Programs & Examples On #Spring roo

Spring Roo is a lightweight tool aimed at developer productivity. Via an intuitive command line interface it supports operations such as Java web project creation, persistence configuration and view scaffolding. Roo creates a Java web project that uses the Spring framework, and leverage some best well known practices in Java development such as dependency injection, aspect oriented programming, object/relational mapping (O/RM).

Where can I download mysql jdbc jar from?

If you have WL server installed, pick it up from under
\Oracle\Middleware\wlserver_10.3\server\lib\mysql-connector-java-commercial-5.1.17-bin.jar

Otherwise, download it from:
http://www.java2s.com/Code/JarDownload/mysql/mysql-connector-java-5.1.17-bin.jar.zip

Process with an ID #### is not running in visual studio professional 2013 update 3

I have the same problem. Here are some of the things I've done that haven't worked:

  1. Delete the .vs folder in my project
  2. Delete the IIS Express folder in My Documents
  3. Add _CSRUN_DISABLE_WORKAROUNDS to environment variable
  4. Restart the computer
  5. Restart Visual Studio
  6. Change the port
  7. Even re-install visual studio
  8. Uninstall IIS 10.0 Express via Control Panel, then reinstall

I've tried almost all the solutions I got from several forums and none of them have worked.

Finally I found the source of the problem. The source of the problem is not from my project nor from my visual studio, but from my IIS.

When I open iisexpress.exe from C:\Program Files\IISExpress, the command prompt closes immediately. If your IIS Express is fine, then what will appear is as shown below.

iisexpress.exe if success

What I do is reset or reinstall IIS Express via Turn Windows Features on or off in Control Panel. And follow the step by step contained in the following link

My Worked Solution

This is the only way that worked for me, and hopefully it will help the others too.

Convert PDF to PNG using ImageMagick

Reducing the image size before output results in something that looks sharper, in my case:

convert -density 300 a.pdf -resize 25% a.png

Enable the display of line numbers in Visual Studio

Options -> Text Editor -> All Languages -> Line Number checkbox enter image description here

Set LIMIT with doctrine 2?

I use Doctrine\ORM\Tools\Pagination\Paginator for this, and it works perfectly (doctrine 2.2).

$dql = "SELECT p, c FROM BlogPost p JOIN p.comments c";
$query = $entityManager->createQuery($dql)
                       ->setFirstResult(0)
                       ->setMaxResults(10);

$paginator = new Paginator($query, $fetchJoinCollection = true);

Why is the minidlna database not being refreshed?

AzP already provided most of the information, but some of it is incorrect.

First of all, there is no such option inotify_interval. The only option that exists is notify_interval and has nothing to do with inotify.

So to clarify, notify_interval controls how frequently the (mini)dlna server announces itself in the network. The default value of 895 means it will announce itself about once every 15 minutes, meaning clients will need at most 15 minutes to find the server. I personally use 1-5 minutes depending on client volatility in the network.

In terms of getting minidlna to find files that have been added, there are two options:

  • The first is equivalent to removing the file files.db and consists in restarting minidlna while passing the -R argument, which forces a full rescan and builds the database from scratch. Since version 1.2.0 there's now also the -r argument which performs a rebuild action. This preserves any existing database and drops and adds old and new records, respectively.
  • The second is to rely on inotify events by setting inotify=yes and restarting minidlna. If inotify is set to =no, the only option to update the file database is the forced full rescan.

Additionally, in order to have inotify working, the file-system must support inotify events, which is not the case in most remote file-systems. If you have minidlna running over NFS it will not see any inotify events because these are generated on the server side and not on the client.

Finally, even if inotify is working and is supported by the file-system, the user under which minidlna is running must be able to read the file, otherwise it will not be able to retrieve necessary metadata. In this case, the logfile (usually /var/log/minidlna.log) should contain useful information.

How to view/delete local storage in Firefox?

I could not use localStorage directly in the Firefox (v27) console. I got the error:

[Exception... "Component is not available" nsresult: "0x80040111 (NS_ERROR_NOT_AVAILABLE)" location: "JS frame :: debugger eval code :: :: line 1" data: no]

What worked was:

window.content.localStorage

PHP: How to get referrer URL?

