x000D_
    } while (~index);_x000D_
    return count;_x000D_
}
_x000D_
_x000D_
_x000D_

The above code fixes the major performance bug in Jakub Wawszczyk's that the code keeps on looks for a match even after indexOf says there is none and his version itself is not working because he forgot to give the function input parameters.

Move top 1000 lines from text file to a new file using Unix shell commands

head -1000 file.txt > first100lines.txt
tail --lines=+1001 file.txt > restoffile.txt

How to deserialize a list using GSON or another JSON library in Java?

Another way is to use an array as a type, e.g.:

Video[] videoArray = gson.fromJson(json, Video[].class);

This way you avoid all the hassle with the Type object, and if you really need a list you can always convert the array to a list, e.g.:

List<Video> videoList = Arrays.asList(videoArray);

IMHO this is much more readable.


In Kotlin this looks like this:

Gson().fromJson(jsonString, Array<Video>::class.java)

To convert this array into List, just use .toList() method

What is the connection string for localdb for version 11

I have connection string Server=(localdb)\v11.0;Integrated Security=true;Database=DB1;

and even a .NET 3.5 program connects and execute SQL successfully.

But many people say .NET 4.0.2 or 4.5 is required.

Is there a way to crack the password on an Excel VBA Project?

Colin Pickard is mostly correct, but don't confuse the "password to open" protection for the entire file with the VBA password protection, which is completely different from the former and is the same for Office 2003 and 2007 (for Office 2007, rename the file to .zip and look for the vbaProject.bin inside the zip). And that technically the correct way to edit the file is to use a OLE compound document viewer like CFX to open up the correct stream. Of course, if you are just replacing bytes, the plain old binary editor may work.

BTW, if you are wondering about the exact format of these fields, they have it documented now:

http://msdn.microsoft.com/en-us/library/dd926151%28v=office.12%29.aspx

Renew Provisioning Profile

Unfortunately renewing does not seem to work in my case. My Ad Hoc Distribution Profile is about to expire in 5 days. I got warnings about that on the iPhone and the Xcode Organizer shows a warning sign next to it as well.

In Apple's provisioning portal it was marked as inactive and there was a button to reactivate it. But still with the same expiry date, 5 days from now. Next, I added two more iPhones to it, yet, the changed profile still expires 5 days from now.

Finally, I deleted the profile in the provisioning portal and created a new one from scratch, using a different name, yet this new one still expires on April 13th, 5 days from now!

That is really frustrating! So I guess I have to wait until after it expires and create a new one then.

In case you are wondering if my developer subscription runs out, it is not. I just renewed it in February.

Call Jquery function

Just add click event by jquery in $(document).ready() like :

$(document).ready(function(){

                  $('#YourControlID').click(function(){
                     if(Check your condtion)
                     {
                             $.messager.show({  
                                title:'My Title',  
                                msg:'The message content',  
                                showType:'fade',  
                                style:{  
                                    right:'',  
                                    bottom:''  
                                }  
                            });  
                     }
                 });
            });

How do you import a large MS SQL .sql file?

I had exactly the same issue and had been struggling for a while then finally found the solution which is to set -a parameter to the sqlcmd in order to change its default packet size:

sqlcmd -S [servername] -d [databasename] -i [scriptfilename] -a 32767

Why do we use $rootScope.$broadcast in AngularJS?

Passing data !!!

I wonder why no one mention that $broadcast accept a parameter where you can pass an Object that will be received by $on using a callback function

Example:

// the object to transfert
var myObject = {
    status : 10
}

$rootScope.$broadcast('status_updated', myObject);
$scope.$on('status_updated', function(event, obj){
    console.log(obj.status); // 10
})

How do I convert an Array to a List<object> in C#?

Use the constructor: new List<object>(myArray)

How can I use Python to get the system hostname?

What about :

import platform

h = platform.uname()[1]

Actually you may want to have a look to all the result in platform.uname()

Change color when hover a font awesome icon?

use - !important - to override default black

_x000D_
_x000D_
.fa-heart:hover{_x000D_
   color:red !important;_x000D_
}_x000D_
.fa-heart-o:hover{_x000D_
   color:red !important;_x000D_
}
_x000D_
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css">_x000D_
_x000D_
<i class="fa fa-heart fa-2x"></i>_x000D_
<i class="fa fa-heart-o fa-2x"></i>
_x000D_
_x000D_
_x000D_

MySQL - How to increase varchar size of an existing column in a database without breaking existing data?

use this syntax: alter table table_name modify column col_name varchar (10000);

How can I change an element's class with JavaScript?

OK, I think in this case you should use jQuery or write your own Methods in pure javascript, my preference is adding my own methods rather than injecting all jQuery to my application if I don't need that for other reasons.

I'd like to do something like below as methods to my javascript framework to add few functionalities which handle adding classes, deleting classes, etc similar to jQuery, this is fully supported in IE9+, also my code is written in ES6, so you need to make sure your browser support it or you using something like babel, otherwise need to use ES5 syntax in your code, also in this way, we finding element via ID, which means the element needs to have an ID to be selected:

//simple javascript utils for class management in ES6
var classUtil = {

  addClass: (id, cl) => {
    document.getElementById(id).classList.add(cl);
  },

  removeClass: (id, cl) => {
    document.getElementById(id).classList.remove(cl);
  },

  hasClass: (id, cl) => {
    return document.getElementById(id).classList.contains(cl);
  },

  toggleClass: (id, cl) => {
    document.getElementById(id).classList.toggle(cl);
  }

}

and you can simply call use them as below, imagine your element has id of 'id' and class of 'class', make sure you pass them as a string, you can use the util as below:

classUtil.addClass('myId', 'myClass');
classUtil.removeClass('myId', 'myClass');
classUtil.hasClass('myId', 'myClass');
classUtil.toggleClass('myId', 'myClass');

git: updates were rejected because the remote contains work that you do not have locally

You can override any checks that git does by using "force push". Use this command in terminal

git push -f origin master

However, you will potentially ignore the existing work that is in remote - you are effectively rewriting the remote's history to be exactly like your local copy.

find . -type f -exec chmod 644 {} ;

A good alternative is this:

find . -type f | xargs chmod -v 644

and for directories:

find . -type d | xargs chmod -v 755

and to be more explicit:

find . -type f | xargs -I{} chmod -v 644 {}

Pull request vs Merge request

GitLab's "merge request" feature is equivalent to GitHub's "pull request" feature. Both are means of pulling changes from another branch or fork into your branch and merging the changes with your existing code. They are useful tools for code review and change management.

An article from GitLab discusses the differences in naming the feature:

Merge or pull requests are created in a git management application and ask an assigned person to merge two branches. Tools such as GitHub and Bitbucket choose the name pull request since the first manual action would be to pull the feature branch. Tools such as GitLab and Gitorious choose the name merge request since that is the final action that is requested of the assignee. In this article we'll refer to them as merge requests.

A "merge request" should not be confused with the git merge command. Neither should a "pull request" be confused with the git pull command. Both git commands are used behind the scenes in both pull requests and merge requests, but a merge/pull request refers to a much broader topic than just these two commands.

How can I turn a List of Lists into a List in Java 8?

flatmap is better but there are other ways to achieve the same

List<List<Object>> listOfList = ... // fill

List<Object> collect = 
      listOfList.stream()
                .collect(ArrayList::new, List::addAll, List::addAll);

Android emulator not able to access the internet

I found a temporary solution on an old Stack Overflow thread at Upgraded to SDK 2.3 - now no emulators have connectivity. Note that this thread talks about Android SDK 2.3, not Android Studio 2.3. The problem seems to be that the emulator can't find the DNS my computer is currently using, and the temporary workaround is to start the emulator from the command line and specify the DNS server. Whatever problem occurred back then must have reappeared in the latest version of Android Studio.

The temporary solution outlined below fixes the problem with the emulator accessing the internet. However, it does not fix the problem that occurs when trying to run Android Device Monitor. Doing so will still make the emulator go offline as described above.

Note that there are two files named "emulator.exe" in the sdk -- one under sdk\tools and another under sdk\emulator. Either might work below, but I use the one under sdk\emulator.

The first step is to find where the SDK is located. Assuming a user name of "jdoe" and a default installation of Android Studio on Windows, the SDK is most likely in

C:\Users\jdoe\AppData\Local\Android\sdk

The second step is to determine the name of the AVD (emulator) that you want to run. The command

C:\Users\jdoe\AppData\Local\Android\sdk\emulator\emulator.exe -list-avds

will show the names of your AVDs. On my computer, it shows only one, Nexus_5X_API_25.

To start the emulator from the command line with a specified DNS server, use something like the following:

C:\Users\jdoe\AppData\Local\Android\sdk\emulator\emulator.exe -avd Nexus_5X_API_25 -dns-server 8.8.8.8

In this case, 8.8.8.8 is a Google public domain name server.

The above commands can be shortened if you create appropriate environment variables and edit your PATH environment variable, but I recommend caution when doing so.

Why is Git better than Subversion?

Easy Git has a nice page comparing actual usage of Git and SVN which will give you an idea of what things Git can do (or do more easily) compared to SVN. (Technically, this is based on Easy Git, which is a lightweight wrapper on top of Git.)

Python: find position of element in array

As Aaron states, you can use .index(value), but because that will throw an exception if value is not present, you should handle that case, even if you're sure it will never happen. A couple options are by checking its presence first, such as:

if value in my_list:
    value_index = my_list.index(value)

or by catching the exception as in:

try:
    value_index = my_list.index(value)
except:
    value_index = -1

You can never go wrong with proper error handling.

PostgreSQL visual interface similar to phpMyAdmin?

I would also highly recommend Adminer - http://www.adminer.org/

It is much faster than phpMyAdmin, does less funky iframe stuff, and supports both MySQL and PostgreSQL.

Difference between Python's Generators and Iterators

Previous answers missed this addition: a generator has a close method, while typical iterators don’t. The close method triggers a StopIteration exception in the generator, which may be caught in a finally clause in that iterator, to get a chance to run some clean-up. This abstraction makes it most usable in the large than simple iterators. One can close a generator as one could close a file, without having to bother about what’s underneath.

That said, my personal answer to the first question would be: iteratable has an __iter__ method only, typical iterators have a __next__ method only, generators has both an __iter__ and a __next__ and an additional close.

For the second question, my personal answer would be: in a public interface, I tend to favor generators a lot, since it’s more resilient: the close method an a greater composability with yield from. Locally, I may use iterators, but only if it’s a flat and simple structure (iterators does not compose easily) and if there are reasons to believe the sequence is rather short especially if it may be stopped before it reach the end. I tend to look at iterators as a low level primitive, except as literals.

For control flow matters, generators are an as much important concept as promises: both are abstract and composable.

How to manually install a pypi module without pip/easy_install?

  1. Download the package
  2. unzip it if it is zipped
  3. cd into the directory containing setup.py
  4. If there are any installation instructions contained in documentation contianed herein, read and follow the instructions OTHERWISE
  5. type in python setup.py install

You may need administrator privileges for step 5. What you do here thus depends on your operating system. For example in Ubuntu you would say sudo python setup.py install

EDIT- thanks to kwatford (see first comment)

To bypass the need for administrator privileges during step 5 above you may be able to make use of the --user flag. In this way you can install the package only for the current user.

The docs say:

Files will be installed into subdirectories of site.USER_BASE (written as userbase hereafter). This scheme installs pure Python modules and extension modules in the same location (also known as site.USER_SITE). Here are the values for UNIX, including Mac OS X:

More details can be found here: http://docs.python.org/2.7/install/index.html

How to check for null in a single statement in scala?

Although I'm sure @Ben Jackson's asnwer with Option(getObject).foreach is the preferred way of doing it, I like to use an AnyRef pimp that allows me to write:

getObject ifNotNull ( QueueManager.add(_) )

I find it reads better.

And, in a more general way, I sometimes write

val returnVal = getObject ifNotNull { obj =>
  returnSomethingFrom(obj)
} otherwise {
  returnSomethingElse
}

... replacing ifNotNull with ifSome if I'm dealing with an Option. I find it clearer than first wrapping in an option and then pattern-matching it.

(For the implementation, see Implementing ifTrue, ifFalse, ifSome, ifNone, etc. in Scala to avoid if(...) and simple pattern matching and the Otherwise0/Otherwise1 classes.)

Compiler error: memset was not declared in this scope

Whevever you get a problem like this just go to the man page for the function in question and it will tell you what header you are missing, e.g.

$ man memset

MEMSET(3)                BSD Library Functions Manual                MEMSET(3)

NAME
     memset -- fill a byte string with a byte value

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <string.h>

     void *
     memset(void *b, int c, size_t len);

Note that for C++ it's generally preferable to use the proper equivalent C++ headers, <cstring>/<cstdio>/<cstdlib>/etc, rather than C's <string.h>/<stdio.h>/<stdlib.h>/etc.

here-document gives 'unexpected end of file' error

When I want to have docstrings for my bash functions, I use a solution similar to the suggestion of user12205 in a duplicate of this question.

