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Some Of The Best Answers From Latest Asked Questions

Trying to merge 2 dataframes but get ValueError

At first check the type of columns which you want to merge. You will see one of them is string where other one is int. Then convert it to int as following code:

df["something"] = df["something"].astype(int)

merged = df.merge[df1, on="something"]

react button onClick redirect page

With React Router v5.1:

import {useHistory} from 'react-router-dom';
import React, {Component} from 'react';
import {Button} from 'reactstrap';
.....
.....
export class yourComponent extends Component {
    .....
    componentDidMount() { 
        let history = useHistory;
        .......
    }

    render() {
        return(
        .....
        .....
            <Button className="fooBarClass" onClick={() => history.back()}>Back</Button>

        )
    }
}

WebDriverException: unknown error: DevToolsActivePort file doesn't exist while trying to initiate Chrome Browser

Update:

I am able to get through the issue and now I am able to access the chrome with desired url.

Results of trying the provided solutions:

I tried all the settings as provided above but I was unable to resolve the issue

Explanation regarding the issue:

As per my observation DevToolsActivePort file doesn't exist is caused when chrome is unable to find its reference in scoped_dirXXXXX folder.

Steps taken to solve the issue

  1. I have killed all the chrome processes and chrome driver processes.
  2. Added the below code to invoke the chrome

    System.setProperty("webdriver.chrome.driver","pathto\\chromedriver.exe");    
    ChromeOptions options = new ChromeOptions();
    options.setExperimentalOption("useAutomationExtension", false);
    WebDriver driver = new ChromeDriver(options);
    driver.get(url);
    

Using the above steps I was able to resolve the issue.

Thanks for your answers.

On npm install: Unhandled rejection Error: EACCES: permission denied

Try using this: On the command line, in your home directory, create a directory for global installations:

mkdir ~/.npm-global

Configure npm to use the new directory path:

npm config set prefix '~/.npm-global'

In your preferred text editor, open or create a ~/.profile file and add this line:

export PATH=~/.npm-global/bin:$PATH

On the command line, update your system variables:

source ~/.profile

Now use npm install it should work.

Dart/Flutter : Converting timestamp

I don't know if this will help anyone. The previous messages have helped me so I'm here to suggest a few things:

import 'package:intl/intl.dart';

    DateTime convertTimeStampToDateTime(int timeStamp) {
     var dateToTimeStamp = DateTime.fromMillisecondsSinceEpoch(timeStamp * 1000);
     return dateToTimeStamp;
   }

  String convertTimeStampToHumanDate(int timeStamp) {
    var dateToTimeStamp = DateTime.fromMillisecondsSinceEpoch(timeStamp * 1000);
    return DateFormat('dd/MM/yyyy').format(dateToTimeStamp);
  }

   String convertTimeStampToHumanHour(int timeStamp) {
     var dateToTimeStamp = DateTime.fromMillisecondsSinceEpoch(timeStamp * 1000);
     return DateFormat('HH:mm').format(dateToTimeStamp);
   }

   int constructDateAndHourRdvToTimeStamp(DateTime dateTime, TimeOfDay time ) {
     final constructDateTimeRdv = dateTimeToTimeStamp(DateTime(dateTime.year, dateTime.month, dateTime.day, time.hour, time.minute)) ;
     return constructDateTimeRdv;
   }

How to install OpenSSL in windows 10?

I recently needed to document how to get a version of it installed, so I've copied my steps here, as the other answers were using different sources from what I recommend, which is Cygwin. I like Cygwin because it is well maintained and provides a wealth of other utilities for Windows. Cygwin also allows you to easily update the versions as needed when vulnerabilities are fixed. Please update your version of OpenSSL often!

Open a Windows Command prompt and check to see if you have OpenSSL installed by entering: openssl version

If you get an error message that the command is NOT recognized, then install OpenSSL by referring to Cygwin following the summary steps below:

Basically, download and run the Cygwin Windows Setup App to install and to update as needed the OpenSSL application:

  1. Select an install directory, such as C:\cygwin64. Choose a download mirror such as: http://mirror.cs.vt.edu
  2. Enter in openssl into the search and select it. You can also select/un-select other items of interest at this time. The click Next twice then click Finish.
  3. After installing, you need to edit the PATH variable. On Windows, you can access the System Control Center by pressing Windows Key + Pause. In the System window, click Advanced System Settings ? Advanced (tab) ? Environment Variables. For Windows 10, a quick access is to enter "Edit the system environment variables" in the Start Search of Windows and click the button "Environment Variables". Change the PATH variable (double-click on it or Select and Edit), and add the path where your Cywgwin is, e.g. C:\cygwin\bin.
  4. Verify you have it installed via a new Command Prompt window: openssl version. For example: C:\Program Files\mosquitto>openssl versionOpenSSL 1.1.1f 31 Mar 2020

Which TensorFlow and CUDA version combinations are compatible?

I had a similar problem after upgrading to TF 2.0. The CUDA version that TF was reporting did not match what Ubuntu 18.04 thought I had installed. It said I was using CUDA 7.5.0, but apt thought I had the right version installed.

What I eventually had to do was grep recursively in /usr/local for CUDNN_MAJOR, and I found that /usr/local/cuda-10.0/targets/x86_64-linux/include/cudnn.h did indeed specify the version as 7.5.0.
/usr/local/cuda-10.1 got it right, and /usr/local/cuda pointed to /usr/local/cuda-10.1, so it was (and remains) a mystery to me why TF was looking at /usr/local/cuda-10.0.

Anyway, I just moved /usr/local/cuda-10.0 to /usr/local/old-cuda-10.0 so TF couldn't find it any more and everything then worked like a charm.

It was all very frustrating, and I still feel like I just did a random hack. But it worked :) and perhaps this will help someone with a similar issue.

Elasticsearch error: cluster_block_exception [FORBIDDEN/12/index read-only / allow delete (api)], flood stage disk watermark exceeded

Only changing the settings with the following command did not work in my environment:

curl -XPUT -H "Content-Type: application/json" http://localhost:9200/_all/_settings -d '{"index.blocks.read_only_allow_delete": null}'

I had to also ran the Force Merge API command:

curl -X POST "localhost:9200/my-index-000001/_forcemerge?pretty"

ref: Force Merge API

Difference between npx and npm?

Simple Definition:

npm - Javascript package manager

npx - Execute npm package binaries

Failed to resolve: com.google.firebase:firebase-core:16.0.1

Go to

Settings -> Android SDK -> SDK Tools ->

and make sure you install Google Play Services

com.google.android.gms:play-services-measurement-base is being requested by various other libraries

Add to list of your dependencies. Now need to have it for proper work of all firebase dependencies:

implementation 'com.google.firebase:firebase-core:16.0.1'

Authentication plugin 'caching_sha2_password' is not supported

Modify Mysql encryption

ALTER USER 'lcherukuri'@'localhost' IDENTIFIED WITH mysql_native_password BY 'password';

How do I center text vertically and horizontally in Flutter?

maybe u want to provide the same width and height for 2 container

Container(
            width: size.width * 0.30, height: size.height * 0.4,
            alignment: Alignment.center,
            decoration: BoxDecoration(
              borderRadius: BorderRadius.circular(6)
            ),
            child: Center(
              child: Text(categoryName, textAlign: TextAlign.center, style: TextStyle(
                fontWeight: FontWeight.bold,
                fontSize: 17,
                color: Colors.white,
              ),),
            ),

Flutter Circle Design

Try This!

demo

I have added 5 circles you can add more. And instead of RaisedButton use InkResponse.