$_SERVER['HTTP_REFERER'] will give you the referrer page's URL if there exists any. If users use a bookmark or directly visit your site by manually typing in the URL, http_referer will be empty. Also if the users are posting to your page programatically (CURL) then they're not obliged to set the http_referer as well. You're missing all _, is that a typo?

How can I get the current screen orientation?

getActivity().getResources().getConfiguration().orientation

this command returns int value 1 for Portrait and 2 for Landscape

angular2 submit form by pressing enter without submit button

You can also add (keyup.enter)="xxxx()"

What are best practices for multi-language database design?

I recommend the answer posted by Martin.

But you seem to be concerned about your queries getting too complex:

To create localized table for every table is making design and querying complex...

So you might be thinking, that instead of writing simple queries like this:

SELECT price, name, description FROM Products WHERE price < 100

...you would need to start writing queries like that:

SELECT
  p.price, pt.name, pt.description
FROM
  Products p JOIN ProductTranslations pt
  ON (p.id = pt.id AND pt.lang = "en")
WHERE
  price < 100

Not a very pretty perspective.

But instead of doing it manually you should develop your own database access class, that pre-parses the SQL that contains your special localization markup and converts it to the actual SQL you will need to send to the database.

Using that system might look something like this:

db.setLocale("en");
db.query("SELECT p.price, _(p.name), _(p.description)
          FROM _(Products p) WHERE price < 100");

And I'm sure you can do even better that that.

The key is to have your tables and fields named in uniform way.

Error: No toolchains found in the NDK toolchains folder for ABI with prefix: llvm

Upgrade your Gradle Plugin

  1. com.android.tools.build:gradle:3.1.4
    Upgrade gradle wraperpropeties

    distributionUrl=https://services.gradle.org/distributions/gradle-4.4-all.zip

How to call loading function with React useEffect only once

leave the dependency array blank . hope this will help you understand better.

   useEffect(() => {
      doSomething()
    }, []) 

empty dependency array runs Only Once, on Mount

useEffect(() => {
  doSomething(value)
}, [value])  

pass value as a dependency. if dependencies has changed since the last time, the effect will run again.

useEffect(() => {
  doSomething(value)
})  

no dependency. This gets called after every render.

Basic http file downloading and saving to disk in python?

I use wget.

Simple and good library if you want to example?

import wget

file_url = 'http://johndoe.com/download.zip'

file_name = wget.download(file_url)

wget module support python 2 and python 3 versions

Can I convert a C# string value to an escaped string literal

Hallgrim's answer was excellent. Here's a small tweak in case you need to parse out additional whitespace characters and linebreaks with a c# regular expression. I needed this in the case of a serialized Json value for insertion into google sheets and ran into trouble as the code was inserting tabs, +, spaces, etc.

  provider.GenerateCodeFromExpression(new CodePrimitiveExpression(input), writer, null);
  var literal = writer.ToString();
  var r2 = new Regex(@"\"" \+.\n[\s]+\""", RegexOptions.ECMAScript);
  literal = r2.Replace(literal, "");
  return literal;

Git status ignore line endings / identical files / windows & linux environment / dropbox / mled

Use .gitattributes instead, with the following setting:

# Ignore all differences in line endings
*        -crlf

.gitattributes would be found in the same directory as your global .gitconfig. If .gitattributes doesn't exist, add it to that directory. After adding/changing .gitattributes you will have to do a hard reset of the repository in order to successfully apply the changes to existing files.

Is right click a Javascript event?

This is worked with me

if (evt.xa.which == 3) 
{
    alert("Right mouse clicked");
}

Checking if a variable is initialized

Variable that is not defined will cause compilation error.

What you're asking is about checking if it is initialized. But initialization is just a value, that you should choose and assign in the constructor.

For example:

class MyClass
{
    MyClass() : mCharacter('0'), mDecimal(-1.0){};
    void SomeMethod();

    char mCharacter;
    double mDecimal;
};

void MyClass::SomeMethod()
{
    if ( mCharacter != '0')
    {
        // touched after the constructor
        // do something with mCharacter.
    }

    if ( mDecimal != -1.0 )
    {
        // touched after the constructor
        // define mDecimal.
    }
}

You should initialize to a default value that will mean something in the context of your logic, of course.

python pandas dataframe columns convert to dict key and value

With pandas it can be done as:

If lakes is your DataFrame:

area_dict = lakes.to_dict('records')

How do I install the yaml package for Python?