See how I define USAGE for a solution that:

  • auto-formats well for me in my IDE of choice (sublime)
  • is multi-line
  • can use spaces or tabs as indentation
  • preserves indentations within the comment.
function foo {
    # Docstring
    read -r -d '' USAGE <<'    END'
        # This method prints foo to the terminal.
        #
        # Enter `foo -h` to see the docstring.
        #      It has indentations and multiple lines.
        #
        # Change the delimiter if you need hashtag for some reason.
        # This can include $$ and = and eval, but won't be evaluated
    END


    if [ "$1" = "-h" ]
    then
        echo "$USAGE" | cut -d "#" -f 2 | cut -c 2-
        return
    fi

    echo "foo"
}

So foo -h yields:

This method prints foo to the terminal.

Enter `foo -h` to see the docstring.
     It has indentations and multiple lines.

Change the delimiter if you need hashtag for some reason.
This can include $$ and = and eval, but won't be evaluated

Explanation

cut -d "#" -f 2: Retrieve the second portion of the # delimited lines. (Think a csv with "#" as the delimiter, empty first column).

cut -c 2-: Retrieve the 2nd to end character of the resultant string

Also note that if [ "$1" = "-h" ] evaluates as False if there is no first argument, w/o error, since it becomes an empty string.

Getting list of Facebook friends with latest API

in the recent version of facebook sdk , facebook has disabled the feature that let you access some one friends list due to security reasons ... check the documentation to learn more ...

How does createOrReplaceTempView work in Spark?

CreateOrReplaceTempView will create a temporary view of the table on memory it is not presistant at this moment but you can run sql query on top of that . if you want to save it you can either persist or use saveAsTable to save.

first we read data in csv format and then convert to data frame and create a temp view

Reading data in csv format

val data = spark.read.format("csv").option("header","true").option("inferSchema","true").load("FileStore/tables/pzufk5ib1500654887654/campaign.csv")

printing the schema

data.printSchema

SchemaOfTable

data.createOrReplaceTempView("Data")

Now we can run sql queries on top the table view we just created

  %sql select Week as Date,Campaign Type,Engagements,Country from Data order     by Date asc

enter image description here

How to convert string to integer in UNIX

An answer that is not limited to the OP's case

The title of the question leads people here, so I decided to answer that question for everyone else since the OP's described case was so limited.

TL;DR

I finally settled on writing a function.

  1. If you want 0 in case of non-int:
int(){ printf '%d' ${1:-} 2>/dev/null || :; }
  1. If you want [empty_string] in case of non-int:
int(){ expr 0 + ${1:-} 2>/dev/null||:; }
  1. If you want find the first int or [empty_string]:
int(){ expr ${1:-} : '[^0-9]*\([0-9]*\)' 2>/dev/null||:; }
  1. If you want find the first int or 0:
# This is a combination of numbers 1 and 2
int(){ expr ${1:-} : '[^0-9]*\([0-9]*\)' 2>/dev/null||:; }

If you want to get a non-zero status code on non-int, remove the ||: (aka or true) but leave the ;

Tests

# Wrapped in parens to call a subprocess and not `set` options in the main bash process
# In other words, you can literally copy-paste this code block into your shell to test
( set -eu;
    tests=( 4 "5" "6foo" "bar7" "foo8.9bar" "baz" " " "" )
    test(){ echo; type int; for test in "${tests[@]}"; do echo "got '$(int $test)' from '$test'"; done; echo "got '$(int)' with no argument"; }

    int(){ printf '%d' ${1:-} 2>/dev/null||:; };
    test

    int(){ expr 0 + ${1:-} 2>/dev/null||:; }
    test

    int(){ expr ${1:-} : '[^0-9]*\([0-9]*\)' 2>/dev/null||:; }
    test

    int(){ printf '%d' $(expr ${1:-} : '[^0-9]*\([0-9]*\)' 2>/dev/null)||:; }
    test

    # unexpected inconsistent results from `bc`
    int(){ bc<<<"${1:-}" 2>/dev/null||:; }
    test
)

Test output

int is a function
int ()
{
    printf '%d' ${1:-} 2> /dev/null || :
}
got '4' from '4'
got '5' from '5'
got '0' from '6foo'
got '0' from 'bar7'
got '0' from 'foo8.9bar'
got '0' from 'baz'
got '0' from ' '
got '0' from ''
got '0' with no argument

int is a function
int ()
{
    expr 0 + ${1:-} 2> /dev/null || :
}
got '4' from '4'
got '5' from '5'
got '' from '6foo'
got '' from 'bar7'
got '' from 'foo8.9bar'
got '' from 'baz'
got '' from ' '
got '' from ''
got '' with no argument

int is a function
int ()
{
    expr ${1:-} : '[^0-9]*\([0-9]*\)' 2> /dev/null || :
}
got '4' from '4'
got '5' from '5'
got '6' from '6foo'
got '7' from 'bar7'
got '8' from 'foo8.9bar'
got '' from 'baz'
got '' from ' '
got '' from ''
got '' with no argument

int is a function
int ()
{
    printf '%d' $(expr ${1:-} : '[^0-9]*\([0-9]*\)' 2>/dev/null) || :
}
got '4' from '4'
got '5' from '5'
got '6' from '6foo'
got '7' from 'bar7'
got '8' from 'foo8.9bar'
got '0' from 'baz'
got '0' from ' '
got '0' from ''
got '0' with no argument

int is a function
int ()
{
    bc <<< "${1:-}" 2> /dev/null || :
}
got '4' from '4'
got '5' from '5'
got '' from '6foo'
got '0' from 'bar7'
got '' from 'foo8.9bar'
got '0' from 'baz'
got '' from ' '
got '' from ''
got '' with no argument

Note

I got sent down this rabbit hole because the accepted answer is not compatible with set -o nounset (aka set -u)

# This works
$ ( number="3"; string="foo"; echo $((number)) $((string)); )
3 0

# This doesn't
$ ( set -u; number="3"; string="foo"; echo $((number)) $((string)); )
-bash: foo: unbound variable

How can I create tests in Android Studio?

I think this post by Rex St John is very useful for unit testing with android studio.


(source: rexstjohn.com)

java.security.cert.CertificateException: Certificates does not conform to algorithm constraints

colleagues.

I have faced with this trouble during a development of automation tests for our REST API. JDK 7_80 was installed at my machine only. Before I installed JDK 8, everything worked just fine and I had a possibility to obtain OAuth 2.0 tokens with a JMeter. After I installed JDK 8, the nightmare with Certificates does not conform to algorithm constraints began.

Both JMeter and Serenity did not have a possibility to obtain a token. JMeter uses the JDK library to make the request. The library just raises an exception when the library call is made to connect to endpoints that use it, ignoring the request.

The next thing was to comment all the lines dedicated to disabledAlgorithms in ALL java.security files.

C:\Java\jre7\lib\security\java.security
C:\Java\jre8\lib\security\java.security
C:\Java\jdk8\jre\lib\security\java.security
C:\Java\jdk7\jre\lib\security\java.security

Then it started to work at last. I know, that's a brute force approach, but it was the most simple way to fix it.

# jdk.tls.disabledAlgorithms=SSLv3, RC4, MD5withRSA, DH keySize < 768
# jdk.certpath.disabledAlgorithms=MD2, MD5, RSA keySize < 1024

Getting the value of an attribute in XML

This is more of an xpath question, but like this, assuming the context is the parent element:

<xsl:value-of select="name/@attribute1" />

Compare objects in Angular

Assuming that the order is the same in both objects, just stringify them both and compare!

JSON.stringify(obj1) == JSON.stringify(obj2);

Gradle finds wrong JAVA_HOME even though it's correctly set

In my dockercontainer (being minimal the problem of not finding java) was, that "which" was not installed. Comipling a project using gradlew used which in ./gradlew to find java Installing which solved the problem.

Issue with Task Scheduler launching a task

Thanks all, I had the same issue. I have a task that runs via a generic user account not linked to a particular person. This user as somehow logged off the VM, when I was trying to fix it I was logged in as me and not that user.

Logging back in with that user fixed the issue!

jquery append div inside div with id and manipulate

You're overcomplicating things:

var e = $('<div style="display:block; float:left;width:'+width+'px; height:'+height+'px; margin-top:'+positionY+'px;margin-left:'+positionX+'px;border:1px dashed #CCCCCC;"></div>');
e.attr('id', 'myid');
$('#box').append(e);

For example: http://jsfiddle.net/ambiguous/Dm5J2/

Insert string at specified position

Strange answers here! You can insert strings into other strings easily with sprintf [link to documentation]. The function is extremely powerful and can handle multiple elements and other data types too.

$color = 'green';
sprintf('I like %s apples.', $color);

gives you the string

I like green apples.

What's the difference between an element and a node in XML?

A node is the base class for both elements and attributes (and basically all other XML representations too).

Can I set background image and opacity in the same property?

Well the only CSS way of doing only background transparency is via RGBa but since you want to use an image I would suggest using Photoshop or Gimp to make the image transparent and then using it as the background.

How to use a variable for the database name in T-SQL?

Put the entire script into a template string, with {SERVERNAME} placeholders. Then edit the string using:

SET @SQL_SCRIPT = REPLACE(@TEMPLATE, '{SERVERNAME}', @DBNAME)

and then run it with

EXECUTE (@SQL_SCRIPT)

It's hard to believe that, in the course of three years, nobody noticed that my code doesn't work!

You can't EXEC multiple batches. GO is a batch separator, not a T-SQL statement. It's necessary to build three separate strings, and then to EXEC each one after substitution.

I suppose one could do something "clever" by breaking the single template string into multiple rows by splitting on GO; I've done that in ADO.NET code.

And where did I get the word "SERVERNAME" from?

Here's some code that I just tested (and which works):

DECLARE @DBNAME VARCHAR(255)
SET @DBNAME = 'TestDB'

DECLARE @CREATE_TEMPLATE VARCHAR(MAX)
DECLARE @COMPAT_TEMPLATE VARCHAR(MAX)
DECLARE @RECOVERY_TEMPLATE VARCHAR(MAX)

SET @CREATE_TEMPLATE = 'CREATE DATABASE {DBNAME}'
SET @COMPAT_TEMPLATE='ALTER DATABASE {DBNAME} SET COMPATIBILITY_LEVEL = 90'
SET @RECOVERY_TEMPLATE='ALTER DATABASE {DBNAME} SET RECOVERY SIMPLE'

DECLARE @SQL_SCRIPT VARCHAR(MAX)

SET @SQL_SCRIPT = REPLACE(@CREATE_TEMPLATE, '{DBNAME}', @DBNAME)
EXECUTE (@SQL_SCRIPT)

SET @SQL_SCRIPT = REPLACE(@COMPAT_TEMPLATE, '{DBNAME}', @DBNAME)
EXECUTE (@SQL_SCRIPT)

SET @SQL_SCRIPT = REPLACE(@RECOVERY_TEMPLATE, '{DBNAME}', @DBNAME)
EXECUTE (@SQL_SCRIPT)

Create a new Ruby on Rails application using MySQL instead of SQLite

If you already have a rails project, change the adapter in the config/database.yml file to mysql and make sure you specify a valid username and password, and optionally, a socket:

development:
  adapter: mysql2
  database: db_name_dev
  username: koploper
  password:
  host: localhost
  socket: /tmp/mysql.sock

Next, make sure you edit your Gemfile to include the mysql2 or activerecord-jdbcmysql-adapter (if using jruby).

How to center a (background) image within a div?

This works for me:

#doit{
    background-image: url('images/pic.png');
    background-repeat: no-repeat;
    background-position: center;  
}  

Regular expression to search multiple strings (Textpad)

To get the lines that contain the texts 8768, 9875 or 2353, use:

^.*(8768|9875|2353).*$

What it means:

^                      from the beginning of the line
.*                     get any character except \n (0 or more times)
(8768|9875|2353)       if the line contains the string '8768' OR '9875' OR '2353'
.*                     and get any character except \n (0 or more times)
$                      until the end of the line

If you do want the literal * char, you'd have to escape it:

^.*(\*8768|\*9875|\*2353).*$

wait() or sleep() function in jquery?

There is an function, but it's extra: http://docs.jquery.com/Cookbook/wait

This little snippet allows you to wait:

$.fn.wait = function(time, type) {
    time = time || 1000;
    type = type || "fx";
    return this.queue(type, function() {
        var self = this;
        setTimeout(function() {
            $(self).dequeue();
        }, time);
    });
};

how to instanceof List<MyType>?

You probably need to use reflection to get the types of them to check. To get the type of the List: Get generic type of java.util.List

How to view an HTML file in the browser with Visual Studio Code

CTRL+SHIFT+P will bring up the command palette.
Depending on what you're running of course. Example in an ASP.net app you can type in:
>kestrel and then open up your web browser and type in localhost:(your port here).

If you type in > it will show you the show and run commands

Or in your case with HTML, I think F5 after opening the command palette should open the debugger.

Source: link

LEFT INNER JOIN vs. LEFT OUTER JOIN - Why does the OUTER take longer?

This is because the LEFT OUTER Join is doing more work than an INNER Join BEFORE sending the results back.

The Inner Join looks for all records where the ON statement is true (So when it creates a new table, it only puts in records that match the m.SubID = a.SubID). Then it compares those results to your WHERE statement (Your last modified time).