import 'package:flutter/material.dart';

void main() {
  runApp(new MaterialApp(home: new ExampleWidget()));
}

class ExampleWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    Widget bigCircle = new Container(
      width: 300.0,
      height: 300.0,
      decoration: new BoxDecoration(
        color: Colors.orange,
        shape: BoxShape.circle,
      ),
    );

    return new Material(
      color: Colors.black,
      child: new Center(
        child: new Stack(
          children: <Widget>[
            bigCircle,
            new Positioned(
              child: new CircleButton(onTap: () => print("Cool"), iconData: Icons.favorite_border),
              top: 10.0,
              left: 130.0,
            ),
            new Positioned(
              child: new CircleButton(onTap: () => print("Cool"), iconData: Icons.timer),
              top: 120.0,
              left: 10.0,
            ),
            new Positioned(
              child: new CircleButton(onTap: () => print("Cool"), iconData: Icons.place),
              top: 120.0,
              right: 10.0,
            ),
            new Positioned(
              child: new CircleButton(onTap: () => print("Cool"), iconData: Icons.local_pizza),
              top: 240.0,
              left: 130.0,
            ),
            new Positioned(
              child: new CircleButton(onTap: () => print("Cool"), iconData: Icons.satellite),
              top: 120.0,
              left: 130.0,
            ),
          ],
        ),
      ),
    );
  }
}

class CircleButton extends StatelessWidget {
  final GestureTapCallback onTap;
  final IconData iconData;

  const CircleButton({Key key, this.onTap, this.iconData}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    double size = 50.0;

    return new InkResponse(
      onTap: onTap,
      child: new Container(
        width: size,
        height: size,
        decoration: new BoxDecoration(
          color: Colors.white,
          shape: BoxShape.circle,
        ),
        child: new Icon(
          iconData,
          color: Colors.black,
        ),
      ),
    );
  }
}

Python Pandas User Warning: Sorting because non-concatenation axis is not aligned

jezrael's answer is good, but did not answer a question I had: Will getting the "sort" flag wrong mess up my data in any way? The answer is apparently "no", you are fine either way.

from pandas import DataFrame, concat

a = DataFrame([{'a':1,      'c':2,'d':3      }])
b = DataFrame([{'a':4,'b':5,      'd':6,'e':7}])

>>> concat([a,b],sort=False)
   a    c  d    b    e
0  1  2.0  3  NaN  NaN
0  4  NaN  6  5.0  7.0

>>> concat([a,b],sort=True)
   a    b    c  d    e
0  1  NaN  2.0  3  NaN
0  4  5.0  NaN  6  7.0

How to make audio autoplay on chrome

I add controls attribute too tag audio, and simply hide it in CSS. And all works fine in Chrome.

<audio autoplay loop controls id="playAudio">
  <source src="audio/source.mp3">
</audio>

java.lang.NoClassDefFoundError:failed resolution of :Lorg/apache/http/ProtocolVersion

This Might be Late Answer. but, I hope its save someone time:

If you are using com.google.android.gms:play-services-maps:16.0.0 or below and your app is targeting API level 28 (Android 9.0) or above, you must include the following declaration within the element of AndroidManifest.xml

<application
        ...
        ...
        android:usesCleartextTraffic="true"
        android:requestLegacyExternalStorage="true">

       <uses-library
            android:name="org.apache.http.legacy"
            android:required="false" />

</application>

Note: android:requestLegacyExternalStorage="true" required for Android 10+ to access storage R/W

Android 6.0 introduced the useCleartextTraffic attribute under application element in android manifest. The default value in Android P is “false”. Setting this to true indicates that the app intends to use clear network traffic.

If your app opts out of scoped storage when running on Android 10 devices, it's recommended that you continue to set requestLegacyExternalStorage to true in your app's manifest file. That way, your app can continue to behave as expected on devices that run Android 10

How to do a timer in Angular 5

This may be overkill for what you're looking for, but there is an npm package called marky that you can use to do this. It gives you a couple of extra features beyond just starting and stopping a timer. You just need to install it via npm and then import the dependency anywhere you'd like to use it. Here is a link to the npm package: https://www.npmjs.com/package/marky

An example of use after installing via npm would be as follows:

import * as _M from 'marky';

@Component({
 selector: 'app-test',
 templateUrl: './test.component.html',
 styleUrls: ['./test.component.scss']
})

export class TestComponent implements OnInit {
 Marky = _M;
}

constructor() {}

ngOnInit() {}

startTimer(key: string) {
 this.Marky.mark(key);
}

stopTimer(key: string) {
 this.Marky.stop(key);
}

key is simply a string which you are establishing to identify that particular measurement of time. You can have multiple measures which you can go back and reference your timer stats using the keys you create.

Avoid "current URL string parser is deprecated" warning by setting useNewUrlParser to true

const mongoose = require('mongoose');

mongoose
  .connect(connection_string, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
    useCreateIndex: true,
    useFindAndModify: false,
  })
  .then((con) => {
    console.log("connected to db");
  });

try to use this

Iterating through a list to render multiple widgets in Flutter?

Basically when you hit 'return' on a function the function will stop and will not continue your iteration, so what you need to do is put it all on a list and then add it as a children of a widget

you can do something like this:

  Widget getTextWidgets(List<String> strings)
  {
    List<Widget> list = new List<Widget>();
    for(var i = 0; i < strings.length; i++){
        list.add(new Text(strings[i]));
    }
    return new Row(children: list);
  }

or even better, you can use .map() operator and do something like this:

  Widget getTextWidgets(List<String> strings)
  {
    return new Row(children: strings.map((item) => new Text(item)).toList());
  }

Install Android App Bundle on device

You cannot install app bundle [NAME].aab directly to android device because it is publishing format, but there is way to extract the required apk from bundle and install it to you device, the process is as follow

  1. Download bundletool from here
  2. run this in your terminal,
java -jar bundletool.jar build-apks --bundle=bundleapp.aab --output=out_bundle_archive_set.apks
  1. Last step will generate a file named as out_bundle_archive_set.apks, just rename it to out_bundle_archive_set.zip and extract the zip file, jump into the folder out_bundle_archive_set > standalones, where you will seee a list of all the apks

There goes the reference from android developers for bundle tools link

android developer reference

Can not find module “@angular-devkit/build-angular”

Try to install angular-devkit for building angular projects

npm install --save-dev @angular-devkit/build-angular

How to change TextField's height and width?

If you want to increase the height of TextFormField dynamically while typing the text in it. Set maxLines to null. Like

TextFormField(
          onSaved: (newText) {
            enteredTextEmail = newText;
          },

          obscureText: false,
          keyboardType: TextInputType.emailAddress,
          validator: validateName,
          maxLines: null,
          // style: style,
          decoration: InputDecoration(
              contentPadding: EdgeInsets.fromLTRB(5.0, 10.0, 5.0, 10.0),
              hintText: "Enter Question",
              labelText: "Enter Question",
              border: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(10.0))),
        ),

How to resolve Unable to load authentication plugin 'caching_sha2_password' issue

This could be your connectors for MySQL which need to be updated, as MySQL8 changed the encryption of passwords - so older connectors are encrypting them incorrectly.

The maven repo for the java connector can be found here.
If you use flyway plugin, you should also consider updating it, too!

Then you can simply update your maven pom with:

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.17</version>
</dependency>

Or for others who use Gradle, you can update build.gradle with:

 buildscript {
    ext {
        ...
    }
    repositories {
        ...
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
        classpath('mysql:mysql-connector-java:8.0.11')
    }
 }

All that you really need to do (build.gradle example)

Connection Java-MySql : Public Key Retrieval is not allowed

First of all, please make sure your Database server is up and running. I was getting the same error, after trying all the answers listed here I found out that my Database server was not running.

You can check the same from MySQL Workbench, or Command line using

mysql -u USERNAME -p

This sounds obvious, but many times we assume that Database server is up and running all the time, especially when we are working on our local machine, when we restart/shutdown the machine, Database server will be shutdown automatically.

destination path already exists and is not an empty directory

This error comes up when you try to clone a repository in a folder which still contains .git folder (Hidden folder).

If the earlier answers doesn't work then you can proceed with my answer. Hope it will solve your issue.

Open terminal & change the directory to the destination folder (where you want to clone).

Now type: ls -a

You may see a folder named .git.

You have to remove that folder by the following command: rm -rf .git

Now you are ready to clone your project.

Local package.json exists, but node_modules missing

Just had the same error message, but when I was running a package.json with:

"scripts": {
    "build": "tsc -p ./src",
}

tsc is the command to run the TypeScript compiler.

I never had any issues with this project because I had TypeScript installed as a global module. As this project didn't include TypeScript as a dev dependency (and expected it to be installed as global), I had the error when testing in another machine (without TypeScript) and running npm install didn't fix the problem. So I had to include TypeScript as a dev dependency (npm install typescript --save-dev) to solve the problem.