Debian-based systems:

$ sudo aptitude install python-yaml

or newer for python3

$ sudo aptitude install python3-yaml

How to change a single value in a NumPy array?

Is this what you are after? Just index the element and assign a new value.

A[2,1]=150

A
Out[345]: 
array([[ 1,  2,  3,  4],
       [ 5,  6,  7,  8],
       [ 9, 150, 11, 12],
       [13, 14, 15, 16]])

Delaying a jquery script until everything else has loaded

Have you tried loading all the initialization functions using the $().ready, running the jQuery function you wanted last?

Perhaps you can use setTimeout() on the $().ready function you wanted to run, calling the functionality you wanted to load.

Or, use setInterval() and have the interval check to see if all the other load functions have completed (store the status in a boolean variable). When conditions are met, you could cancel the interval and run the load function.

what is the use of "response.setContentType("text/html")" in servlet

response.setContentType("text/html");

Above code would be include in "HTTP response" to inform the browser about the format of the response, so that the browser can interpret it.

Spark difference between reduceByKey vs groupByKey vs aggregateByKey vs combineByKey

Then apart from these 4, we have

foldByKey which is same as reduceByKey but with a user defined Zero Value.

AggregateByKey takes 3 parameters as input and uses 2 functions for merging(one for merging on same partitions and another to merge values across partition. The first parameter is ZeroValue)

whereas

ReduceBykey takes 1 parameter only which is a function for merging.

CombineByKey takes 3 parameter and all 3 are functions. Similar to aggregateBykey except it can have a function for ZeroValue.

GroupByKey takes no parameter and groups everything. Also, it is an overhead for data transfer across partitions.

posting hidden value

You should never assume register_global_variables is turned on. Even if it is, it's deprecated and you should never use it that way.

Refer directly to the $_POST or $_GET variables. Most likely your form is POSTing, so you'd want your code to look something along the lines of this:

<input type="hidden" name="date" id="hiddenField" value="<?php echo $_POST['date'] ?>" />

If this doesn't work for you right away, print out the $_POST or $_GET variable on the page that would have the hidden form field and determine exactly what you want and refer to it.

echo "<pre>";
print_r($_POST);
echo "</pre>";

iOS Remote Debugging

You cannot directly remote debug Chrome on iOS currently. It uses a uiWebView that may act subtly different than Mobile Safari.

You have a few options.

Option 1: Remote-debug Mobile Safari using Safari's inspector. If your issue reproduces in Mobile Safari, this is definitely the best way to go. In fact, going through the iOS simulator is even easier.

Option 2: Use Weinre for a slimmed down debugging experience. Weinre doesn't have much features but sometimes it's good enough.

Option 3: Remote debug a proper uiWebView that functions the same.

Here's the best way to do this. You'll need to install XCode.

  1. Go to github.com/paulirish/iOS-WebView-App and "Download Zip" or clone.
  2. Open XCode, open existing project, and choose the project you just downloaded.
  3. Open WebViewAppDelegate.m and change the urlString to be the URL you want to test.
  4. Run the app in the iOS Simulator.
  5. Open Safari, Open the Develop Menu, Choose iOS Simulator and select your webview.
  6. Safari Inspector will now be inspecting your uiWebView.

enter image description here

enter image description here

enter image description here

Move cursor to end of file in vim

If you plan to write the next line, ESCGo will do the carriage return and put you in insert mode on the next line (at the end of the file), saving a couple more keystrokes.

Single Result from Database by using mySQLi

If you assume just one result you could do this as in Edwin suggested by using specific users id.

$someUserId = 'abc123';

$stmt = $mysqli->prepare("SELECT ssfullname, ssemail FROM userss WHERE user_id = ?");
$stmt->bind_param('s', $someUserId);

$stmt->execute();

$stmt->bind_result($ssfullname, $ssemail);
$stmt->store_result();
$stmt->fetch();

ChromePhp::log($ssfullname, $ssemail); //log result in chrome if ChromePhp is used.