The Left Outer Join...Takes all of the records in your first table. If the ON statement is not true (m.SubID does not equal a.SubID), it simply NULLS the values in the second table's column for that recordset.

The reason you get the same number of results at the end is probably coincidence due to the WHERE clause that happens AFTER all of the copying of records.

Join (SQL) Wikipedia

Send POST data using XMLHttpRequest

NO PLUGINS NEEDED!

Select the below code and drag that into in BOOKMARK BAR (if you don't see it, enable from Browser Settings), then EDIT that link :

enter image description here

javascript:var my_params = prompt("Enter your parameters", "var1=aaaa&var2=bbbbb"); var Target_LINK = prompt("Enter destination", location.href); function post(path, params) { var xForm = document.createElement("form"); xForm.setAttribute("method", "post"); xForm.setAttribute("action", path); for (var key in params) { if (params.hasOwnProperty(key)) { var hiddenField = document.createElement("input"); hiddenField.setAttribute("name", key); hiddenField.setAttribute("value", params[key]); xForm.appendChild(hiddenField); } } var xhr = new XMLHttpRequest(); xhr.onload = function () { alert(xhr.responseText); }; xhr.open(xForm.method, xForm.action, true); xhr.send(new FormData(xForm)); return false; } parsed_params = {}; my_params.split("&").forEach(function (item) { var s = item.split("="), k = s[0], v = s[1]; parsed_params[k] = v; }); post(Target_LINK, parsed_params); void(0);

That's all! Now you can visit any website, and click that button in BOOKMARK BAR!


NOTE:

The above method sends data using XMLHttpRequest method, so, you have to be on the same domain while triggering the script. That's why I prefer sending data with a simulated FORM SUBMITTING, which can send the code to any domain - here is code for that:

 javascript:var my_params=prompt("Enter your parameters","var1=aaaa&var2=bbbbb"); var Target_LINK=prompt("Enter destination", location.href); function post(path, params) {   var xForm= document.createElement("form");   xForm.setAttribute("method", "post");   xForm.setAttribute("action", path); xForm.setAttribute("target", "_blank");   for(var key in params) {   if(params.hasOwnProperty(key)) {        var hiddenField = document.createElement("input");      hiddenField.setAttribute("name", key);      hiddenField.setAttribute("value", params[key]);         xForm.appendChild(hiddenField);     }   }   document.body.appendChild(xForm);  xForm.submit(); }   parsed_params={}; my_params.split("&").forEach(function(item) {var s = item.split("="), k=s[0], v=s[1]; parsed_params[k] = v;}); post(Target_LINK, parsed_params); void(0); 

How can you zip or unzip from the script using ONLY Windows' built-in capabilities?

If you need to do this as part of a script then the best way is to use Java. Assuming the bin directory is in your path (in most cases), you can use the command line:

jar xf test.zip

If Java is not on your path, reference it directly:

C:\Java\jdk1.6.0_03\bin>jar xf test.zip

How to sort an array of integers correctly

Array.prototype.sort() is the go to method for sorting arrays, but there are a couple of issues we need to be aware of.

The sorting order is by default lexicographic and not numeric regardless of the types of values in the array. Even if the array is all numbers, all values will be converted to string and sorted lexicographically.

So should we need to customize the sort() and reverse() method like below.

Referred URL

For sorting numbers inside the array

numArray.sort(function(a, b)
{
    return a - b;
});

For reversing numbers inside the array

numArray.sort(function(a, b)
{
    return b - a;
});

Referred URL

Unable to create requested service [org.hibernate.engine.jdbc.env.spi.JdbcEnvironment]

Either you experienced database connection issue or you missed any of the hibernate configurations to connect to database such as database DIALECT.

Happens if your database server was disconnected due to network related issue.

If you're using spring boot along with hibernate connected to Oracle Db, use

hibernate.dialect=org.hibernate.dialect.HSQLDialect
hibernate.show_sql=true
hibernate.hbm2ddl.auto=update
hibernate.generate_statistics=true
entitymanager.packagesToScan: com

Looping through rows in a DataView

You can iterate DefaultView as the following code by Indexer:

DataTable dt = new DataTable();
// add some rows to your table
// ...
dt.DefaultView.Sort = "OneColumnName ASC"; // For example
for (int i = 0; i < dt.Rows.Count; i++)
{
    DataRow oRow = dt.DefaultView[i].Row;
    // Do your stuff with oRow
    // ...
}

python 2 instead of python 3 as the (temporary) default python?

Use python command to launch scripts, not shell directly. E.g.

  python2 /usr/bin/command

AFAIK this is the recommended method to workaround scripts with bad env interpreter line.

How to extract 1 screenshot for a video with ffmpeg at a given time?

FFMpeg can do this by seeking to the given timestamp and extracting exactly one frame as an image, see for instance:

ffmpeg -i input_file.mp4 -ss 01:23:45 -vframes 1 output.jpg

Let's explain the options:

-i input file           the path to the input file
-ss 01:23:45            seek the position to the specified timestamp
-vframes 1              only handle one video frame
output.jpg              output filename, should have a well-known extension

The -ss parameter accepts a value in the form HH:MM:SS[.xxx] or as a number in seconds. If you need a percentage, you need to compute the video duration beforehand.

using if else with eval in aspx page

 <%if (System.Configuration.ConfigurationManager.AppSettings["OperationalMode"] != "live") {%>
                        &nbsp;[<%=System.Environment.MachineName%>]
                        <%}%>

add a temporary column with a value

I giving you an example in wich the TABLE registrofaena doesn't have the column called minutos. Minutos is created and it content is a result of divide demora/60, in other words, i created a column to show the values of the delay in minutes.

This is the query:

SELECT idfaena,fechahora,demora, demora/60 as minutos,comentario 
FROM registrofaena  
WHERE fecha>='2018-10-17' AND comentario <> '' 
ORDER BY idfaena ASC;

This is the view:

This is the result

Maven error :Perhaps you are running on a JRE rather than a JDK?

In Installed JREs path see if there is an entry pointing to your JDK path or not. If not, click on Edit button and put the path you configured your JAVA_HOME environment:

Eclipse Path: Window ? Preferences ? Java ? Installed JREs

Static variables in JavaScript

In addition to the rest, there's currently a draft (stage-2 proposal) on ECMA Proposals that introduces static public fields in classes. (private fields were considered)

Using the example from the proposal, the proposed static syntax will look like this:

class CustomDate {
  // ...
  static epoch = new CustomDate(0);
}

and be equivalent to the following which others have highlighted:

class CustomDate {
  // ...
}
CustomDate.epoch = new CustomDate(0);

You can then access it via CustomDate.epoch.

You can keep track of the new proposal in proposal-static-class-features.


Currently, babel supports this feature with the transform class properties plugin which you can use. Additionally, though still in progress, V8 is implementing it.

How do I delete an exported environment variable?

Walkthrough of creating and deleting an environment variable in bash:

Test if the DUALCASE variable exists:

el@apollo:~$ env | grep DUALCASE
el@apollo:~$ 

It does not, so create the variable and export it:

el@apollo:~$ DUALCASE=1
el@apollo:~$ export DUALCASE

Check if it is there:

el@apollo:~$ env | grep DUALCASE
DUALCASE=1

It is there. So get rid of it:

el@apollo:~$ unset DUALCASE

Check if it's still there:

el@apollo:~$ env | grep DUALCASE
el@apollo:~$ 

The DUALCASE exported environment variable is deleted.

Extra commands to help clear your local and environment variables:

Unset all local variables back to default on login:

el@apollo:~$ CAN="chuck norris"
el@apollo:~$ set | grep CAN
CAN='chuck norris'
el@apollo:~$ env | grep CAN
el@apollo:~$
el@apollo:~$ exec bash
el@apollo:~$ set | grep CAN
el@apollo:~$ env | grep CAN
el@apollo:~$

exec bash command cleared all the local variables but not environment variables.

Unset all environment variables back to default on login:

el@apollo:~$ export DOGE="so wow"
el@apollo:~$ env | grep DOGE
DOGE=so wow
el@apollo:~$ env -i bash
el@apollo:~$ env | grep DOGE
el@apollo:~$

env -i bash command cleared all the environment variables to default on login.

Setting query string using Fetch GET request

let params = {
  "param1": "value1",
  "param2": "value2"
};

let query = Object.keys(params)
             .map(k => encodeURIComponent(k) + '=' + encodeURIComponent(params[k]))
             .join('&');

let url = 'https://example.com/search?' + query;

fetch(url)
  .then(data => data.text())
  .then((text) => {
    console.log('request succeeded with JSON response', text)
  }).catch(function (error) {
    console.log('request failed', error)
  });

Confirm deletion using Bootstrap 3 modal box

<!-- Button trigger modal -->
<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#exampleModal">
  Launch demo modal
</button>

<!-- Modal -->
<div class="modal fade" id="exampleModal" tabindex="-1" role="dialog" aria-labelledby="exampleModalLabel" aria-hidden="true">
  <div class="modal-dialog" role="document">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title" id="exampleModalLabel">Modal title</h5>
        <button type="button" class="close" data-dismiss="modal" aria-label="Close">
          <span aria-hidden="true">&times;</span>
        </button>
      </div>
      <div class="modal-body">
        ...
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>

https://getbootstrap.com/docs/4.0/components/modal/

jQuery Datepicker localization

You can do like this

 $.datepicker.regional['fr'] = {clearText: 'Effacer', clearStatus: '',
    closeText: 'Fermer', closeStatus: 'Fermer sans modifier',
    prevText: '&lt;Préc', prevStatus: 'Voir le mois précédent',
    nextText: 'Suiv&gt;', nextStatus: 'Voir le mois suivant',
    currentText: 'Courant', currentStatus: 'Voir le mois courant',
    monthNames: ['Janvier','Février','Mars','Avril','Mai','Juin',
    'Juillet','Août','Septembre','Octobre','Novembre','Décembre'],
    monthNamesShort: ['Jan','Fév','Mar','Avr','Mai','Jun',
    'Jul','Aoû','Sep','Oct','Nov','Déc'],
    monthStatus: 'Voir un autre mois', yearStatus: 'Voir un autre année',
    weekHeader: 'Sm', weekStatus: '',
    dayNames: ['Dimanche','Lundi','Mardi','Mercredi','Jeudi','Vendredi','Samedi'],
    dayNamesShort: ['Dim','Lun','Mar','Mer','Jeu','Ven','Sam'],
    dayNamesMin: ['Di','Lu','Ma','Me','Je','Ve','Sa'],
    dayStatus: 'Utiliser DD comme premier jour de la semaine', dateStatus: 'Choisir le DD, MM d',
    dateFormat: 'dd/mm/yy', firstDay: 0, 
    initStatus: 'Choisir la date', isRTL: false};
 $.datepicker.setDefaults($.datepicker.regional['fr']);

How to Retrieve value from JTextField in Java Swing?

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Swingtest extends JFrame implements ActionListener
{
    JTextField txtdata;
    JButton calbtn = new JButton("Calculate");

    public Swingtest()
    {
        JPanel myPanel = new JPanel();
        add(myPanel);
        myPanel.setLayout(new GridLayout(3, 2));
        myPanel.add(calbtn);
        calbtn.addActionListener(this);
        txtdata = new JTextField();
        myPanel.add(txtdata);
    }

    public void actionPerformed(ActionEvent e)
    {
        if (e.getSource() == calbtn) {
            String data = txtdata.getText(); //perform your operation
            System.out.println(data);
        }
    }

    public static void main(String args[])
    {
        Swingtest g = new Swingtest();
        g.setLocation(10, 10);
        g.setSize(300, 300);
        g.setVisible(true);
    }
}

now its working

Curly braces in string in PHP

This is the complex (curly) syntax for string interpolation. From the manual:

Complex (curly) syntax

This isn't called complex because the syntax is complex, but because it allows for the use of complex expressions.

Any scalar variable, array element or object property with a string representation can be included via this syntax. Simply write the expression the same way as it would appear outside the string, and then wrap it in { and }. Since { can not be escaped, this syntax will only be recognised when the $ immediately follows the {. Use {\$ to get a literal {$. Some examples to make it clear:

<?php
// Show all errors
error_reporting(E_ALL);

$great = 'fantastic';

// Won't work, outputs: This is { fantastic}
echo "This is { $great}";

// Works, outputs: This is fantastic
echo "This is {$great}";
echo "This is ${great}";

// Works
echo "This square is {$square->width}00 centimeters broad."; 


// Works, quoted keys only work using the curly brace syntax
echo "This works: {$arr['key']}";


// Works
echo "This works: {$arr[4][3]}";

// This is wrong for the same reason as $foo[bar] is wrong  outside a string.
// In other words, it will still work, but only because PHP first looks for a
// constant named foo; an error of level E_NOTICE (undefined constant) will be
// thrown.
echo "This is wrong: {$arr[foo][3]}"; 

// Works. When using multi-dimensional arrays, always use braces around arrays
// when inside of strings
echo "This works: {$arr['foo'][3]}";

// Works.
echo "This works: " . $arr['foo'][3];

echo "This works too: {$obj->values[3]->name}";

echo "This is the value of the var named $name: {${$name}}";

echo "This is the value of the var named by the return value of getName(): {${getName()}}";

echo "This is the value of the var named by the return value of \$object->getName(): {${$object->getName()}}";

// Won't work, outputs: This is the return value of getName(): {getName()}
echo "This is the return value of getName(): {getName()}";
?>

Often, this syntax is unnecessary. For example, this:

$a = 'abcd';
$out = "$a $a"; // "abcd abcd";

behaves exactly the same as this:

$out = "{$a} {$a}"; // same

So the curly braces are unnecessary. But this:

$out = "$aefgh";

will, depending on your error level, either not work or produce an error because there's no variable named $aefgh, so you need to do:

$out = "${a}efgh"; // or
$out = "{$a}efgh";

How to merge a transparent png image with another image using PIL

Image.paste does not work as expected when the background image also contains transparency. You need to use real Alpha Compositing.