Could not find module "@angular-devkit/build-angular"

I am facing the same issue since 2 days.

ng -v :6.0.8
node -v :8.11.2
npm -v :6.1.0

Make sure you are in the folder where angular.json is installed. Get into that and type ng serve. If the issue still arises, then you are having only dependencies installed in node_modules. Type the following, and it will work:

npm i --only=dev

How to remove package using Angular CLI?

npm uninstal @angular/material

and also clear file custom-theme.scss

Conda version pip install -r requirements.txt --target ./lib

would this work?

cat requirements.txt | while read x; do conda install "$x" -p ./lib ;done

or

conda install --file requirements.txt -p ./lib

Flask at first run: Do not use the development server in a production environment

Unless you tell the development server that it's running in development mode, it will assume you're using it in production and warn you not to. The development server is not intended for use in production. It is not designed to be particularly efficient, stable, or secure.

Enable development mode by setting the FLASK_ENV environment variable to development.

$ export FLASK_APP=example
$ export FLASK_ENV=development
$ flask run

If you're running in PyCharm (or probably any other IDE) you can set environment variables in the run configuration.

Development mode enables the debugger and reloader by default. If you don't want these, pass --no-debugger or --no-reloader to the run command.


That warning is just a warning though, it's not an error preventing your app from running. If your app isn't working, there's something else wrong with your code.

Enable CORS in fetch api

Browser have cross domain security at client side which verify that server allowed to fetch data from your domain. If Access-Control-Allow-Origin not available in response header, browser disallow to use response in your JavaScript code and throw exception at network level. You need to configure cors at your server side.

You can fetch request using mode: 'cors'. In this situation browser will not throw execption for cross domain, but browser will not give response in your javascript function.

So in both condition you need to configure cors in your server or you need to use custom proxy server.

Select default option value from typescript angular 6

In my case I'm using the same markup for editing an existing entity, or creating a brand new one (so far anyway).

I want to display a default-value that is "selected" in the select-elements when in creationMode, while displaying the values form the backend in editMode.

My solution is:

<select [(ngModel)]="entity.property" id="property" name="property" required>
  <option disabled hidden value="undefined">Enter prop</option>
  <option *ngFor="let prop of sortedProps" value="{{prop.value}}">{{prop.displayName}}</option>
</select>

for the regular available options I'm using a sortedProps Array to provide option choices. But that's not the important part here.

What did the trick for me is setting value="undefined" to let the angular-model-binding (?) select this option automatically when in creationMode. Not sure if its a hack, but does exactly what i want. No addtionally typeScript necessary.

Additionally, sepcifing hidden makes sure the option in my case is not selectable, while required makes sure the form is invalid unless something gets selected there.

TypeError: only integer scalar arrays can be converted to a scalar index with 1D numpy indices array

A simple case that generates this error message:

In [8]: [1,2,3,4,5][np.array([1])]
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-8-55def8e1923d> in <module>()
----> 1 [1,2,3,4,5][np.array([1])]

TypeError: only integer scalar arrays can be converted to a scalar index

Some variations that work:

In [9]: [1,2,3,4,5][np.array(1)]     # this is a 0d array index
Out[9]: 2
In [10]: [1,2,3,4,5][np.array([1]).item()]    
Out[10]: 2
In [11]: np.array([1,2,3,4,5])[np.array([1])]
Out[11]: array([2])

Basic python list indexing is more restrictive than numpy's:

In [12]: [1,2,3,4,5][[1]]
....
TypeError: list indices must be integers or slices, not list

edit

Looking again at

indices = np.random.choice(range(len(X_train)), replace=False, size=50000, p=train_probs)

indices is a 1d array of integers - but it certainly isn't scalar. It's an array of 50000 integers. List's cannot be indexed with multiple indices at once, regardless of whether they are in a list or array.

What is the difference between Jupyter Notebook and JupyterLab?

Jupyter Notebook is a web-based interactive computational environment for creating Jupyter notebook documents. It supports several languages like Python (IPython), Julia, R etc. and is largely used for data analysis, data visualization and further interactive, exploratory computing.

JupyterLab is the next-generation user interface including notebooks. It has a modular structure, where you can open several notebooks or files (e.g. HTML, Text, Markdowns etc) as tabs in the same window. It offers more of an IDE-like experience.

For a beginner I would suggest starting with Jupyter Notebook as it just consists of a filebrowser and an (notebook) editor view. It might be easier to use. If you want more features, switch to JupyterLab. JupyterLab offers much more features and an enhanced interface, which can be extended through extensions: JupyterLab Extensions (GitHub)

Vue.js get selected option on @change

The changed value will be in event.target.value

_x000D_
_x000D_
const app = new Vue({_x000D_
  el: "#app",_x000D_
  data: function() {_x000D_
    return {_x000D_
      message: "Vue"_x000D_
    }_x000D_
  },_x000D_
  methods: {_x000D_
    onChange(event) {_x000D_
      console.log(event.target.value);_x000D_
    }_x000D_
  }_x000D_
})
_x000D_
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/vue.js"></script>_x000D_
<div id="app">_x000D_
  <select name="LeaveType" @change="onChange" class="form-control">_x000D_
   <option value="1">Annual Leave/ Off-Day</option>_x000D_
   <option value="2">On Demand Leave</option>_x000D_
</select>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Google Maps shows "For development purposes only"

It seems to me that when it displays the "For development purposes only", one cannot see the map configurations as well while developing(or rather playing around with the configurations). In my case I have not enabled billing to be associated with the API I am using and I am thinking that's the reason why its behaving this way.

Axios having CORS issue

CORS issue can be simply resolved by following this:

Create a new shortcut of Google Chrome(update browser installation path accordingly) with following value:

"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --disable-web-security --user-data-dir="D:\chrome\temp"

How to add image in Flutter

their is no need to create asset directory and under it images directory and then you put image. Better is to just create Images directory inside your project where pubspec.yaml exist and put images inside it and access that images just like as shown in tutorial/documention

assets: - images/lake.jpg // inside pubspec.yaml

Bootstrap 4 multiselect dropdown

Because the bootstrap-select is a bootstrap component and therefore you need to include it in your code as you did for your V3

NOTE: this component only works in since version 1.13.0

_x000D_
_x000D_
$('select').selectpicker();
_x000D_
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css">_x000D_
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-select/1.13.1/css/bootstrap-select.css" />_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.bundle.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-select/1.13.1/js/bootstrap-select.min.js"></script>_x000D_
_x000D_
_x000D_
_x000D_
<select class="selectpicker" multiple data-live-search="true">_x000D_
  <option>Mustard</option>_x000D_
  <option>Ketchup</option>_x000D_
  <option>Relish</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

Cross-Origin Read Blocking (CORB)

You have to add CORS on the server side:

If you are using nodeJS then:

First you need to install cors by using below command :

npm install cors --save

Now add the following code to your app starting file like ( app.js or server.js)

var express = require('express');
var app = express();

var cors = require('cors');
var bodyParser = require('body-parser');

//enables cors
app.use(cors({
  'allowedHeaders': ['sessionId', 'Content-Type'],
  'exposedHeaders': ['sessionId'],
  'origin': '*',
  'methods': 'GET,HEAD,PUT,PATCH,POST,DELETE',
  'preflightContinue': false
}));

require('./router/index')(app);

How to print environment variables to the console in PowerShell?

Prefix the variable name with env:

$env:path

For example, if you want to print the value of environment value "MINISHIFT_USERNAME", then command will be:

$env:MINISHIFT_USERNAME

You can also enumerate all variables via the env drive:

Get-ChildItem env:

How to uninstall Eclipse?

There is no automated uninstaller.

You have to remove Eclipse manually. At least Eclipse does not write anything in the system registry, so deleting some directories and files is enough.

Note: I use Unix style paths in this answer but the locations should be the same on Windows or Unix systems, so ~ refers to the user home directory even on Windows.

Why is there no uninstaller?

According to this discussion about uninstalling Eclipse, the reasoning for not providing an uninstaller is that the Eclipse installer is supposed to just automate a few tasks that in the past had to be done manually (like downloading and extracting Eclipse and adding shortcuts), so they also can be undone manually. There is no entry in "Programs and Features" because the installer does not register anything in the system registry.

How to quickly uninstall Eclipse

Just delete the Eclipse directory and any desktop and start menu shortcuts and be done with it, if you don't mind a few leftover files.

In my opinion this is generally enough and I would stop here, because multiple Eclipse installations can share some files and you don't accidentally want to delete those shared files. You also keep all your projects.