OR as "Your Common Sense" which selects just one user.

$stmt = $mysqli->prepare("SELECT ssfullname, ssemail FROM userss ORDER BY ssid LIMIT 1");

$stmt->execute();
$stmt->bind_result($ssfullname, $ssemail);
$stmt->store_result();
$stmt->fetch();

Nothing really different from the above except for PHP v.5

What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN?

An SQL JOIN clause is used to combine rows from two or more tables, based on a common field between them.

There are different types of joins available in SQL:

INNER JOIN: returns rows when there is a match in both tables.

LEFT JOIN: returns all rows from the left table, even if there are no matches in the right table.

RIGHT JOIN: returns all rows from the right table, even if there are no matches in the left table.

FULL JOIN: It combines the results of both left and right outer joins.

The joined table will contain all records from both the tables and fill in NULLs for missing matches on either side.

SELF JOIN: is used to join a table to itself as if the table were two tables, temporarily renaming at least one table in the SQL statement.

CARTESIAN JOIN: returns the Cartesian product of the sets of records from the two or more joined tables.

WE can take each first four joins in Details :

We have two tables with the following values.

TableA

id  firstName                  lastName
.......................................
1   arun                        prasanth                 
2   ann                         antony                   
3   sruthy                      abc                      
6   new                         abc                                           

TableB

id2 age Place
................
1   24  kerala
2   24  usa
3   25  ekm
5   24  chennai

....................................................................

INNER JOIN

Note :it gives the intersection of the two tables, i.e. rows they have common in TableA and TableB

Syntax

SELECT table1.column1, table2.column2...
  FROM table1
 INNER JOIN table2
    ON table1.common_field = table2.common_field;

Apply it in our sample table :

SELECT TableA.firstName,TableA.lastName,TableB.age,TableB.Place
  FROM TableA
 INNER JOIN TableB
    ON TableA.id = TableB.id2;

Result Will Be

firstName       lastName       age  Place
..............................................
arun            prasanth        24  kerala
ann             antony          24  usa
sruthy          abc             25  ekm

LEFT JOIN

Note : will give all selected rows in TableA, plus any common selected rows in TableB.

Syntax

SELECT table1.column1, table2.column2...
  FROM table1
  LEFT JOIN table2
    ON table1.common_field = table2.common_field;

Apply it in our sample table :

SELECT TableA.firstName,TableA.lastName,TableB.age,TableB.Place
  FROM TableA
  LEFT JOIN TableB
    ON TableA.id = TableB.id2;

Result

firstName                   lastName                    age   Place
...............................................................................
arun                        prasanth                    24    kerala
ann                         antony                      24    usa
sruthy                      abc                         25    ekm
new                         abc                         NULL  NULL

RIGHT JOIN

Note : will give all selected rows in TableB, plus any common selected rows in TableA.

Syntax

SELECT table1.column1, table2.column2...
  FROM table1
 RIGHT JOIN table2
    ON table1.common_field = table2.common_field;

Apply it in our sample table :

SELECT TableA.firstName,TableA.lastName,TableB.age,TableB.Place
  FROM TableA
 RIGHT JOIN TableB
    ON TableA.id = TableB.id2;

Result

firstName                   lastName                    age     Place
...............................................................................
arun                        prasanth                    24     kerala
ann                         antony                      24     usa
sruthy                      abc                         25     ekm
NULL                        NULL                        24     chennai

FULL JOIN

Note :It will return all selected values from both tables.

Syntax

SELECT table1.column1, table2.column2...
  FROM table1
  FULL JOIN table2
    ON table1.common_field = table2.common_field;

Apply it in our sample table :

SELECT TableA.firstName,TableA.lastName,TableB.age,TableB.Place
  FROM TableA
  FULL JOIN TableB
    ON TableA.id = TableB.id2;

Result

firstName                   lastName                    age    Place
...............................................................................
arun                        prasanth                    24    kerala
ann                         antony                      24    usa
sruthy                      abc                         25    ekm
new                         abc                         NULL  NULL
NULL                        NULL                        24    chennai

Interesting Fact

For INNER joins the order doesn't matter

For (LEFT, RIGHT or FULL) OUTER joins,the order matter

Better to go check this Link it will give you interesting details about join order

Batch file to delete folders older than 10 days in Windows 7

Adapted from this answer to a very similar question:

FORFILES /S /D -10 /C "cmd /c IF @isdir == TRUE rd /S /Q @path"

You should run this command from within your d:\study folder. It will delete all subfolders which are older than 10 days.