Pillow 2.0 contains an alpha_composite function that does this.

background = Image.open("test1.png")
foreground = Image.open("test2.png")

Image.alpha_composite(background, foreground).save("test3.png")

EDIT: Both images need to be of the type RGBA. So you need to call convert('RGBA') if they are paletted, etc.. If the background does not have an alpha channel, then you can use the regular paste method (which should be faster).

Making view resize to its parent when added with addSubview

If you aren’t using Auto Layout, have you tried setting the child view’s autoresize mask? Try this:

myChildeView.autoresizingMask = (UIViewAutoresizingFlexibleWidth |
                                 UIViewAutoresizingFlexibleHeight);

Also, you may need to call

myParentView.autoresizesSubviews = YES;

to get the parent view to resize its subviews automatically when its frame changes.

If you’re still seeing the child view drawing outside of the parent view’s frame, there’s a good chance that the parent view is not clipping its contents. To fix that, call

myParentView.clipsToBounds = YES;

Array formula on Excel for Mac


Select the range, press CONTROL+U and then press ?+RETURN.


Make scrollbars only visible when a Div is hovered over?

Answer by @Calvin Froedge is the shortest answer but have an issue also mentioned by @kizu. Due to inconsistent width of the div the div will flick on hover. To solve this issue add minus margin to the right on hover

#div { 
     overflow:hidden;
     height:whatever px; 
}
#div:hover { 
     overflow-y:scroll; 
     margin-right: -15px; // adjust according to scrollbar width  
}

Can't update data-attribute value

For myself, using Jquery lib 2.1.1 the following did NOT work the way I expected:

Set element data attribute value:

$('.my-class').data('num', 'myValue');
console.log($('#myElem').data('num'));// as expected = 'myValue'

BUT the element itself remains without the attribute:

<div class="my-class"></div>

I needed the DOM updated so I could later do $('.my-class[data-num="myValue"]') //current length is 0

So I had to do

$('.my-class').attr('data-num', 'myValue');

To get the DOM to update:

<div class="my-class" data-num="myValue"></div>

Whether the attribute exists or not $.attr will overwrite.

How to install cron

Installing Crontab on Ubuntu

sudo apt-get update

We download the crontab file to the root

wget https://pypi.python.org/packages/47/c2/d048cbe358acd693b3ee4b330f79d836fb33b716bfaf888f764ee60aee65/crontab-0.20.tar.gz

Unzip the file crontab-0.20.tar.gz

tar xvfz crontab-0.20.tar.gz

Login to a folder crontab-0.20

cd crontab-0.20*

Installation order

python setup.py install

See also here:.. http://www.syriatalk.im/crontab.html

Export pictures from excel file into jpg using VBA

''' Set Range you want to export to the folder

Workbooks("your workbook name").Sheets("yoursheet name").Select

Dim rgExp As Range: Set rgExp = Range("A1:H31")
''' Copy range as picture onto Clipboard
rgExp.CopyPicture Appearance:=xlScreen, Format:=xlBitmap
''' Create an empty chart with exact size of range copied
With ActiveSheet.ChartObjects.Add(Left:=rgExp.Left, Top:=rgExp.Top, _
Width:=rgExp.Width, Height:=rgExp.Height)
.Name = "ChartVolumeMetricsDevEXPORT"
.Activate
End With
''' Paste into chart area, export to file, delete chart.
ActiveChart.Paste
ActiveSheet.ChartObjects("ChartVolumeMetricsDevEXPORT").Chart.Export "C:\ExportmyChart.jpg"
ActiveSheet.ChartObjects("ChartVolumeMetricsDevEXPORT").Delete

Retain precision with double in Java

As others have mentioned, you'll probably want to use the BigDecimal class, if you want to have an exact representation of 11.4.

Now, a little explanation into why this is happening:

The float and double primitive types in Java are floating point numbers, where the number is stored as a binary representation of a fraction and a exponent.

More specifically, a double-precision floating point value such as the double type is a 64-bit value, where:

  • 1 bit denotes the sign (positive or negative).
  • 11 bits for the exponent.
  • 52 bits for the significant digits (the fractional part as a binary).

These parts are combined to produce a double representation of a value.

(Source: Wikipedia: Double precision)

For a detailed description of how floating point values are handled in Java, see the Section 4.2.3: Floating-Point Types, Formats, and Values of the Java Language Specification.

The byte, char, int, long types are fixed-point numbers, which are exact representions of numbers. Unlike fixed point numbers, floating point numbers will some times (safe to assume "most of the time") not be able to return an exact representation of a number. This is the reason why you end up with 11.399999999999 as the result of 5.6 + 5.8.

When requiring a value that is exact, such as 1.5 or 150.1005, you'll want to use one of the fixed-point types, which will be able to represent the number exactly.

As has been mentioned several times already, Java has a BigDecimal class which will handle very large numbers and very small numbers.

From the Java API Reference for the BigDecimal class:

Immutable, arbitrary-precision signed decimal numbers. A BigDecimal consists of an arbitrary precision integer unscaled value and a 32-bit integer scale. If zero or positive, the scale is the number of digits to the right of the decimal point. If negative, the unscaled value of the number is multiplied by ten to the power of the negation of the scale. The value of the number represented by the BigDecimal is therefore (unscaledValue × 10^-scale).

There has been many questions on Stack Overflow relating to the matter of floating point numbers and its precision. Here is a list of related questions that may be of interest:

If you really want to get down to the nitty gritty details of floating point numbers, take a look at What Every Computer Scientist Should Know About Floating-Point Arithmetic.

How to fix Git error: object file is empty?

I fixed my git error: object file is empty by:

  1. Saving a copy of all files that I edited since my last successful commit/push,
  2. Removing and re-cloning my repository,
  3. Replacing the old files with my edited files.

Hopes this helps.

Create a dropdown component

This is the code to create dropdown in Angular 7, 8, 9

.html file code

<div>
<label>Summary: </label>
<select (change)="SelectItem($event.target.value)" class="select">
  <option value="0">--All--</option>
  <option *ngFor="let item of items" value="{{item.Id.Value}}">
    {{item.Name}}
  </option>
</select>
</div>

.ts file code

SelectItem(filterVal: any)
{
    var id=filterVal;
    //code
}

items is an array which should be initialized in .ts file.

Catch multiple exceptions at once?

Update 2015-12-15: See https://stackoverflow.com/a/22864936/1718702 for C#6. It's a cleaner and now standard in the language.

Geared for people that want a more elegant solution to catch once and filter exceptions, I use an extension method as demonstrated below.

I already had this extension in my library, originally written for other purposes, but it worked just perfectly for type checking on exceptions. Plus, imho, it looks cleaner than a bunch of || statements. Also, unlike the accepted answer, I prefer explicit exception handling so ex is ... had undesireable behaviour as derrived classes are assignable to there parent types).

Usage

if (ex.GetType().IsAnyOf(
    typeof(FormatException),
    typeof(ArgumentException)))
{
    // Handle
}
else
    throw;

IsAnyOf.cs Extension (See Full Error Handling Example for Dependancies)

namespace Common.FluentValidation
{
    public static partial class Validate
    {
        /// <summary>
        /// Validates the passed in parameter matches at least one of the passed in comparisons.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="p_parameter">Parameter to validate.</param>
        /// <param name="p_comparisons">Values to compare against.</param>
        /// <returns>True if a match is found.</returns>
        /// <exception cref="ArgumentNullException"></exception>
        public static bool IsAnyOf<T>(this T p_parameter, params T[] p_comparisons)
        {
            // Validate
            p_parameter
                .CannotBeNull("p_parameter");
            p_comparisons
                .CannotBeNullOrEmpty("p_comparisons");

            // Test for any match
            foreach (var item in p_comparisons)
                if (p_parameter.Equals(item))
                    return true;

            // Return no matches found
            return false;
        }
    }
}

Full Error Handling Example (Copy-Paste to new Console app)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Common.FluentValidation;

namespace IsAnyOfExceptionHandlerSample
{
    class Program
    {
        static void Main(string[] args)
        {
            // High Level Error Handler (Log and Crash App)
            try
            {
                Foo();
            }
            catch (OutOfMemoryException ex)
            {
                Console.WriteLine("FATAL ERROR! System Crashing. " + ex.Message);
                Console.ReadKey();
            }
        }

        static void Foo()
        {
            // Init
            List<Action<string>> TestActions = new List<Action<string>>()
            {
                (key) => { throw new FormatException(); },
                (key) => { throw new ArgumentException(); },
                (key) => { throw new KeyNotFoundException();},
                (key) => { throw new OutOfMemoryException(); },
            };

            // Run
            foreach (var FooAction in TestActions)
            {
                // Mid-Level Error Handler (Appends Data for Log)
                try
                {
                    // Init
                    var SomeKeyPassedToFoo = "FooParam";

                    // Low-Level Handler (Handle/Log and Keep going)
                    try
                    {
                        FooAction(SomeKeyPassedToFoo);
                    }
                    catch (Exception ex)
                    {
                        if (ex.GetType().IsAnyOf(
                            typeof(FormatException),
                            typeof(ArgumentException)))
                        {
                            // Handle
                            Console.WriteLine("ex was {0}", ex.GetType().Name);
                            Console.ReadKey();
                        }
                        else
                        {
                            // Add some Debug info
                            ex.Data.Add("SomeKeyPassedToFoo", SomeKeyPassedToFoo.ToString());
                            throw;
                        }
                    }
                }
                catch (KeyNotFoundException ex)
                {
                    // Handle differently
                    Console.WriteLine(ex.Message);

                    int Count = 0;
                    if (!Validate.IsAnyNull(ex, ex.Data, ex.Data.Keys))
                        foreach (var Key in ex.Data.Keys)
                            Console.WriteLine(
                                "[{0}][\"{1}\" = {2}]",
                                Count, Key, ex.Data[Key]);

                    Console.ReadKey();
                }
            }
        }
    }
}

namespace Common.FluentValidation
{
    public static partial class Validate
    {
        /// <summary>
        /// Validates the passed in parameter matches at least one of the passed in comparisons.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="p_parameter">Parameter to validate.</param>
        /// <param name="p_comparisons">Values to compare against.</param>
        /// <returns>True if a match is found.</returns>
        /// <exception cref="ArgumentNullException"></exception>
        public static bool IsAnyOf<T>(this T p_parameter, params T[] p_comparisons)
        {
            // Validate
            p_parameter
                .CannotBeNull("p_parameter");
            p_comparisons
                .CannotBeNullOrEmpty("p_comparisons");

            // Test for any match
            foreach (var item in p_comparisons)
                if (p_parameter.Equals(item))
                    return true;

            // Return no matches found
            return false;
        }

        /// <summary>
        /// Validates if any passed in parameter is equal to null.
        /// </summary>
        /// <param name="p_parameters">Parameters to test for Null.</param>
        /// <returns>True if one or more parameters are null.</returns>
        public static bool IsAnyNull(params object[] p_parameters)
        {
            p_parameters
                .CannotBeNullOrEmpty("p_parameters");

            foreach (var item in p_parameters)
                if (item == null)
                    return true;

            return false;
        }
    }
}

namespace Common.FluentValidation
{
    public static partial class Validate
    {
        /// <summary>
        /// Validates the passed in parameter is not null, throwing a detailed exception message if the test fails.
        /// </summary>
        /// <param name="p_parameter">Parameter to validate.</param>
        /// <param name="p_name">Name of tested parameter to assist with debugging.</param>
        /// <exception cref="ArgumentNullException"></exception>
        public static void CannotBeNull(this object p_parameter, string p_name)
        {
            if (p_parameter == null)
                throw
                    new
                        ArgumentNullException(
                        string.Format("Parameter \"{0}\" cannot be null.",
                        p_name), default(Exception));
        }
    }
}

namespace Common.FluentValidation
{
    public static partial class Validate
    {
        /// <summary>
        /// Validates the passed in parameter is not null or an empty collection, throwing a detailed exception message if the test fails.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="p_parameter">Parameter to validate.</param>
        /// <param name="p_name">Name of tested parameter to assist with debugging.</param>
        /// <exception cref="ArgumentNullException"></exception>
        /// <exception cref="ArgumentOutOfRangeException"></exception>
        public static void CannotBeNullOrEmpty<T>(this ICollection<T> p_parameter, string p_name)
        {
            if (p_parameter == null)
                throw new ArgumentNullException("Collection cannot be null.\r\nParameter_Name: " + p_name, default(Exception));

            if (p_parameter.Count <= 0)
                throw new ArgumentOutOfRangeException("Collection cannot be empty.\r\nParameter_Name: " + p_name, default(Exception));
        }