How to completely uninstall Eclipse

If you really want to remove Eclipse without leaving any traces, you have to manually delete

  • all desktop and start menu shortcuts
  • the installation directory (e.g. ~/eclipse/photon/)
  • the p2 bundle pool (which is often shared with other eclipse installations)

The installer has a "Bundle Pools" menu entry which lists the locations of all bundle pools. If you have other Eclipse installations on your system you can use the "Cleanup Agent" to clean up unused bundles. If you don't have any other Eclipse installations you can delete the whole bundle pool directory instead (by default ~/p2/).

If you want to completely remove the Eclipse installer too, delete the installer's executable and the ~/.eclipse/ directory.

Depending on what kind of work you did with Eclipse, there can be more directories that you may want to delete. If you used Maven, then ~/.m2/ contains the Maven cache and settings (shared with Maven CLI and other IDEs). If you develop Eclipse plugins, then there might be JUnit workspaces from test runs, next to you Eclipse workspace. Likewise other build tools and development environments used in Eclipse could have created similar directories.

How to delete all projects

If you want to delete your projects and workspace metadata, you have to delete your workspace(s). The default workspace location is ´~/workspace/´. You can also search for the .metadata directory to get all Eclipse workspaces on your machine.

If you are working with Git projects, these are generally not saved in the workspace but in the ~/git/ directory.

curl: (35) error:1408F10B:SSL routines:ssl3_get_record:wrong version number

If anyone is getting this error using Nginx, try adding the following to your server config:

server {
    listen 443 ssl;
    ...
}

The issue stems from Nginx serving an HTTP server to a client expecting HTTPS on whatever port you're listening on. When you specify ssl in the listen directive, you clear this up on the server side.

Using Environment Variables with Vue.js

Important (in Vue 4 and likely Vue 3+ as well!): I set VUE_APP_VAR but could NOT see it by console logging process and opening the env object. I could see it by logging or referencing process.env.VUE_APP_VAR. I'm not sure why this is but be aware that you have to access the variable directly!

Flutter position stack widget in center

The Best way worked for me, was using Align. I needed to make the profile picture of a user in the bottom center of the Cover picture.

return Container(
  height: 220,
  color: Colors.red,
  child: Stack(
    children: [
      Container(
        height: 160,
        color: Colors.yellow,
      ),
      Align(
        alignment: Alignment.bottomCenter,
        child: UserProfileImage(),
      ),
    ],
  ),
);

This worked like a charm.

Could not install packages due to a "Environment error :[error 13]: permission denied : 'usr/local/bin/f2py'"

I too had to face the same problem. This worked for me. Right click and run as admin than run usual command to install. But first run update command to update the pip

python -m pip install --upgrade pip

Angular 6: How to set response type as text while making http call

By Default angular return responseType as Json, but we can configure below types according to your requirement.

responseType: 'arraybuffer'|'blob'|'json'|'text'

Ex:

this.http.post(
    'http://localhost:8080/order/addtocart', 
    { dealerId: 13, createdBy: "-1", productId, quantity }, 
    { headers, responseType: 'text'});

Android design support library for API 28 (P) not working

I've used that option:

With Android Studio 3.2 and higher, you can quickly migrate an existing project to use AndroidX by selecting Refactor > Migrate to AndroidX from the menu bar.

https://developer.android.com/jetpack/androidx/migrate

How to center a component in Material-UI and make it responsive?

You can do this with the Box component:

import Box from "@material-ui/core/Box";

...

<Box
  display="flex"
  justifyContent="center"
  alignItems="center"
  minHeight="100vh"
>
  <YourComponent/>
</Box>

E: gnupg, gnupg2 and gnupg1 do not seem to be installed, but one of them is required for this operation

In addition to existing answers:

RUN apt-get update && apt-get install -y gnupg

-y flag agrees to terms during installation process. It is important not to break the build

Custom Card Shape Flutter SDK

When Card I always use RoundedRectangleBorder.

Card(
  color: Colors.grey[900],
  shape: RoundedRectangleBorder(
    side: BorderSide(color: Colors.white70, width: 1),
    borderRadius: BorderRadius.circular(10),
  ),
  margin: EdgeInsets.all(20.0),
  child: Container(
    child: Column(
        children: <Widget>[
        ListTile(
            title: Text(
            'example',
            style: TextStyle(fontSize: 18, color: Colors.white),
            ),
        ),
        ],
    ),
  ),
),

What exactly is the 'react-scripts start' command?

As Sagiv b.g. pointed out, the npm start command is a shortcut for npm run start. I just wanted to add a real-life example to clarify it a bit more.

The setup below comes from the create-react-app github repo. The package.json defines a bunch of scripts which define the actual flow.

"scripts": {
  "start": "npm-run-all -p watch-css start-js",
  "build": "npm run build-css && react-scripts build",
  "watch-css": "npm run build-css && node-sass-chokidar --include-path ./src --include-path ./node_modules src/ -o src/ --watch --recursive",
  "build-css": "node-sass-chokidar --include-path ./src --include-path ./node_modules src/ -o src/",
  "start-js": "react-scripts start"
},

For clarity, I added a diagram. enter image description here

The blue boxes are references to scripts, all of which you could executed directly with an npm run <script-name> command. But as you can see, actually there are only 2 practical flows:

  • npm run start
  • npm run build

The grey boxes are commands which can be executed from the command line.

So, for instance, if you run npm start (or npm run start) that actually translate to the npm-run-all -p watch-css start-js command, which is executed from the commandline.

In my case, I have this special npm-run-all command, which is a popular plugin that searches for scripts that start with "build:", and executes all of those. I actually don't have any that match that pattern. But it can also be used to run multiple commands in parallel, which it does here, using the -p <command1> <command2> switch. So, here it executes 2 scripts, i.e. watch-css and start-js. (Those last mentioned scripts are watchers which monitor file changes, and will only finish when killed.)

  • The watch-css makes sure that the *.scss files are translated to *.cssfiles, and looks for future updates.

  • The start-js points to the react-scripts start which hosts the website in a development mode.

In conclusion, the npm start command is configurable. If you want to know what it does, then you have to check the package.json file. (and you may want to make a little diagram when things get complicated).

Xcode 10 Error: Multiple commands produce

My error was:

duplicate output file

'/Users/home/Library/Developer/Xcode/DerivedData/myAppName-fawptgabysjowicvpeqydjniuovo/Build/Products/Debug-iphoneos/myAppName.app/GoogleMaps.bundle' on task: PhaseScriptExecution [CP] Copy Pods Resources /Users/home/Library/Developer/Xcode/DerivedData/myAppName-fawptgabysjowicvpeqydjniuovo/Build/Intermediates.noindex/myAppName.build/Debug-iphoneos/myAppName.build/Script-32CCC25BF727B592A1784900.sh

I focused on the problem file being GoogleMaps.bundle and the location of that file being in [CP] Copy Pods Resources, and the fact that it specified it’s a duplicate output file (I highlighted them in black above), it's the 4th step below

Make sure you do the following steps on a Duplicate Project

1- In the project navigator I went to the blue project icon

enter image description here

2- I choose Build phases

enter image description here

3- Under Build Phases I choose [CP] Copy Pods Resources

enter image description here

4- Under [CP] Copy Pods Resources I went to Output Files and underneath there I found the file that ended with GoogleMaps.bundle. I selected it and pressed the minus sign to delete it. Make sure you go to Output Files and NOT Input Files

enter image description here

5- I did a clean shift+cmmd+k and afterwards when I built the project the error was gone

The odd thing was even though the red error went away the yellow warning was still there but it worked :)

how to download file in react js

React gives a security issue when using a tag with target="_blank".

I managed to get it working like that:

<a href={uploadedFileLink} target="_blank" rel="noopener noreferrer" download>
   <Button>
      <i className="fas fa-download"/>
      Download File
   </Button>
</a>

phpMyAdmin - Error > Incorrect format parameter?

Without any problems, I imported directly from the command line.

mysql -uroot -hURLServer -p DBName< filename.sql

How do I resolve a TesseractNotFoundError?

I was also facing the same issue, just add C:\Program Files (x86)\Tesseract-OCR to your path variable. If it still does not work, add C:\Program Files (x86)\Tesseract-OCR\tessdata to your path variable in a new line. And do not forget to restart your computer after adding the path variable.