The /S /Q after the rd makes it delete folders even if they are not empty, without prompting.

I suggest you put the above command into a .bat file, and save it as d:\study\cleanup.bat.

Python requests - print entire http request (raw)?

import requests

response = requests.post('http://httpbin.org/post', data={'key1':'value1'})
print(response.request.url)
print(response.request.body)
print(response.request.headers)

Response objects have a .request property which is the original PreparedRequest object that was sent.

Eclipse error: R cannot be resolved to a variable

I assume you have updated ADT with version 22 and R.java file is not getting generated.

If this is the case, then here is the solution:

Hope you know Android studio has gradle building tool. Same as in eclipse they have given new component in the Tools folder called Android SDK Build-tools that needs to be installed. Open the Android SDK Manager, select the newly added build tools, install it, restart the SDK Manager after the update.

enter image description here

How to prevent browser to invoke basic auth popup and handle 401 error using Jquery?

In Safari, you can use synchronous requests to avoid the browser to display the popup. Of course, synchronous requests should only be used in this case to check user credentials... You can use a such request before sending the actual request which may cause a bad user experience if the content (sent or received) is quite heavy.

    var xmlhttp=new XMLHttpRequest;
    xmlhttp.withCredentials=true;
    xmlhttp.open("POST",<YOUR UR>,false,username,password);
    xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");
    xmlhttp.setRequestHeader('X-Requested-With', 'XMLHttpRequest');

How to redirect a URL path in IIS?

Here's the config for ISAPI_Rewrite 3:

RewriteBase /

RewriteCond %{HTTP_HOST} ^mysite.org.uk$ [NC]

RewriteRule ^stuff/(.+)$ http://stuff.mysite.org.uk/$1 [NC,R=301,L]

How to use lifecycle method getDerivedStateFromProps as opposed to componentWillReceiveProps

As mentioned by Dan Abramov

Do it right inside render

We actually use that approach with memoise one for any kind of proxying props to state calculations.

Our code looks this way

// ./decorators/memoized.js  
import memoizeOne from 'memoize-one';

export function memoized(target, key, descriptor) {
  descriptor.value = memoizeOne(descriptor.value);
  return descriptor;
}

// ./components/exampleComponent.js
import React from 'react';
import { memoized } from 'src/decorators';

class ExampleComponent extends React.Component {
  buildValuesFromProps() {
    const {
      watchedProp1,
      watchedProp2,
      watchedProp3,
      watchedProp4,
      watchedProp5,
    } = this.props
    return {
      value1: buildValue1(watchedProp1, watchedProp2),
      value2: buildValue2(watchedProp1, watchedProp3, watchedProp5),
      value3: buildValue3(watchedProp3, watchedProp4, watchedProp5),
    }
  }

  @memoized
  buildValue1(watchedProp1, watchedProp2) {
    return ...;
  }

  @memoized
  buildValue2(watchedProp1, watchedProp3, watchedProp5) {
    return ...;
  }

  @memoized
  buildValue3(watchedProp3, watchedProp4, watchedProp5) {
    return ...;
  }

  render() {
    const {
      value1,
      value2,
      value3
    } = this.buildValuesFromProps();

    return (
      <div>
        <Component1 value={value1}>
        <Component2 value={value2}>
        <Component3 value={value3}>
      </div>
    );
  }
}

The benefits of it are that you don't need to code tons of comparison boilerplate inside getDerivedStateFromProps or componentWillReceiveProps and you can skip copy-paste initialization inside a constructor.

NOTE:

This approach is used only for proxying the props to state, in case you have some inner state logic it still needs to be handled in component lifecycles.

Checking for empty or null JToken in a JObject

There is also a type - JTokenType.Undefined.

This check must be included in @Brian Rogers answer.

token.Type == JTokenType.Undefined

What is the difference between logical data model and conceptual data model?