        /// <summary>
        /// Validates the passed in parameter is not null or empty, throwing a detailed exception message if the test fails.
        /// </summary>
        /// <param name="p_parameter">Parameter to validate.</param>
        /// <param name="p_name">Name of tested parameter to assist with debugging.</param>
        /// <exception cref="ArgumentException"></exception>
        public static void CannotBeNullOrEmpty(this string p_parameter, string p_name)
        {
            if (string.IsNullOrEmpty(p_parameter))
                throw new ArgumentException("String cannot be null or empty.\r\nParameter_Name: " + p_name, default(Exception));
        }
    }
}

Two Sample NUnit Unit Tests

Matching behaviour for Exception types is exact (ie. A child IS NOT a match for any of its parent types).

using System;
using System.Collections.Generic;
using Common.FluentValidation;
using NUnit.Framework;

namespace UnitTests.Common.Fluent_Validations
{
    [TestFixture]
    public class IsAnyOf_Tests
    {
        [Test, ExpectedException(typeof(ArgumentNullException))]
        public void IsAnyOf_ArgumentNullException_ShouldNotMatch_ArgumentException_Test()
        {
            Action TestMethod = () => { throw new ArgumentNullException(); };

            try
            {
                TestMethod();
            }
            catch (Exception ex)
            {
                if (ex.GetType().IsAnyOf(
                    typeof(ArgumentException), /*Note: ArgumentNullException derrived from ArgumentException*/
                    typeof(FormatException),
                    typeof(KeyNotFoundException)))
                {
                    // Handle expected Exceptions
                    return;
                }

                //else throw original
                throw;
            }
        }

        [Test, ExpectedException(typeof(OutOfMemoryException))]
        public void IsAnyOf_OutOfMemoryException_ShouldMatch_OutOfMemoryException_Test()
        {
            Action TestMethod = () => { throw new OutOfMemoryException(); };

            try
            {
                TestMethod();
            }
            catch (Exception ex)
            {
                if (ex.GetType().IsAnyOf(
                    typeof(OutOfMemoryException),
                    typeof(StackOverflowException)))
                    throw;

                /*else... Handle other exception types, typically by logging to file*/
            }
        }
    }
}

How to update UI from another thread running in another class

If this is a long calculation then I would go background worker. It has progress support. It also has support for cancel.

http://msdn.microsoft.com/en-us/library/cc221403(v=VS.95).aspx

Here I have a TextBox bound to contents.

    private void backgroundWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        Debug.Write("backgroundWorker_RunWorkerCompleted");
        if (e.Cancelled)
        {
            contents = "Cancelled get contents.";
            NotifyPropertyChanged("Contents");
        }
        else if (e.Error != null)
        {
            contents = "An Error Occured in get contents";
            NotifyPropertyChanged("Contents");
        }
        else
        {
            contents = (string)e.Result;
            if (contentTabSelectd) NotifyPropertyChanged("Contents");
        }
    }

Difference between Git and GitHub

Github is required if you want to collaborate across developers. If you are a single contributor git is enough, make sure you backup your code on regular basis

Programmatically change the height and width of a UIImageView Xcode Swift

A faster / alternative way to change the height and/or width of a UIView is by setting its width/height through frame.size:

let neededHeight = UIScreen.main.bounds.height * 0.2
yourView.frame.size.height = neededHeight

How to specify function types for void (not Void) methods in Java8?

When you need to accept a function as argument which takes no arguments and returns no result (void), in my opinion it is still best to have something like

  public interface Thunk { void apply(); }

somewhere in your code. In my functional programming courses the word 'thunk' was used to describe such functions. Why it isn't in java.util.function is beyond my comprehension.

In other cases I find that even when java.util.function does have something that matches the signature I want - it still doesn't always feel right when the naming of the interface doesn't match the use of the function in my code. I guess it's a similar point that is made elsewhere here regarding 'Runnable' - which is a term associated with the Thread class - so while it may have he signature I need, it is still likely to confuse the reader.

Difference between a virtual function and a pure virtual function

For a virtual function you need to provide implementation in the base class. However derived class can override this implementation with its own implementation. Normally , for pure virtual functions implementation is not provided. You can make a function pure virtual with =0 at the end of function declaration. Also, a class containing a pure virtual function is abstract i.e. you can not create a object of this class.

Best practice for Django project working directory structure

You can use https://github.com/Mischback/django-project-skeleton repository.

Run below command:

$ django-admin startproject --template=https://github.com/Mischback/django-project-skeleton/archive/development.zip [projectname]

The structure is something like this:

[projectname]/                  <- project root
+-- [projectname]/              <- Django root
¦   +-- __init__.py
¦   +-- settings/
¦   ¦   +-- common.py
¦   ¦   +-- development.py
¦   ¦   +-- i18n.py
¦   ¦   +-- __init__.py
¦   ¦   +-- production.py
¦   +-- urls.py
¦   +-- wsgi.py
+-- apps/
¦   +-- __init__.py
+-- configs/
¦   +-- apache2_vhost.sample
¦   +-- README
+-- doc/
¦   +-- Makefile
¦   +-- source/
¦       +-- *snap*
+-- manage.py
+-- README.rst
+-- run/
¦   +-- media/
¦   ¦   +-- README
¦   +-- README
¦   +-- static/
¦       +-- README
+-- static/
¦   +-- README
+-- templates/
    +-- base.html
    +-- core
    ¦   +-- login.html
    +-- README

How to delete files recursively from an S3 bucket

With s3cmd package installed on a Linux machine, you can do this

s3cmd rm s3://foo/bar --recursive

javascript function wait until another function to finish

In my opinion, deferreds/promises (as you have mentionned) is the way to go, rather than using timeouts.

Here is an example I have just written to demonstrate how you could do it using deferreds/promises.

Take some time to play around with deferreds. Once you really understand them, it becomes very easy to perform asynchronous tasks.

Hope this helps!

$(function(){
    function1().done(function(){
        // function1 is done, we can now call function2
        console.log('function1 is done!');

        function2().done(function(){
            //function2 is done
            console.log('function2 is done!');
        });
    });
});

function function1(){
    var dfrd1 = $.Deferred();
    var dfrd2= $.Deferred();

    setTimeout(function(){
        // doing async stuff
        console.log('task 1 in function1 is done!');
        dfrd1.resolve();
    }, 1000);

    setTimeout(function(){
        // doing more async stuff
        console.log('task 2 in function1 is done!');
        dfrd2.resolve();
    }, 750);

    return $.when(dfrd1, dfrd2).done(function(){
        console.log('both tasks in function1 are done');
        // Both asyncs tasks are done
    }).promise();
}

function function2(){
    var dfrd1 = $.Deferred();
    setTimeout(function(){
        // doing async stuff
        console.log('task 1 in function2 is done!');
        dfrd1.resolve();
    }, 2000);
    return dfrd1.promise();
}

Correct location of openssl.cnf file

On my CentOS 6 I have two openssl.cnf :

/openvpn/easy-rsa/
/pki/tls/

Java get month string from integer

Month enum

You could use the Month enum. This enum is defined as part of the new java.time framework built into Java 8 and later.

int monthNumber = 10;
Month.of(monthNumber).name();

The output would be:

OCTOBER

Localize

Localize to a language beyond English by calling getDisplayName on the same Enum.

String output = Month.OCTOBER.getDisplayName ( TextStyle.FULL , Locale.CANADA_FRENCH );

output:

octobre

How to get an array of specific "key" in multidimensional array without looping

You can also use array_reduce() if you prefer a more functional approach

For instance:

$userNames = array_reduce($users, function ($carry, $user) {
    array_push($carry, $user['name']);
    return $carry;
}, []);

Or if you like to be fancy,

$userNames = [];
array_map(function ($user) use (&$userNames){
    $userNames[]=$user['name'];
}, $users);

This and all the methods above do loop behind the scenes though ;)

Angular/RxJs When should I unsubscribe from `Subscription`

I like the last two answers, but I experienced an issue if the the subclass referenced "this" in ngOnDestroy.

I modified it to be this, and it looks like it resolved that issue.

export abstract class BaseComponent implements OnDestroy {
    protected componentDestroyed$: Subject<boolean>;
    constructor() {
        this.componentDestroyed$ = new Subject<boolean>();
        let f = this.ngOnDestroy;
        this.ngOnDestroy = function()  {
            // without this I was getting an error if the subclass had
            // this.blah() in ngOnDestroy
            f.bind(this)();
            this.componentDestroyed$.next(true);
            this.componentDestroyed$.complete();
        };
    }
    /// placeholder of ngOnDestroy. no need to do super() call of extended class.
    ngOnDestroy() {}
}

downloading all the files in a directory with cURL

If you're not bound to curl, you might want to use wget in recursive mode but restricting it to one level of recursion, try the following;

wget --no-verbose --no-parent --recursive --level=1\
--no-directories --user=login --password=pass ftp://ftp.myftpsite.com/
  • --no-parent : Do not ever ascend to the parent directory when retrieving recursively.
  • --level=depth : Specify recursion maximum depth level depth. The default maximum depth is five layers.
  • --no-directories : Do not create a hierarchy of directories when retrieving recursively.

Using bind variables with dynamic SELECT INTO clause in PL/SQL

Select Into functionality only works for PL/SQL Block, when you use Execute immediate , oracle interprets v_query_str as a SQL Query string so you can not use into .will get keyword missing Exception. in example 2 ,we are using begin end; so it became pl/sql block and its legal.

Delete with "Join" in Oracle sql Query

Use a subquery in the where clause. For a delete query requirig a join, this example will delete rows that are unmatched in the joined table "docx_document" and that have a create date > 120 days in the "docs_documents" table.

delete from docs_documents d
where d.id in (
    select a.id from docs_documents a
    left join docx_document b on b.id = a.document_id
    where b.id is null
        and floor(sysdate - a.create_date) > 120
 );

Closing Twitter Bootstrap Modal From Angular Controller

You can do it with a simple jquery code.

$('#Mymodal').modal('hide');

How to generate random number in Bash?

I wrote several articles on this.

$ RANDOM=$(date +%s%N | cut -b10-19)
$ echo $(( $RANDOM % 113 + 13 ))

The above will give a number between 13 and 113, with reasonable random entropy.

How to assign a heredoc value to a variable in Bash?

Branching off Neil's answer, you often don't need a var at all, you can use a function in much the same way as a variable and it's much easier to read than the inline or read-based solutions.

$ complex_message() {
  cat <<'EOF'
abc'asdf"
$(dont-execute-this)
foo"bar"''
EOF
}

$ echo "This is a $(complex_message)"
This is a abc'asdf"
$(dont-execute-this)
foo"bar"''

How can I add private key to the distribution certificate?

What i did is that , i created a new certificate for distribution form my Mac computer and gave signing identity from this Mac computer as well, and thats it

Multiple submit buttons on HTML form – designate one button as default

Another solution, using jQuery:

$(document).ready(function() {
  $("input").keypress(function(e) {
    if (e.which == 13) {
      $('#submit').click();
      return false;
    }

    return true;
  });
});

This should work on the following forms, making "Update" the default action:

<form name="f" method="post" action="/action">
  <input type="text" name="text1" />
  <input type="submit" name="button2" value="Delete" />
  <input type="submit" name="button1" id="submit" value="Update" />
</form>

As well as:

<form name="f" method="post" action="/action">
  <input type="text" name="text1" />
  <button type="submit" name="button2">Delete</button>
  <button type="submit" name="button1" id="submit">Update</button>
</form>

This traps the Enter key only when an input field on the form has focus.

Javascript how to split newline

The problem is that when you initialize ks, the value hasn't been set.

You need to fetch the value when user submits the form. So you need to initialize the ks inside the callback function

(function($){
   $(document).ready(function(){
      $('#data').submit(function(e){
      //Here it will fetch the value of #keywords
         var ks = $('#keywords').val().split("\n");
         ...
      });
   });
})(jQuery);

Is a Java hashmap search really O(1)?

Only in theoretical case, when hashcodes are always different and bucket for every hash code is also different, the O(1) will exist. Otherwise, it is of constant order i.e. on increment of hashmap, its order of search remains constant.

Using pip behind a proxy with CNTLM

Set the following environment variable: export PIP_PROXY=http://web-proxy.mydomain.com

More than one file was found with OS independent path 'META-INF/LICENSE'

For me, I was using someone's project and I was having issue compiling the lib.

The solution to add packagingOptions didn't helped because it would prevent compiling latest .so file of armeabi-v7a and will copy the .so file from jniLibs to the built APK file

I deleted the jniLibs folder from \app\src\main and it solved the problem

Project file view in Android Studio

Is there a goto statement in Java?

I'm not a fan of goto either, as it usually makes code less readable. However I do believe that there are exceptions to that rule (especially when it comes to lexers and parsers!)