Flutter command not found

My solution was to open the bash file in the terminal.

  1. Go to Terminal
  2. go to the top level dir
  3. type: open bash
  4. Another Terminal will open
  5. Now type "flutter" in the new terminal and it will function.

Set default option in mat-select

Using Form Model (Reactive Forms)

--- Html code--
<form [formGroup]="patientCategory">
<mat-form-field class="full-width">
    <mat-select placeholder="Category" formControlName="patientCategory">
        <mat-option>--</mat-option>
        <mat-option *ngFor="let category of patientCategories" [value]="category">
            {{category.name}} 
        </mat-option>
    </mat-select>
</mat-form-field>

----ts code ---

ngOnInit() {

        this.patientCategory = this.fb.group({
            patientCategory: [null, Validators.required]
        });

      const toSelect = "Your Default Value";
      this.patientCategory.get('patientCategory').setValue(toSelect);
    }

With out form Model

--- html code --
<mat-form-field>
  <mat-label>Select an option</mat-label>
  <mat-select [(value)]="selected">
    <mat-option>None</mat-option>
    <mat-option value="option1">Option 1</mat-option>
    <mat-option value="option2">Option 2</mat-option>
    <mat-option value="option3">Option 3</mat-option>
  </mat-select>
</mat-form-field>

---- ts code -- selected = 'option1'; Here take care about type of the value assigning

standard_init_linux.go:190: exec user process caused "no such file or directory" - Docker

It's a CRLF problem. I fixed the problem using this:

git config --global core.eol lf

git config --global core.autocrlf input

find . -type f -print0 | xargs -0 dos2unix

Google Recaptcha v3 example demo

I process POST on PHP from an angular ajax call. I also like to see the SCORE from google.

This works well for me...

$postData = json_decode(file_get_contents('php://input'), true); //get data sent via post
$captcha = $postData['g-recaptcha-response'];

header('Content-Type: application/json');
if($captcha === ''){
    //Do something with error
    echo '{ "status" : "bad", "score" : "none"}';
} else {
    $secret   = 'your-secret-key';
    $response = file_get_contents(
        "https://www.google.com/recaptcha/api/siteverify?secret=" . $secret . "&response=" . $captcha . "&remoteip=" . $_SERVER['REMOTE_ADDR']
    );
    // use json_decode to extract json response
    $response = json_decode($response);

    if ($response->success === false) {
        //Do something with error
        echo '{ "status" : "bad", "score" : "none"}';
    }else if ($response->success==true && $response->score <= 0.5) {
        echo '{ "status" : "bad", "score" : "'.$response->score.'"}';
    }else {
        echo '{ "status" : "ok", "score" : "'.$response->score.'"}';
    }
}

On HTML

<input type="hidden" id="g-recaptcha-response" name="g-recaptcha-response">

On js

$scope.grabCaptchaV3=function(){
    var params = {
                     method: 'POST',
                     url: 'api/recaptcha.php',
                     headers: {
                       'Content-Type': undefined
                     },
                     data:   {'g-recaptcha-response' : myCaptcha }
     }
     $http(params).then(function(result){ 
                console.log(result.data);
     }, function(response){
                console.log(response.statusText);
     }); 
}

How to use mouseover and mouseout in Angular 6

Adding to what was already said.

if you want to *ngFor an element , and hide \ show elements in it, on hover, like you added in the comments, you should re-think the whole concept.

a more appropriate way to do it, does not involve angular at all. I would go with pure CSS instead, using its native :hover property.

something like:

App.Component.css

div span.only-show-on-hover {
    visibility: hidden;
}
div:hover span.only-show-on-hover  {
    visibility: visible;
}

App.Component.html

  <div *ngFor="let i of [1,2,3,4]" > hover me please.
    <span class="only-show-on-hover">you only see me when hovering</span>
  </div>

added a demo: https://stackblitz.com/edit/hello-angular-6-hvgx7n?file=src%2Fapp%2Fapp.component.html

Error: JavaFX runtime components are missing, and are required to run this application with JDK 11

This worked for me:

File >> Project Structure >> Modules >> Dependency >> + (on left-side of window)

clicking the "+" sign will let you designate the directory where you have unpacked JavaFX's "lib" folder.

Scope is Compile (which is the default.) You can then edit this to call it JavaFX by double-clicking on the line.

then in:

Run >> Edit Configurations

Add this line to VM Options:

--module-path /path/to/JavaFX/lib --add-modules=javafx.controls

(oh and don't forget to set the SDK)

Failed to resolve: com.android.support:appcompat-v7:28.0

As @Sourabh already pointed out, you can check in the Google Maven link what are the packages that Google has listed out.

If you, like me, are prompted with a similar message to this Failed to resolve: com.android.support:appcompat-v7:28.0, it could be that you got there after upgrading the targetSdkVersion or compileSdkVersion.

What is basically happening is that the package is not being found, as the message correctly says. If you upgraded the SDK, check the Google Maven, to check what are the available versions of the package for the new SDK version that you want to upgrade to.

I had these dependencies (on version 27):

implementation 'com.android.support:appcompat-v7:27.1.1'
implementation 'com.android.support:design:27.1.1'
implementation 'com.android.support:recyclerview-v7:27.1.1'
implementation 'com.android.support:cardview-v7:27.1.1'
implementation 'com.android.support:support-v4:27.1.1'

And I had to change the SDK version and the rest of the package number:

implementation 'com.android.support:appcompat-v7:28.0.0'
implementation 'com.android.support:design:28.0.0'
implementation 'com.android.support:recyclerview-v7:28.0.0'
implementation 'com.android.support:cardview-v7:28.0.0'
implementation 'com.android.support:support-v4:28.0.0'

Now the packages are found and downloaded. Since the only available package for the 28 version of the SDK is 28.0.0 at the moment of writing this.

git clone: Authentication failed for <URL>

I'm facing exactly same error when I'm trying to clone a repository on a brand new machine. I'm using Git bash as my Git client. When I ran Git's command to clone a repository it was not prompting me for user id and password which will be used for authentication. It was a fresh machine where not a single credential was cached by Windows credential manager.

As a last resort, I manually added my credentials in credentials manager.

Go to > Control Panel\User Accounts\Credential Manager > Windows Credentials

Click Add a Windows credential link and then Supply the details as shown in the form below and you're done:

enter image description here

I had put the details as below:

Internet or network address: <gitRepoServerNameOrIPAddress>
User Name: MyCompanysDomainName\MyUserName
Password: MyPassword

Next time you run any Git command targeting a repository set up on above address this manually created credential will be used.

It is also important if you have a git command line you close it and reopen it for changes to be applied.

How can I add raw data body to an axios request?

How about using direct axios API?

axios({
  method: 'post',
  url: baseUrl + 'applications/' + appName + '/dataexport/plantypes' + plan,
  headers: {}, 
  data: {
    foo: 'bar', // This is the body part
  }
});

Source: axios api

How do I install the Nuget provider for PowerShell on a unconnected machine so I can install a nuget package from the PS command line?

I accepted trebleCode's answer, but I wanted to provide a bit more detail regarding the steps I took to install the nupkg of interest pswindowsupdate.2.0.0.4.nupkg on my unconnected Win 7 machine by way of following trebleCode's answer.

First: after digging around a bit, I think I found the MS docs that trebleCode refers to:

Bootstrap the NuGet provider and NuGet.exe

Install-PackageProvider

To continue, as trebleCode stated, I did the following

Install NuGet provider on my connected machine

On a connected machine (Win 10 machine), from the PS command line, I ran Install-PackageProvider -Name NuGet -RequiredVersion 2.8.5.201 -Force. The Nuget software was obtained from the 'Net and installed on my local connected machine.

After the install I found the NuGet provider software at C:\Program Files\PackageManagement\ProviderAssemblies (Note: the folder name \ProviderAssemblies as opposed to \ReferenceAssemblies was the one minor difference relative to trebleCode's answer.

The provider software is in a folder structure like this:

C:\Program Files\PackageManagement\ProviderAssemblies
   \NuGet
      \2.8.5.208
         \Microsoft.PackageManagement.NuGetProvider.dll

Install NuGet provider on my unconnected machine

I copied the \NuGet folder (and all its children) from the connected machine onto a thumb drive and copied it to C:\Program Files\PackageManagement\ProviderAssemblies on my unconnected (Win 7) machine

I started PS (v5) on my unconnected (Win 7) machine and ran Import-PackageProvider -Name NuGet -RequiredVersion 2.8.5.201 to import the provider to the current PowerShell session.

I ran Get-PackageProvider -ListAvailable and saw this (NuGet appears where it was not present before):

Name                     Version          DynamicOptions                                                                                                                                                                      
----                     -------          --------------                                                                                                                                                                      
msi                      3.0.0.0          AdditionalArguments                                                                                                                                                                 
msu                      3.0.0.0                                                                                                                                                                                              
NuGet                    2.8.5.208        Destination, ExcludeVersion, Scope, SkipDependencies, Headers, FilterOnTag, Contains, AllowPrereleaseVersions, ConfigFile, SkipValidate                                             
PowerShellGet            1.0.0.1          PackageManagementProvider, Type, Scope, AllowClobber, SkipPublisherCheck, InstallUpdate, NoPathUpdate, Filter, Tag, Includes, DscResource, RoleCapability, Command, PublishLocati...
Programs                 3.0.0.0          IncludeWindowsInstaller, IncludeSystemComponent

Create local repository on my unconnected machine

On unconnected (Win 7) machine, I created a folder to serve as my PS repository (say, c:\users\foo\Documents\PSRepository)

I registered the repo: Register-PSRepository -Name fooPsRepository -SourceLocation c:\users\foo\Documents\PSRepository -InstallationPolicy Trusted

Install the NuGet package

I obtained and copied the nupkg pswindowsupdate.2.0.0.4.nupkg to c:\users\foo\Documents\PSRepository on my unconnected Win7 machine

I learned the name of the module by executing Find-Module -Repository fooPsRepository

Version    Name                                Repository           Description                                                                                                                      
-------    ----                                ----------           -----------                                                                                                                      
2.0.0.4    PSWindowsUpdate                     fooPsRepository      This module contain functions to manage Windows Update Client.

I installed the module by executing Install-Module -Name pswindowsupdate

I verified the module installed by executing Get-Command –module PSWindowsUpdate

CommandType     Name                                               Version    Source                                                                                                                 
-----------     ----                                               -------    ------                                                                                                                 
Alias           Download-WindowsUpdate                             2.0.0.4    PSWindowsUpdate                                                                                                        
Alias           Get-WUInstall                                      2.0.0.4    PSWindowsUpdate                                                                                                        
Alias           Get-WUList                                         2.0.0.4    PSWindowsUpdate                                                                                                        
Alias           Hide-WindowsUpdate                                 2.0.0.4    PSWindowsUpdate                                                                                                        
Alias           Install-WindowsUpdate                              2.0.0.4    PSWindowsUpdate                                                                                                        
Alias           Show-WindowsUpdate                                 2.0.0.4    PSWindowsUpdate                                                                                                        
Alias           UnHide-WindowsUpdate                               2.0.0.4    PSWindowsUpdate                                                                                                        
Alias           Uninstall-WindowsUpdate                            2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Add-WUServiceManager                               2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Enable-WURemoting                                  2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WindowsUpdate                                  2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WUApiVersion                                   2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WUHistory                                      2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WUInstallerStatus                              2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WUJob                                          2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WULastResults                                  2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WURebootStatus                                 2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WUServiceManager                               2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WUSettings                                     2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Get-WUTest                                         2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Invoke-WUJob                                       2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Remove-WindowsUpdate                               2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Remove-WUServiceManager                            2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Set-WUSettings                                     2.0.0.4    PSWindowsUpdate                                                                                                        
Cmdlet          Update-WUModule                                    2.0.0.4    PSWindowsUpdate 

I think I'm good to go

Xcode couldn't find any provisioning profiles matching

I opened XCode -> Preferences -> Accounts and clicked on Download certificate. That fixed my problem

Couldn't process file resx due to its being in the Internet or Restricted zone or having the mark of the web on the file

Complementing @lasse-v-karlsen answer. To unblock all files recursively, run from powershell as administrator inside the folder you want:

gci -recurse | Unblock-File

source link: How to Unblock Files Downloaded from Internet? - Winhelponline
https://www.winhelponline.com/blog/bulk-unblock-files-downloaded-internet/

How do I install Python packages in Google's Colab?

You can use !setup.py install to do that.

Colab is just like a Jupyter notebook. Therefore, we can use the ! operator here to install any package in Colab. What ! actually does is, it tells the notebook cell that this line is not a Python code, its a command line script. So, to run any command line script in Colab, just add a ! preceding the line.

For example: !pip install tensorflow. This will treat that line (here pip install tensorflow) as a command prompt line and not some Python code. However, if you do this without adding the ! preceding the line, it'll throw up an error saying "invalid syntax".

But keep in mind that you'll have to upload the setup.py file to your drive before doing this (preferably into the same folder where your notebook is).

Hope this answers your question :)

How do I use TensorFlow GPU?

I tried following the above tutorial. Thing is tensorflow changes a lot and so do the NVIDIA versions needed for running on a GPU. The next issue is that your driver version determines your toolkit version etc. As of today this information about the software requirements should shed some light on how they interplay:

NVIDIA® GPU drivers —CUDA 9.0 requires 384.x or higher.
CUDA® Toolkit —TensorFlow supports CUDA 9.0.
CUPTI ships with the CUDA Toolkit.
cuDNN SDK (>= 7.2) Note: Make sure your GPU has compute compatibility >3.0
(Optional) NCCL 2.2 for multiple GPU support.
(Optional) TensorRT 4.0 to improve latency and throughput for inference on some models.

And here you'll find the up-to-date requirements stated by tensorflow (which will hopefully be updated by them on a regular basis).

get current date with 'yyyy-MM-dd' format in Angular 4

Try this:

   import * as moment from 'moment';

     ngOnInit() {
     this.date = moment().format("YYYY Do MMM");
                }

jwt check if token expired

This is the answer if someone want to know

if (Date.now() >= exp * 1000) {
  return false;
}

What is AndroidX?

I got to know about AndroidX from this Android Dev Summit video. The summarization is -

  1. No more support library: The android support library will be never maintained by Google under the support library namespace. So if you want to find fixes of a bug in support library you must have to migrate your project in AndroidX
  2. Better package management: For standardized and independent versioning.Because previous support library versioning was too confusing. It will release you the pain of “All com.android.support libraries must use the exact same version specification” message.
  3. Other God libraries have migrated to AndroidX: Google play services, Firebase, Mockito 2, etc are migrated to AndroidX.
  4. New libraries will be published using AndroidX artifact: All the libraries will be in the AndroidX namespace like Android Jetpack

How to upgrade Python version to 3.7?

On ubuntu you can add this PPA Repository and use it to install python 3.7: https://launchpad.net/~jonathonf/+archive/ubuntu/python-3.7

Or a different PPA that provides several Python versions is Deadsnakes: https://launchpad.net/~deadsnakes/+archive/ubuntu/ppa

See also here: https://askubuntu.com/questions/865554/how-do-i-install-python-3-6-using-apt-get (I know it says 3.6 in the url, but the deadsnakes ppa also contains 3.7 so you can use it for 3.7 just the same)

If you want "official" you'd have to install it from the sources from the site, get the code (which you already downloaded) and do this:

tar -xf Python-3.7.0.tar.xz
cd Python-3.7.0
./configure
make
sudo make install        <-- sudo is required.

This might take a while

How to resolve TypeError: can only concatenate str (not "int") to str

Use this:

print("Program for calculating sum")
numbers=[1, 2, 3, 4, 5, 6, 7, 8]
sum=0
for number in numbers:
    sum += number
print("Total Sum is: %d" %sum )

ADB.exe is obsolete and has serious performance problems

None of the top-voted answers worked for me, except when I unchecked "Use detected ADB location" as mentioned above by @???. Fortunately, in my case though, the message didn't show up, even when I turned it back on. In other words, the problem might be resolved by restarting "Use detected ADB location" :)

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured

Your problem is the dependency of spring batch spring-boot-starter-batch that has a spring-boot-starter-jdbc transitive maven dependency.

Spring Batch is a framework for building reliable and fault tolerance enterprise batch jobs. It supports many features like restarting a failed batch, recording the status of the batch execution and so on. In order to achieve that Spring Batch uses a database schema to store the status of the registered jobs, the auto-configuration already provides you the basic configuration of the required data source and it is this configuration that requires the relational database configuration.