Of Course you can always bring your program into Kleene Normalform by translating it to something assembler-like and then write something like

int line = 1;
boolean running = true;
while(running)
{
    switch(line++)
    {
        case 1: /* line 1 */
                break;
        case 2: /* line 2 */
                break;
        ...
        case 42: line = 1337; // goto 1337
                break;
        ...
        default: running = false;
                break;
    }
}

(So you basically write a VM that executes your binary code... where line corresponds to the instruction pointer)

That is so much more readable than code that uses goto, isn't it?

Can a table row expand and close?

Well, I'd say use the DIV instead of table as it would be much easier (but there's nothing wrong with using tables).

My approach would be to use jQuery.ajax and request more data from server and that way, the selected DIV (or TD if you use table) will automatically expand based on requested content.

That way, it saves bandwidth and makes it go faster as you don't load all content at once. It loads only when it's selected.

What is the correct way to start a mongod service on linux / OS X?

With recent builds of mongodb community edition, this is straightforward.

When you install via brew, it tells you what exactly to do. There is no need to create a new launch control file.

$ brew install mongodb
==> Downloading https://homebrew.bintray.com/bottles/mongodb-3.0.6.yosemite.bottle.tar.gz ### 100.0%
==> Pouring mongodb-3.0.6.yosemite.bottle.tar.gz
==> Caveats
To have launchd start mongodb at login:
  ln -sfv /usr/local/opt/mongodb/*.plist ~/Library/LaunchAgents
Then to load mongodb now:
  launchctl load ~/Library/LaunchAgents/homebrew.mxcl.mongodb.plist
Or, if you don't want/need launchctl, you can just run:
  mongod --config /usr/local/etc/mongod.conf
==> Summary
  /usr/local/Cellar/mongodb/3.0.6: 17 files, 159M

'Framework not found' in Xcode

I realised that I hadn't run/built my framework with the Generic Device, which strangely lead to these issues. I just put the framework back in and it worked.

How to list AD group membership for AD users using input list?

Get-ADPrincipalGroupMembership username | select name

Got it from another answer but the script works magic. :)

Returning a boolean from a Bash function

Use the true or false commands immediately before your return, then return with no parameters. The return will automatically use the value of your last command.

Providing arguments to return is inconsistent, type specific and prone to error if you are not using 1 or 0. And as previous comments have stated, using 1 or 0 here is not the right way to approach this function.

#!/bin/bash

function test_for_cat {
    if [ $1 = "cat" ];
    then
        true
        return
    else
        false
        return
    fi
}

for i in cat hat;
do
    echo "${i}:"
    if test_for_cat "${i}";
    then
        echo "- True"
    else
        echo "- False"
    fi
done

Output:

$ bash bash_return.sh

cat:
- True
hat:
- False

What is the difference between instanceof and Class.isAssignableFrom(...)?

Talking in terms of performance "2" (with JMH):

class A{}
class B extends A{}

public class InstanceOfTest {

public static final Object a = new A();
public static final Object b = new B();

@Benchmark
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
public boolean testInstanceOf()
{
    return b instanceof A;
}

@Benchmark
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
public boolean testIsInstance()
{
    return A.class.isInstance(b);
}

@Benchmark
@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.NANOSECONDS)
public boolean testIsAssignableFrom()
{
    return A.class.isAssignableFrom(b.getClass());
}

public static void main(String[] args) throws RunnerException {
    Options opt = new OptionsBuilder()
            .include(InstanceOfTest.class.getSimpleName())
            .warmupIterations(5)
            .measurementIterations(5)
            .forks(1)
            .build();

    new Runner(opt).run();
}
}

It gives:

Benchmark                            Mode  Cnt  Score   Error  Units
InstanceOfTest.testInstanceOf        avgt    5  1,972 ? 0,002  ns/op
InstanceOfTest.testIsAssignableFrom  avgt    5  1,991 ? 0,004  ns/op
InstanceOfTest.testIsInstance        avgt    5  1,972 ? 0,003  ns/op

So that we can conclude: instanceof as fast as isInstance() and isAssignableFrom() not far away (+0.9% executon time). So no real difference whatever you choose

How to compare the contents of two string objects in PowerShell

You want to do $arrayOfString[0].Title -eq $myPbiject.item(0).Title

-match is for regex matching ( the second argument is a regex )

how to solve Error cannot add duplicate collection entry of type add with unique key attribute 'value' in iis 7

All you need is a <clear /> tag. Here's an example:

<configuration>
  <system.webServer>
    <defaultDocument>
      <files>
        <clear />
        <add value="default.aspx" />
      </files>
    </defaultDocument>
  </system.webServer>
</configuration>

How does Subquery in select statement work in oracle

It's simple-

SELECT empname,
       empid,
       (SELECT COUNT (profileid)
          FROM profile
         WHERE profile.empid = employee.empid)
           AS number_of_profiles
  FROM employee;

It is even simpler when you use a table join like this:

  SELECT e.empname, e.empid, COUNT (p.profileid) AS number_of_profiles
    FROM employee e LEFT JOIN profile p ON e.empid = p.empid
GROUP BY e.empname, e.empid;

Explanation for the subquery:

Essentially, a subquery in a select gets a scalar value and passes it to the main query. A subquery in select is not allowed to pass more than one row and more than one column, which is a restriction. Here, we are passing a count to the main query, which, as we know, would always be only a number- a scalar value. If a value is not found, the subquery returns null to the main query. Moreover, a subquery can access columns from the from clause of the main query, as shown in my query where employee.empid is passed from the outer query to the inner query.


Edit:

When you use a subquery in a select clause, Oracle essentially treats it as a left join (you can see this in the explain plan for your query), with the cardinality of the rows being just one on the right for every row in the left.


Explanation for the left join

A left join is very handy, especially when you want to replace the select subquery due to its restrictions. There are no restrictions here on the number of rows of the tables in either side of the LEFT JOIN keyword.

For more information read Oracle Docs on subqueries and left join or left outer join.

How to select the last record from MySQL table using SQL syntax

SELECT   *
FROM     table
ORDER BY id DESC
LIMIT    0, 1

how to realize countifs function (excel) in R

Given a dataset

df <- data.frame( sex = c('M', 'M', 'F', 'F', 'M'), 
                  occupation = c('analyst', 'dentist', 'dentist', 'analyst', 'cook') )

you can subset rows

df[df$sex == 'M',] # To get all males
df[df$occupation == 'analyst',] # All analysts

etc.

If you want to get number of rows, just call the function nrow such as

nrow(df[df$sex == 'M',])

Uninstall Eclipse under OSX?

Eclipse has no impact on Mac OS beyond it directory, so there is no problem uninstalling.

I think that What you are facing is the result of Eclipse switching the plugin distribution system recently. There are now two redundant and not very compatible means of installing plugins. It's a complete mess. You may be better off (if possible) installing a more recent version of Eclipse (maybe even the 3.5 milestones) as they seem to be more stable in that regard.

HTML iframe - disable scroll

Set all the content to:

#yourContent{
 width:100%;
height:100%;  // in you csss
}

The thing is that the iframe scroll is set by the content NOT by the iframe by itself.

set the content to 100% in the interior with CSS and the desired for the iframe in HTML

Can we create an instance of an interface in Java?

Normaly, you can create a reference for an interface. But you cant create an instance for interface.

Remove object from a list of objects in python

In python there are no arrays, lists are used instead. There are various ways to delete an object from a list:

my_list = [1,2,4,6,7]

del my_list[1] # Removes index 1 from the list
print my_list # [1,4,6,7]
my_list.remove(4) # Removes the integer 4 from the list, not the index 4
print my_list # [1,6,7]
my_list.pop(2) # Removes index 2 from the list

In your case the appropriate method to use is pop, because it takes the index to be removed:

x = object()
y = object()
array = [x, y]
array.pop(0)
# Using the del statement
del array[0]

Import Error: No module named numpy

I was trying to use NumPy in Intellij but was facing the same issue so, I figured out that NumPy also comes with pandas. So, I installed pandas with IntelliJ tip and later on was able to import NumPy. Might help someone someday!

Understanding the Rails Authenticity Token

What is an authentication_token ?

This is a random string used by rails application to make sure that the user is requesting or performing an action from the app page, not from another app or site.

Why is an authentication_token is necessary ?

To protect your app or site from cross-site request forgery.

How to add an authentication_token to a form ?

If you are generating a form using form_for tag an authentication_token is automatically added else you can use <%= csrf_meta_tag %>.

Split large string in n-size chunks in JavaScript

I created several faster variants which you can see on jsPerf. My favorite one is this:

function chunkSubstr(str, size) {
  const numChunks = Math.ceil(str.length / size)
  const chunks = new Array(numChunks)

  for (let i = 0, o = 0; i < numChunks; ++i, o += size) {
    chunks[i] = str.substr(o, size)
  }

  return chunks
}

How to insert array of data into mysql using php

if(is_array($EMailArr)){
    foreach($EMailArr as $key => $value){

    $R_ID = (int) $value['R_ID'];
    $email = mysql_real_escape_string( $value['email'] );
    $name = mysql_real_escape_string( $value['name'] );

    $sql = "INSERT INTO email_list (R_ID, EMAIL, NAME) values ('$R_ID', '$email', '$name')";
    mysql_query($sql) or exit(mysql_error()); 
    }
}

A better example solution with PDO:

 $q = $sql->prepare("INSERT INTO `email_list` 
                     SET `R_ID` = ?, `EMAIL` = ?, `NAME` = ?");

 foreach($EMailArr as $value){
   $q ->execute( array( $value['R_ID'], $value['email'], $value['name'] ));
 }

Position a div container on the right side

  • Use float: right to.. float the second column to the.. right.
  • Use overflow: hidden to clear the floats so that the background color I just put in will be visible.

Live Demo

#wrapper{
    background:#000;
    overflow: hidden
}
#c1 {
   float:left;
   background:red;
}
#c2 {
    background:green;
    float: right
}

How to add text inside the doughnut chart using Chart.js?

@rap-2-h and @Ztuons Ch's answer doesn't allow for the showTooltips option to be active, but what you can do is create and layer a second canvas object behind the one rendering the chart.

The important part is the styling required in the divs and for the canvas object itself so that they render on top of each other.

_x000D_
_x000D_
var data = [_x000D_
    {value : 100, color : 'rgba(226,151,093,1)', highlight : 'rgba(226,151,093,0.75)', label : "Sector 1"},_x000D_
    {value : 100, color : 'rgba(214,113,088,1)', highlight : 'rgba(214,113,088,0.75)', label : "Sector 2"},_x000D_
    {value : 100, color : 'rgba(202,097,096,1)', highlight : 'rgba(202,097,096,0.75)', label : "Sector 3"}_x000D_
]_x000D_
_x000D_
var options = { showTooltips : true };_x000D_
     _x000D_
var total = 0;_x000D_
for (i = 0; i < data.length; i++) {_x000D_
     total = total + data[i].value;_x000D_
}_x000D_
_x000D_
var chartCtx = $("#canvas").get(0).getContext("2d");_x000D_
var chart = new Chart(chartCtx).Doughnut(data, options);_x000D_
_x000D_
var textCtx = $("#text").get(0).getContext("2d");_x000D_
textCtx.textAlign = "center";_x000D_
textCtx.textBaseline = "middle";_x000D_
textCtx.font = "30px sans-serif";_x000D_
textCtx.fillText(total, 150, 150);
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<script src="//cdnjs.cloudflare.com/ajax/libs/Chart.js/1.0.2/Chart.min.js"></script>_x000D_
<html>_x000D_
<body>_x000D_
<div style="position: relative; width:300px; height:300px;">_x000D_
    <canvas id="text" _x000D_
            style="z-index: 1; _x000D_
                   position: absolute;_x000D_
                   left: 0px; _x000D_
                   top: 0px;" _x000D_
            height="300" _x000D_
            width="300"></canvas>_x000D_
    <canvas id="canvas" _x000D_
            style="z-index: 2; _x000D_
                   position: absolute;_x000D_
                   left: 0px; _x000D_
                   top: 0px;" _x000D_
            height="300" _x000D_
            width="300"></canvas>_x000D_
</div>_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Here's the jsfiddle: https://jsfiddle.net/68vxqyak/1/

EXC_BAD_ACCESS signal received

How i deal with EXC_BAD_ACCESS

Sometimes i feel that when a EXC_BAD_ACCESS error is thrown xcode will show the error in the main.m class giving no extra information of where the crash happens(Sometimes).

In those times we can set a Exceptional Breakpoint in Xcode so that when exception is caught a breakpoint will be placed and will directly intimate the user that crash has happened in that line

enter image description here

How to write MySQL query where A contains ( "a" or "b" )

Two options:

  1. Use the LIKE keyword, along with percent signs in the string

    select * from table where field like '%a%' or field like '%b%'.
    

    (note: If your search string contains percent signs, you'll need to escape them)

  2. If you're looking for more a complex combination of strings than you've specified in your example, you could regular expressions (regex):

    See the MySQL manual for more on how to use them: http://dev.mysql.com/doc/refman/5.1/en/regexp.html

Of these, using LIKE is the most usual solution -- it's standard SQL, and in common use. Regex is less commonly used but much more powerful.