To solve this you must include some database driver like mysql, h2, etc. to configure the url.

Update: Just for getting start you can configure your application.yml like below:

spring:
  datasource:
    driver-class-name: org.h2.Driver
    url: jdbc:h2:mem:localhost;DB_CLOSE_ON_EXIT=FALSE
    username: admin
    password:

and of course in your pom.xml include the h2 dirver like this:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
       ....
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
        </dependency>

....
    </dependencies>
...

</project>

The motivation, because you can not use mongo for this purpose, is that the usage of mongo is provided only for item readers and writers and not for managing the internal database of Spring Batch that is an internal schema, not a business schema. The query is plain SQL query and the internal abstraction relies on a relational database. It is necessary to have a database with ACID capability because every batch reads and writes a chunk of work and saves that information in order to restart the job. A NoSql solution is not suitable for this.

At the end you have configured a relational database in order to prepare Spring Batch for internal capability, the internal abstraction does not rely on mongo only on jdbc. Then mongo can be used but for the business side of the batch via item reader/writer.

I hope that this can help you to clear your doubts.

Unable to resolve dependency for ':app@debug/compileClasspath': Could not resolve

One possibility I have not seen mentioned. If the project you are importing uses android product flavors, you may have a mistake in your missingDimenstionStrategy.

In your :app build.gradle (the one code that is failing to resolve the dependency), ensure you have correctly set the specific flavor of the product that you are depending on. This allows all your later dependency code (e..g implementation, api, etc) to know which precise build it depends on

 defaultConfig {
        ...<snip unrelated>...

        // Ensure you specify the flavor you depend on!!
        // If dep has multiple flavor dimensions, you need to specify them all
        missingDimensionStrategy 'classpath', 'gms17'
    }

Sort Array of object by object field in Angular 6

Not tested but should work

 products.sort((a,b)=>a.title.rendered > b.title.rendered)

How to increase image size of pandas.DataFrame.plot in jupyter notebook?

If you want to make a change global to the whole notebook:

import matplotlib.pyplot as plt
%matplotlib inline
plt.rcParams["figure.figsize"] = [10, 5]

How to use `@ts-ignore` for a block

If you don't need typesafe, just bring block to a new separated file and change the extension to .js,.jsx

How do you change the value inside of a textfield flutter?

Here is a full example where the parent widget controls the children widget. The parent widget updates the children widgets (Text and TextField) with a counter.

To update the Text widget, all you do is pass in the String parameter. To update the TextField widget, you need to pass in a controller, and set the text in the controller.

main.dart:

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Demo',
      home: Home(),
    );
  }
}

class Home extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text('Update Text and TextField demo'),
        ),
        body: ParentWidget());
  }
}

class ParentWidget extends StatefulWidget {
  @override
  _ParentWidgetState createState() => _ParentWidgetState();
}

class _ParentWidgetState extends State<ParentWidget> {
  int _counter = 0;
  String _text = 'no taps yet';
  var _controller = TextEditingController(text: 'initial value');

  void _handleTap() {
    setState(() {
      _counter = _counter + 1;
      _text = 'number of taps: ' + _counter.toString();
      _controller.text  = 'number of taps: ' + _counter.toString();
    });
  }

  @override
  Widget build(BuildContext context) {
    return Container(
      child: Column(children: <Widget>[
        RaisedButton(
          onPressed: _handleTap,
          child: const Text('Tap me', style: TextStyle(fontSize: 20)),
        ),
        Text('$_text'),
        TextField(controller: _controller,),
      ]),
    );
  }
}

You don't have write permissions for the /Library/Ruby/Gems/2.3.0 directory. (mac user)

As @idleberg mentions, on Mac OS, it is best to install rbenv to avoid permissions errors when using manually installed ruby.

Installation

$ brew update
$ brew install rbenv

Add the following in .bashrc file:

eval "$(rbenv init -)"

Now, we can look at the list of ruby versions available for install

$ rbenv install -l

Install version 2.3.8 for example

$ rbenv install 2.3.8

Now we can use this ruby version globally

$ rbenv global 2.3.8

Finally run

$ rbenv rehash
$ which ruby
/Users/myuser/.rbenv/shims/ruby
$ ruby -v
ruby 2.3.7p456 (2018-03-28 revision 63024) [x86_64-darwin17]

Go for it

Now install bundler

$ gem install bundler

All done!

How can I install a previous version of Python 3 in macOS using homebrew?

Short Answer

To make a clean install of Python 3.6.5 use:

brew unlink python # ONLY if you have installed (with brew) another version of python 3
brew install --ignore-dependencies https://raw.githubusercontent.com/Homebrew/homebrew-core/f2a764ef944b1080be64bd88dca9a1d80130c558/Formula/python.rb

If you prefer to recover a previously installed version, then:

brew info python           # To see what you have previously installed
brew switch python 3.x.x_x # Ex. 3.6.5_1

Long Answer

There are two formulas for installing Python with Homebrew: python@2 and python.
The first is for Python 2 and the second for Python 3.

Note: You can find outdated answers on the web where it is mentioned python3 as the formula name for installing Python version 3. Now it's just python!

By default, with these formulas you can install the latest version of the corresponding major version of Python. So, you cannot directly install a minor version like 3.6.

Solution

With brew, you can install a package using the address of the formula, for example in a git repository.

brew install https://the/address/to/the/formula/FORMULA_NAME.rb

Or specifically for Python 3

brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/COMMIT_IDENTIFIER/Formula/python.rb

The address you must specify is the address to the last commit of the formula (python.rb) for the desired version. You can find the commint identifier by looking at the history for homebrew-core/Formula/python.rb

https://github.com/Homebrew/homebrew-core/commits/master/Formula/python.rb

Python > 3.6.5

In the link above you will not find a formula for a version of Python above 3.6.5. After the maintainers of that (official) repository released Python 3.7, they only submit updates to the recipe of Python 3.7.

As explained above, with homebrew you have only Python 2 (python@2) and Python 3 (python), there is no explicit formula for Python 3.6.

Although those minor updates are mostly irrelevant in most cases and for most users, I will search if someone has done an explicit formula for 3.6.

FirebaseInstanceIdService is deprecated

Kotlin allows for even simpler code than what's shown in other answers.

To get the new token whenever it's refreshed:

class MyFirebaseMessagingService: FirebaseMessagingService() {

    override fun onNewToken(token: String?) {
        Log.d("FMS_TOKEN", token)
    }
    ...
}

To get the token from anywhere at runtime:

FirebaseInstanceId.getInstance().instanceId.addOnSuccessListener {
    Log.d("FMS_TOKEN", it.token)
}

Uncaught SyntaxError: Unexpected end of JSON input at JSON.parse (<anonymous>)

You are calling:

JSON.parse(scatterSeries)

But when you defined scatterSeries, you said:

var scatterSeries = []; 

When you try to parse it as JSON it is converted to a string (""), which is empty, so you reach the end of the string before having any of the possible content of a JSON text.

scatterSeries is not JSON. Do not try to parse it as JSON.

data is not JSON either (getJSON will parse it as JSON automatically).

ch is JSON … but shouldn't be. You should just create a plain object in the first place:

var ch = {
    "name": "graphe1",
    "items": data.results[1]
};

scatterSeries.push(ch);

In short, for what you are doing, you shouldn't have JSON.parse anywhere in your code. The only place it should be is in the jQuery library itself.

Everytime I run gulp anything, I get a assertion error. - Task function must be specified

The problem is that you are using gulp 4 and the syntax in gulfile.js is of gulp 3. So either downgrade your gulp to 3.x.x or make use of gulp 4 syntaxes.

Syntax Gulp 3:

gulp.task('default', ['sass'], function() {....} );

Syntax Gulp 4:

gulp.task('default', gulp.series(sass), function() {....} );

You can read more about gulp and gulp tasks on: https://medium.com/@sudoanushil/how-to-write-gulp-tasks-ce1b1b7a7e81

Setting values of input fields with Angular 6

As an alternate you can use reactive forms. Here is an example: https://stackblitz.com/edit/angular-pqb2xx

Template

<form [formGroup]="mainForm" ng-submit="submitForm()">
  Global Price: <input type="number" formControlName="globalPrice">
  <button type="button" [disabled]="mainForm.get('globalPrice').value === null" (click)="applyPriceToAll()">Apply to all</button>
  <table border formArrayName="orderLines">
  <ng-container *ngFor="let orderLine of orderLines let i=index" [formGroupName]="i">
    <tr>
       <td>{{orderLine.time | date}}</td>
       <td>{{orderLine.quantity}}</td>
       <td><input formControlName="price" type="number"></td>
    </tr>
</ng-container>
  </table>
</form>

Component

import { Component } from '@angular/core';
import { FormGroup, FormControl, FormArray } from '@angular/forms';

@Component({
  selector: 'my-app',
  templateUrl: './app.component.html',
  styleUrls: [ './app.component.css' ]
})
export class AppComponent  {
  name = 'Angular 6';
  mainForm: FormGroup;
  orderLines = [
    {price: 10, time: new Date(), quantity: 2},
    {price: 20, time: new Date(), quantity: 3},
    {price: 30, time: new Date(), quantity: 3},
    {price: 40, time: new Date(), quantity: 5}
    ]
  constructor() {
    this.mainForm = this.getForm();
  }

  getForm(): FormGroup {
    return new FormGroup({
      globalPrice: new FormControl(),
      orderLines: new FormArray(this.orderLines.map(this.getFormGroupForLine))
    })
  }

  getFormGroupForLine(orderLine: any): FormGroup {
    return new FormGroup({
      price: new FormControl(orderLine.price)
    })
  }

  applyPriceToAll() {
    const formLines = this.mainForm.get('orderLines') as FormArray;
    const globalPrice = this.mainForm.get('globalPrice').value;
    formLines.controls.forEach(control => control.get('price').setValue(globalPrice));
    // optionally recheck value and validity without emit event.
  }

  submitForm() {

  }
}

Flutter: Setting the height of the AppBar

You can use PreferredSize:

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Example',
      home: Scaffold(
        appBar: PreferredSize(
          preferredSize: Size.fromHeight(50.0), // here the desired height
          child: AppBar(
            // ...
          )
        ),
        body: // ...
      )
    );
  }
}

installation app blocked by play protect

If you are using some trackers like google analytics or amplitude and you are trying to release your app in another platforms other than Google Play, this errors appears for users. So there are two possible solutions:

  1. Use special trackers in your app (firebase and appmetrica are tested and are ok)
  2. Release your app in Google Play

Axios Delete request with body and headers?

I encountered the same problem... I solved it by creating a custom axios instance. and using that to make a authenticated delete request..

const token = localStorage.getItem('token');
const request = axios.create({
        headers: {
            Authorization: token
        }
    });

await request.delete('<your route>, { data: { <your data> }});

What is the point of WORKDIR on Dockerfile?

You can think of WORKDIR like a cd inside the container (it affects commands that come later in the Dockerfile, like the RUN command). If you removed WORKDIR in your example above, RUN npm install wouldn't work because you would not be in the /usr/src/app directory inside your container.

I don't see how this would be related to where you put your Dockerfile (since your Dockerfile location on the host machine has nothing to do with the pwd inside the container). You can put the Dockerfile wherever you'd like in your project. However, the first argument to COPY is a relative path, so if you move your Dockerfile you may need to update those COPY commands.

Handling back button in Android Navigation Component

If you are using BaseFragment for your app then you can add onBackPressedDispatcher to your base fragment.

//Make a BaseFragment for all your fragments
abstract class BaseFragment : Fragment() {

private lateinit var callback: OnBackPressedCallback

/**
 * SetBackButtonDispatcher in OnCreate
 */

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setBackButtonDispatcher()
}

/**
 * Adding BackButtonDispatcher callback to activity
 */
private fun setBackButtonDispatcher() {
    callback = object : OnBackPressedCallback(true) {
        override fun handleOnBackPressed() {
            onBackPressed()
        }
    }
    requireActivity().onBackPressedDispatcher.addCallback(this, callback)
}

/**
 * Override this method into your fragment to handleBackButton
 */
  open fun onBackPressed() {
  }

}

Override onBackPressed() in your fragment by extending basefragment

//How to use this into your fragment
class MyFragment() : BaseFragment(){

private lateinit var mView: View

override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
    mView = inflater.inflate(R.layout.fragment_my, container, false)
    return mView.rootView
}

override fun onBackPressed() {
    //Write your code here on back pressed.
}

}

Under which circumstances textAlign property works in Flutter?

textAlign property only works when there is a more space left for the Text's content. Below are 2 examples which shows when textAlign has impact and when not.


No impact

For instance, in this example, it won't have any impact because there is no extra space for the content of the Text.

Text(
  "Hello",
  textAlign: TextAlign.end, // no impact
),

enter image description here


Has impact

If you wrap it in a Container and provide extra width such that it has more extra space.

Container(
  width: 200,
  color: Colors.orange,
  child: Text(
    "Hello",
    textAlign: TextAlign.end, // has impact
  ),
)

enter image description here

Deprecated Gradle features were used in this build, making it incompatible with Gradle 5.0

If you're using react-native then please try the below commands first before running your project:

  1. npm install --save-dev jetifier
  2. npx jetify

Now run your project again. Hope this will work.

Please run `npm cache clean`

As of npm@5, the npm cache self-heals from corruption issues and data extracted from the cache is guaranteed to be valid. If you want to make sure everything is consistent, use npm cache verify instead. On the other hand, if you're debugging an issue with the installer, you can use npm install --cache /tmp/empty-cache to use a temporary cache instead of nuking the actual one.

If you're sure you want to delete the entire cache, rerun:

npm cache clean --force

A complete log of this run can be found in /Users/USERNAME/.npm/_logs/2019-01-08T21_29_30_811Z-debug.log.

Confirm password validation in Angular 6

I am using angular 6 and I have been searching on best way to match password and confirm password. This can also be used to match any two inputs in a form. I used Angular Directives. I have been wanting to use them

ng g d compare-validators --spec false and i will be added in your module. Below is the directive

import { Directive, Input } from '@angular/core';
import { Validator, NG_VALIDATORS, AbstractControl, ValidationErrors } from '@angular/forms';
import { Subscription } from 'rxjs';

@Directive({
  // tslint:disable-next-line:directive-selector
  selector: '[compare]',
  providers: [{ provide: NG_VALIDATORS, useExisting: CompareValidatorDirective, multi: true}]
})
export class CompareValidatorDirective implements Validator {
  // tslint:disable-next-line:no-input-rename
  @Input('compare') controlNameToCompare;

  validate(c: AbstractControl): ValidationErrors | null {
    if (c.value.length < 6 || c.value === null) {
      return null;
    }
    const controlToCompare = c.root.get(this.controlNameToCompare);

    if (controlToCompare) {
      const subscription: Subscription = controlToCompare.valueChanges.subscribe(() => {
        c.updateValueAndValidity();
        subscription.unsubscribe();
      });
    }

    return controlToCompare && controlToCompare.value !== c.value ? {'compare': true } : null;
  }

}

Now in your component

<div class="col-md-6">
              <div class="form-group">
                <label class="bmd-label-floating">Password</label>
                <input type="password" class="form-control" formControlName="usrpass" [ngClass]="{ 'is-invalid': submitAttempt && f.usrpass.errors }">
                <div *ngIf="submitAttempt && signupForm.controls['usrpass'].errors" class="invalid-feedback">
                  <div *ngIf="signupForm.controls['usrpass'].errors.required">Your password is required</div>
                  <div *ngIf="signupForm.controls['usrpass'].errors.minlength">Password must be at least 6 characters</div>
                </div>
              </div>
            </div>
            <div class="col-md-6">
              <div class="form-group">
                <label class="bmd-label-floating">Confirm Password</label>
                <input type="password" class="form-control" formControlName="confirmpass" compare = "usrpass"
                [ngClass]="{ 'is-invalid': submitAttempt && f.confirmpass.errors }">
                <div *ngIf="submitAttempt && signupForm.controls['confirmpass'].errors" class="invalid-feedback">
                  <div *ngIf="signupForm.controls['confirmpass'].errors.required">Your confirm password is required</div>
                  <div *ngIf="signupForm.controls['confirmpass'].errors.minlength">Password must be at least 6 characters</div>
                  <div *ngIf="signupForm.controls['confirmpass'].errors['compare']">Confirm password and Password dont match</div>
                </div>
              </div>
            </div>

I hope this one helps