Note that whichever option you go with, you need to be aware of possible performance implications. Searching for sub-strings like this will mean that the query will have to scan the entire table. If you have a large table, this could make for a very slow query, and no amount of indexing is going to help.

If this is an issue for you, and you'r going to need to search for the same things over and over, you may prefer to do something like adding a flag field to the table which specifies that the string field contains the relevant sub-strings. If you keep this flag field up-to-date when you insert of update a record, you could simply query the flag when you want to search. This can be indexed, and would make your query much much quicker. Whether it's worth the effort to do that is up to you, it'll depend on how bad the performance is using LIKE.

IPython Notebook save location

If you're using IPython 4.x/Jupyter, run

$ jupyter notebook --generate-config

This will create a file jupyter_notebook_config.py in ~/.jupyter. This file already has a line starting with # c.NotebookApp.notebook_dir=u''.

All you need to do is to uncomment this line and change the value to your desired location, e.g., c.NotebookApp.notebook_dir=u'/home/alice/my_ipython_notebooks'

How do I get the directory of the PowerShell script I execute?

PowerShell 3 has the $PSScriptRoot automatic variable:

Contains the directory from which a script is being run.

In Windows PowerShell 2.0, this variable is valid only in script modules (.psm1). Beginning in Windows PowerShell 3.0, it is valid in all scripts.

Don't be fooled by the poor wording. PSScriptRoot is the directory of the current file.

In PowerShell 2, you can calculate the value of $PSScriptRoot yourself:

# PowerShell v2
$PSScriptRoot = Split-Path -Parent -Path $MyInvocation.MyCommand.Definition

Matrix multiplication using arrays

Try this,

public static Double[][] multiplicar(Double A[][],Double B[][]){
    Double[][] C= new Double[2][2];
    int i,j,k;
     for (i = 0; i < 2; i++) {
         for (j = 0; j < 2; j++) {
             C[i][j] = 0.00000;
         }
     }
    for(i=0;i<2;i++){
        for(j=0;j<2;j++){
            for (k=0;k<2;k++){
                  C[i][j]+=(A[i][k]*B[k][j]);

            }

        }
    }
    return C;
}

Add a property to a JavaScript object using a variable as the name?

You can even make List of objects like this

var feeTypeList = [];
$('#feeTypeTable > tbody > tr').each(function (i, el) {
    var feeType = {};

    var $ID = $(this).find("input[id^=txtFeeType]").attr('id');

    feeType["feeTypeID"] = $('#ddlTerm').val();
    feeType["feeTypeName"] = $('#ddlProgram').val();
    feeType["feeTypeDescription"] = $('#ddlBatch').val();

    feeTypeList.push(feeType);
});

Multiple returns from a function

Best Practice is to put your returned variables into array and then use list() to assign array values to variables.

<?php

function add_subt($val1, $val2) {
    $add = $val1 + $val2;
    $subt = $val1 - $val2;

    return array($add, $subt);
}

list($add_result, $subt_result) = add_subt(20, 7);
echo "Add: " . $add_result . '<br />';
echo "Subtract: " . $subt_result . '<br />';

?>

How do I remove the horizontal scrollbar in a div?

If you don't have anything overflowing horizontally, you can also just use

overflow: auto;

and it will only show scrollbars when needed.

See The CSS Overflow Property

How do I prevent 'git diff' from using a pager?

As a previous answer mentioned, passing the -F option to less causes it to quit if the content is less than one screen. However, after doing so, the screen is reset, and you end up not seeing the content.

The -X option does away with that behaviour. So, I use the following to enable conditional paging based on the amount of content:

git config --global --replace-all core.pager "less -F -X"

Parse json string to find and element (key / value)

Use a JSON parser, like JSON.NET

string json = "{ \"Atlantic/Canary\": \"GMT Standard Time\", \"Europe/Lisbon\": \"GMT Standard Time\", \"Antarctica/Mawson\": \"West Asia Standard Time\", \"Etc/GMT+3\": \"SA Eastern Standard Time\", \"Etc/GMT+2\": \"UTC-02\", \"Etc/GMT+1\": \"Cape Verde Standard Time\", \"Etc/GMT+7\": \"US Mountain Standard Time\", \"Etc/GMT+6\": \"Central America Standard Time\", \"Etc/GMT+5\": \"SA Pacific Standard Time\", \"Etc/GMT+4\": \"SA Western Standard Time\", \"Pacific/Wallis\": \"UTC+12\", \"Europe/Skopje\": \"Central European Standard Time\", \"America/Coral_Harbour\": \"SA Pacific Standard Time\", \"Asia/Dhaka\": \"Bangladesh Standard Time\", \"America/St_Lucia\": \"SA Western Standard Time\", \"Asia/Kashgar\": \"China Standard Time\", \"America/Phoenix\": \"US Mountain Standard Time\", \"Asia/Kuwait\": \"Arab Standard Time\" }";
var data = (JObject)JsonConvert.DeserializeObject(json);
string timeZone = data["Atlantic/Canary"].Value<string>();

Get bitcoin historical data

I have written a java example for this case:

Use json.org library to retrieve JSONObjects and JSONArrays. The example below uses blockchain.info's data which can be obtained as JSONObject.

    public class main 
    {
        public static void main(String[] args) throws MalformedURLException, IOException
        {
            JSONObject data = getJSONfromURL("https://blockchain.info/charts/market-price?format=json");
            JSONArray data_array = data.getJSONArray("values");

            for (int i = 0; i < data_array.length(); i++)
            {
                JSONObject price_point = data_array.getJSONObject(i);

                //  Unix time
                int x = price_point.getInt("x");

                //  Bitcoin price at that time
                double y = price_point.getDouble("y");

                //  Do something with x and y.
            }

        }

        public static JSONObject getJSONfromURL(String URL)
        {
            try
            {
                URLConnection uc;
                URL url = new URL(URL);
                uc = url.openConnection();
                uc.setConnectTimeout(10000);
                uc.addRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)");
                uc.connect();

                BufferedReader rd = new BufferedReader(
                        new InputStreamReader(uc.getInputStream(), 
                        Charset.forName("UTF-8")));

                StringBuilder sb = new StringBuilder();
                int cp;
                while ((cp = rd.read()) != -1)
                {
                    sb.append((char)cp);
                }

                String jsonText = (sb.toString());            

                return new JSONObject(jsonText.toString());
            } catch (IOException ex)
            {
                return null;
            }
        }
    }

List<T> OrderBy Alphabetical Order

If you mean an in-place sort (i.e. the list is updated):

people.Sort((x, y) => string.Compare(x.LastName, y.LastName));

If you mean a new list:

var newList = people.OrderBy(x=>x.LastName).ToList(); // ToList optional

ASP.NET MVC on IIS 7.5

We had a MVC application moved to a new server. .NET 4 and MVC 3 was installed, but we still got “Error 403.14". In this case, this meant that IIS did not understand that it was dealing with a MVC application, it was looking for the default page.

The solution was simple: HTTP Redirection was not installed on the server.

Server Manager – Roles – Web Server (IIS) – Roles Services – HTTP Redirection: Not installed. Installed it, problem solved.

changing visibility using javascript

function loadpage (page_request, containerid)
{
  var loading = document.getElementById ( "loading" ) ;

  // when connecting to server
  if ( page_request.readyState == 1 )
      loading.style.visibility = "visible" ;

  // when loaded successfully
  if (page_request.readyState == 4 && (page_request.status==200 || window.location.href.indexOf("http")==-1))
  {
      document.getElementById(containerid).innerHTML=page_request.responseText ;
      loading.style.visibility = "hidden" ;
  }
}

Get all files and directories in specific path fast

I know this is old, but... Another option may be to use the FileSystemWatcher like so:

void SomeMethod()
{
    System.IO.FileSystemWatcher m_Watcher = new System.IO.FileSystemWatcher();
    m_Watcher.Path = path;
    m_Watcher.Filter = "*.*";
    m_Watcher.NotifyFilter = m_Watcher.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite | NotifyFilters.FileName | NotifyFilters.DirectoryName;
    m_Watcher.Created += new FileSystemEventHandler(OnChanged);
    m_Watcher.EnableRaisingEvents = true;
}

private void OnChanged(object sender, FileSystemEventArgs e)
    {
        string path = e.FullPath;

        lock (listLock)
        {
            pathsToUpload.Add(path);
        }
    }

This would allow you to watch the directories for file changes with an extremely lightweight process, that you could then use to store the names of the files that changed so that you could back them up at the appropriate time.

Difference between web reference and service reference?

The service reference is the newer interface for adding references to all manner of WCF services (they may not be web services) whereas Web reference is specifically concerned with ASMX web references.

You can access web references via the advanced options in add service reference (if I recall correctly).

I'd use service reference because as I understand it, it's the newer mechanism of the two.

Check if string is in a pandas dataframe

a['Names'].str.contains('Mel') will return an indicator vector of boolean values of size len(BabyDataSet)

Therefore, you can use

mel_count=a['Names'].str.contains('Mel').sum()
if mel_count>0:
    print ("There are {m} Mels".format(m=mel_count))

Or any(), if you don't care how many records match your query

if a['Names'].str.contains('Mel').any():
    print ("Mel is there")

Read file-contents into a string in C++

This depends on a lot of things, such as what is the size of the file, what is its type (text/binary) etc. Some time ago I benchmarked the following function against versions using streambuf iterators - it was about twice as fast:

unsigned int FileRead( std::istream & is, std::vector <char> & buff ) {
    is.read( &buff[0], buff.size() );
    return is.gcount();
}

void FileRead( std::ifstream & ifs, string & s ) {
    const unsigned int BUFSIZE = 64 * 1024; // reasoable sized buffer
    std::vector <char> buffer( BUFSIZE );

    while( unsigned int n = FileRead( ifs, buffer ) ) {
        s.append( &buffer[0], n );
    }
}

Adding close button in div to close the box

You can use this jsFiddle

And HTML:

<div id="previewBox">
    <button id="closeButton">Close</button>
<a class="fragment" href="google.com">
    <div>
    <img src ="http://placehold.it/116x116" alt="some description"/> 
    <h3>the title will go here</h3>
        <h4> www.myurlwill.com </h4>
    <p class="text">
        this is a short description yada yada peanuts etc this is a short description yada yada peanuts etc this is a short description yada yada peanuts etc this is a short description yada yada peanuts etcthis is a short description yada yada peanuts etc 
    </p>
</div>
</a>
</div>

With JS (jquery required):

$(document).ready(function() {
    $('#closeButton').on('click', function(e) { 
        $('#previewBox').remove(); 
    });
});

How to order a data frame by one descending and one ascending column?

    library(dplyr)
    library(tidyr)
    #supposing you want to arrange column 'c' in descending order and 'd' in ascending order. name of data frame is df
    ## first doing descending
    df<-arrange(df,desc(c))
    ## then the ascending order of col 'd;
    df <-arrange(df,d)

SQL Update to the SUM of its joined values

Use a sub query similar to the below.

UPDATE P
SET extrasPrice = sub.TotalPrice from
BookingPitches p
inner join 
(Select PitchID, Sum(Price) TotalPrice
    from  dbo.BookingPitchExtras
    Where [Required] = 1
    Group by Pitchid
) as Sub
on p.Id = e.PitchId 
where p.BookingId = 1

Export HTML table to pdf using jspdf

Use get(0) instead of html(). In other words, replace

doc.fromHTML($('#htmlTableId').html(), 15, 15, {
    'width': 170,'elementHandlers': specialElementHandlers
});

with

doc.fromHTML($('#htmlTableId').get(0), 15, 15, {
    'width': 170,'elementHandlers': specialElementHandlers
});

.NET Excel Library that can read/write .xls files

You may consider 3rd party tool that called Excel Jetcell .NET component for read/write excel files:

C# sample

// Create New Excel Workbook
ExcelWorkbook Wbook = new ExcelWorkbook();
ExcelCellCollection Cells = Wbook.Worksheets.Add("Sheet1").Cells;

Cells["A1"].Value = "Excel writer example (C#)";
Cells["A1"].Style.Font.Bold = true;
Cells["B1"].Value = "=550 + 5";

// Write Excel XLS file
Wbook.WriteXLS("excel_net.xls");

VB.NET sample

' Create New Excel Workbook
Dim Wbook As ExcelWorkbook = New ExcelWorkbook()
Dim Cells As ExcelCellCollection = Wbook.Worksheets.Add("Sheet1").Cells

Cells("A1").Value = "Excel writer example (C#)"
Cells("A1").Style.Font.Bold = True
Cells("B1").Value = "=550 + 5"

' Write Excel XLS file
Wbook.WriteXLS("excel_net.xls")

How to break out from foreach loop in javascript

Use a for loop instead of .forEach()

var myObj = [{"a": "1","b": null},{"a": "2","b": 5}]
var result = false

for(var call of myObj) {
    console.log(call)
    
    var a = call['a'], b = call['b']
     
    if(a == null || b == null) {
        result = false
        break
    }
}

python: [Errno 10054] An existing connection was forcibly closed by the remote host

I know this is a very old question but it may be that you need to set the request headers. This solved it for me.

For example 'user-agent', 'accept' etc. here is an example with user-agent:

url = 'your-url-here'
headers = {'user-agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.75 Safari/537.36'}
r = requests.get(url, headers=headers)

The controller for path was not found or does not implement IController

In another scenario just I would like to add is In my scenario, the name space was different for controller as it was mistake of copying controller from another project.

How to specify maven's distributionManagement organisation wide?

There's no need for a parent POM.

You can omit the distributionManagement part entirely in your poms and set it either on your build server or in settings.xml.

To do it on the build server, just pass to the mvn command:

-DaltSnapshotDeploymentRepository=snapshots::default::https://YOUR_NEXUS_URL/snapshots
-DaltReleaseDeploymentRepository=releases::default::https://YOUR_NEXUS_URL/releases

See https://maven.apache.org/plugins/maven-deploy-plugin/deploy-mojo.html for details which options can be set.

It's also possible to set this in your settings.xml.

Just create a profile there which is enabled and contains the property.

Example settings.xml:

<settings>
[...]
  <profiles>
    <profile>
      <id>nexus</id>
      <properties>
        <altSnapshotDeploymentRepository>snapshots::default::https://YOUR_NEXUS_URL/snapshots</altSnapshotDeploymentRepository>
        <altReleaseDeploymentRepository>releases::default::https://YOUR_NEXUS_URL/releases</altReleaseDeploymentRepository>
      </properties>
    </profile>
  </profiles>

  <activeProfiles>
    <activeProfile>nexus</activeProfile>
  </activeProfiles>

</settings>

Make sure that credentials for "snapshots" and "releases" are in the <servers> section of your settings.xml

The properties altSnapshotDeploymentRepository and altReleaseDeploymentRepository are introduced with maven-deploy-plugin version 2.8. Older versions will fail with the error message

Deployment failed: repository element was not specified in the POM inside distributionManagement element or in -DaltDeploymentRepository=id::layout::url parameter

To fix this, you can enforce a newer version of the plug-in:

        <build>
          <pluginManagement>
            <plugins>
              <plugin>
                <artifactId>maven-deploy-plugin</artifactId>
                <version>2.8</version>
              </plugin>
            </plugins>
          </pluginManagement>
        </build>

What is the difference between T(n) and O(n)?

There's a simple way (a trick, I guess) to remember which notation means what.

All of the Big-O notations can be considered to have a bar.

When looking at a O, the bar is at the bottom, so it is an (asymptotic) lower bound.

When looking at a T, the bar is obviously in the middle. So it is an (asymptotic) tight bound.

When handwriting O, you usually finish at the top, and draw a squiggle. Therefore O(n) is the upper bound of the function. To be fair, this one doesn't work with most fonts, but it is the original justification of the names.

How and where to use ::ng-deep?

I would emphasize the importance of limiting the ::ng-deep to only children of a component by requiring the parent to be an encapsulated css class.

For this to work it's important to use the ::ng-deep after the parent, not before otherwise it would apply to all the classes with the same name the moment the component is loaded.

Using the :host keyword before ::ng-deep will handle this automatically:

:host ::ng-deep .mat-checkbox-layout

Alternatively you can achieve the same behavior by adding a component scoped CSS class before the ::ng-deep keyword:

.my-component ::ng-deep .mat-checkbox-layout {
    background-color: aqua;
}

Component template:

<h1 class="my-component">
    <mat-checkbox ....></mat-checkbox>
</h1>

Resulting (Angular generated) css will then include the uniquely generated name and apply only to its own component instance:

.my-component[_ngcontent-c1] .mat-checkbox-layout {
    background-color: aqua;
}

pytest cannot import module while python can

I had a similar issue, exact same error, but different cause. I was running the test code just fine, but against an old version of the module. In the previous version of my code one class existed, while the other did not. After updating my code, I should have run the following to install it.

sudo pip install ./ --upgrade

Upon installing the updated module running pytest produced the correct results (because i was using the correct code base).

How can I move all the files from one folder to another using the command line?

This command will move all the files in originalfolder to destinationfolder.

MOVE c:\originalfolder\* c:\destinationfolder

(However it wont move any sub-folders to the new location.)

To lookup the instructions for the MOVE command type this in a windows command prompt:

MOVE /?

FIFO based Queue implementations?

Yeah. Queue

LinkedList being the most trivial concrete implementation.

$(this).serialize() -- How to add a value?

We can do like:

data = $form.serialize() + "&foo=bar";

For example:

var userData = localStorage.getItem("userFormSerializeData");
var userId = localStorage.getItem("userId");

$.ajax({
    type: "POST",
    url: postUrl,
    data: $(form).serialize() + "&" + userData + "&userId=" + userId,
    dataType: 'json',
    success: function (response) {
        //do something
    }
});

Updating user data - ASP.NET Identity

The OWIN context allows you to get the db context. Seems to be working fine so far me, and after all, I got the idea from the ApplciationUserManager class which does the same thing.

    internal void UpdateEmail(HttpContext context, string userName, string email)
    {
        var manager = context.GetOwinContext().GetUserManager<ApplicationUserManager>();
        var user = manager.FindByName(userName);
        user.Email = email;
        user.EmailConfirmed = false;
        manager.Update(user);
        context.GetOwinContext().Get<ApplicationDbContext>().SaveChanges();
    }

Return value in a Bash function

Git Bash on Windows using arrays for multiple return values

BASH CODE:

#!/bin/bash

##A 6-element array used for returning
##values from functions:
declare -a RET_ARR
RET_ARR[0]="A"
RET_ARR[1]="B"
RET_ARR[2]="C"
RET_ARR[3]="D"
RET_ARR[4]="E"
RET_ARR[5]="F"


function FN_MULTIPLE_RETURN_VALUES(){

   ##give the positional arguments/inputs
   ##$1 and $2 some sensible names:
   local out_dex_1="$1" ##output index
   local out_dex_2="$2" ##output index

   ##Echo for debugging:
   echo "running: FN_MULTIPLE_RETURN_VALUES"

   ##Here: Calculate output values:
   local op_var_1="Hello"
   local op_var_2="World"

   ##set the return values:
   RET_ARR[ $out_dex_1 ]=$op_var_1
   RET_ARR[ $out_dex_2 ]=$op_var_2
}


echo "FN_MULTIPLE_RETURN_VALUES EXAMPLES:"
echo "-------------------------------------------"
fn="FN_MULTIPLE_RETURN_VALUES"
out_dex_a=0
out_dex_b=1
eval $fn $out_dex_a $out_dex_b  ##<--Call function
a=${RET_ARR[0]} && echo "RET_ARR[0]: $a "
b=${RET_ARR[1]} && echo "RET_ARR[1]: $b "
echo
##----------------------------------------------##
c="2"
d="3"
FN_MULTIPLE_RETURN_VALUES $c $d ##<--Call function
c_res=${RET_ARR[2]} && echo "RET_ARR[2]: $c_res "
d_res=${RET_ARR[3]} && echo "RET_ARR[3]: $d_res "
echo
##----------------------------------------------##
FN_MULTIPLE_RETURN_VALUES 4 5  ##<---Call function
e=${RET_ARR[4]} && echo "RET_ARR[4]: $e "
f=${RET_ARR[5]} && echo "RET_ARR[5]: $f "
echo
##----------------------------------------------##


read -p "Press Enter To Exit:"

EXPECTED OUTPUT:

FN_MULTIPLE_RETURN_VALUES EXAMPLES:
-------------------------------------------
running: FN_MULTIPLE_RETURN_VALUES
RET_ARR[0]: Hello
RET_ARR[1]: World

running: FN_MULTIPLE_RETURN_VALUES
RET_ARR[2]: Hello
RET_ARR[3]: World

running: FN_MULTIPLE_RETURN_VALUES
RET_ARR[4]: Hello
RET_ARR[5]: World

Press Enter To Exit:

Generate a random double in a range

import java.util.Random;

public class MyClass {
     public static void main(String args[]) {
          Double min = 0.0;  // Set To Your Desired Min Value
          Double max = 10.0; // Set To Your Desired Max Value
          double x = (Math.random() * ((max - min) + 1)) + min;   // This Will Create A Random Number Inbetween Your Min And Max.
          double xrounded = Math.round(x * 100.0) / 100.0;   // Creates Answer To The Nearest 100 th, You Can Modify This To Change How It Rounds.
          System.out.println(xrounded);    // This Will Now Print Out The Rounded, Random Number.
     }
}

What I can do to resolve "1 commit behind master"?

Use

git cherry-pick <commit-hash>

So this will pick your behind commit to git location you are on.

How does a Java HashMap handle different objects with the same hash code?

Your third assertion is incorrect.

It's perfectly legal for two unequal objects to have the same hash code. It's used by HashMap as a "first pass filter" so that the map can quickly find possible entries with the specified key. The keys with the same hash code are then tested for equality with the specified key.

You wouldn't want a requirement that two unequal objects couldn't have the same hash code, as otherwise that would limit you to 232 possible objects. (It would also mean that different types couldn't even use an object's fields to generate hash codes, as other classes could generate the same hash.)

is of a type that is invalid for use as a key column in an index

A solution would be to declare your key as nvarchar(20).

Write Base64-encoded image to file

No need to use BufferedImage, as you already have the image file in a byte array

    byte dearr[] = Base64.decodeBase64(crntImage);
    FileOutputStream fos = new FileOutputStream(new File("c:/decode/abc.bmp")); 
    fos.write(dearr); 
    fos.close();

Cannot serve WCF services in IIS on Windows 8

Seemed to be a no brainer; the WCF service should be enabled using Programs and Features -> Turn Windows features on or off in the Control Panel. Go to .NET Framework Advanced Services -> WCF Services and enable HTTP Activation as described in this blog post on mdsn.

From the command prompt (as admin), you can run:

C:\> DISM /Online /Enable-Feature /FeatureName:WCF-HTTP-Activation
C:\> DISM /Online /Enable-Feature /FeatureName:WCF-HTTP-Activation45

If you get an error then use the below

C:\> DISM /Online /Enable-Feature /all /FeatureName:WCF-HTTP-Activation
C:\> DISM /Online /Enable-Feature /all /FeatureName:WCF-HTTP-Activation45

Change content of div - jQuery

You can try the same with replacewith()

$('.click').click(function() {
    // get the contents of the link that was clicked
    var linkText = $(this).text();

    // replace the contents of the div with the link text
    $('#content-container').replaceWith(linkText);

    // cancel the default action of the link by returning false
    return false;
});

The .replaceWith() method removes content from the DOM and inserts new content in its place with a single call.

ASP.NET Core configuration for .NET Core console application

On .Net Core 3.1 we just need to do these:

static void Main(string[] args)
{
  var configuration = new ConfigurationBuilder().AddJsonFile("appsettings.json").Build();
}

Using SeriLog will look like:

using Microsoft.Extensions.Configuration;
using Serilog;
using System;


namespace yournamespace
{
    class Program
    {

        static void Main(string[] args)
        {
            var configuration = new ConfigurationBuilder().AddJsonFile("appsettings.json").Build();
            Log.Logger = new LoggerConfiguration().ReadFrom.Configuration(configuration).CreateLogger();

            try
            {
                Log.Information("Starting Program.");
            }
            catch (Exception ex)
            {
                Log.Fatal(ex, "Program terminated unexpectedly.");
                return;
            }
            finally
            {
                Log.CloseAndFlush();
            }
        }
    }
}

And the Serilog appsetings.json section for generating one file daily will look like:

  "Serilog": {
    "MinimumLevel": {
      "Default": "Information",
      "Override": {
        "Microsoft": "Warning",
        "System": "Warning"
      }
    },
    "Using": [ "Serilog.Sinks.Console", "Serilog.Sinks.File" ],
    "WriteTo": [
      {
        "Name": "File",
        "Args": {
          "path": "C:\\Logs\\Program.json",
          "rollingInterval": "Day",
          "formatter": "Serilog.Formatting.Compact.CompactJsonFormatter, Serilog.Formatting.Compact"
        }
      }
    ]
  }

Is it possible to set UIView border properties from interface builder?

Similar answer to iHulk's one, but in Swift

Add a file named UIView.swift in your project (or just paste this in any file) :

import UIKit

@IBDesignable extension UIView {
    @IBInspectable var borderColor: UIColor? {
        set {
            layer.borderColor = newValue?.cgColor
        }
        get {
            guard let color = layer.borderColor else {
                return nil
            }
            return UIColor(cgColor: color)
        }
    }
    @IBInspectable var borderWidth: CGFloat {
        set {
            layer.borderWidth = newValue
        }
        get {
            return layer.borderWidth
        }
    }
    @IBInspectable var cornerRadius: CGFloat {
        set {
            layer.cornerRadius = newValue
            clipsToBounds = newValue > 0
        }
        get {
            return layer.cornerRadius
        }
    }
}

Then this will be available in Interface Builder for every button, imageView, label, etc. in the Utilities Panel > Attributes Inspector :

Attributes Inspector

Note: the border will only appear at runtime.

What is CDATA in HTML?

CDATA is a sequence of characters from the document character set and may include character entities. User agents should interpret attribute values as follows: Replace character entities with characters,

Ignore line feeds,

Replace each carriage return or tab with a single space.