This is an old question and maybe this comes way too late, but I don't see one very important aspect necessary to answering the question. That is, the TARGET audience for the data model. The Conceptual Data Model is the model generated from business analysis, from interviews with the BUSINESS about their data. It is not so much "high level" as it is the business's understanding of their data, business rules captured in the relationships between "candidate" entities. At this point, you are capturing the things of importance to the business (Employee, Customer, Contract, Account, etc.) and the relationships between them. The final Conceptual Data Model may be somewhat abstract -- for instance, treating Individuals and Organizations entering into a contract as subtypes of a "Party", Contractors and Permanent Employees as subtypes of an Employee, even Employees and Customers subtypes of "Person" -- but it is a document that a data modeler develops from discussions with the business SMEs and presents to the business for validation.

The Logical Data Model is not just "more detail" -- where useful and important, a Conceptual Data Model may well have attributes included -- it is the ARCHITECTURE document, the model that is presented to the software analysts/engineers to explain and specify the data requirements. It will resolve many-to-many relationships to association tables and will define all attributes, with examples and constraints, so that code can be written against the architecture.

The Physical model is that Logical Model generated specifically for a particular environment, such as SQL Server or Teradata or Oracle or whatever. It will have keys, indexes, partitions, or whatever is needed to implement, based on sizing, access frequency, security constraints, etc.

So, if you are being asked to develop a Conceptual Data Model, you are being asked to design the solution (or part of it) from scratch, getting your information from the business. There's more to it, but I hope that answers the question.

ignoring any 'bin' directory on a git project

Adding **/bin/ to the .gitignore file did the trick for me (Note: bin folder wasn't added to index).

Can you have if-then-else logic in SQL?

The CASE statement is the closest to an IF statement in SQL, and is supported on all versions of SQL Server:

SELECT CASE <variable> 
           WHEN <value>      THEN <returnvalue> 
           WHEN <othervalue> THEN <returnthis> 
           ELSE <returndefaultcase> 
       END 
  FROM <table> 

'Static readonly' vs. 'const'

Another difference between declaring const and static readonly is in memory allocation.

A static field belongs to the type of an object rather than to an instance of that type. As a result, once the class is referenced for the first time, the static field would "live" in the memory for the rest of time, and the same instance of the static field would be referenced by all instances of the type.

On the other hand, a const field "belongs to an instance of the type.

If memory of deallocation is more important for you, prefer to use const. If speed, then use static readonly.

How to clean up R memory (without the need to restart my PC)?

There is only so much you can do with rm() and gc(). As suggested by Gavin Simpson, even if you free the actual memory in R, Windows often won't reclaim it until you close R or it is needed because all the apparent Windows memory fills up.

This usually isn't a problem. However, if you are running large loops this can sometimes lead to fragmented memory in the long term, such that even if you free the memory and restart R - the fragmented memory may prevent you allocating large chunks of memory. Especially if other applications were allocated fragmented memory while you were running R. rm() and gc() may delay the inevitable, but more RAM is better.

How to run java application by .bat file

Sure, call the java executable.

Mine is C:\Program Files\Java\jre6\bin\java.exe, so to run it I would do

C:\Program Files\Java\jre6\bin\java.exe -jar myjarfile.jar

How to make a hyperlink in telegram without using bots?

Try this link format: https://t.me/[YourUserName]

I was looking for such a thing, BUT with text in (like the one that WhatsApp got)

Make an image follow mouse pointer

Here's my code (not optimized but a full working example):

<head>
<style>
#divtoshow {position:absolute;display:none;color:white;background-color:black}
#onme {width:150px;height:80px;background-color:yellow;cursor:pointer}
</style>
<script type="text/javascript">
var divName = 'divtoshow'; // div that is to follow the mouse (must be position:absolute)
var offX = 15;          // X offset from mouse position
var offY = 15;          // Y offset from mouse position

function mouseX(evt) {if (!evt) evt = window.event; if (evt.pageX) return evt.pageX; else if (evt.clientX)return evt.clientX + (document.documentElement.scrollLeft ?  document.documentElement.scrollLeft : document.body.scrollLeft); else return 0;}
function mouseY(evt) {if (!evt) evt = window.event; if (evt.pageY) return evt.pageY; else if (evt.clientY)return evt.clientY + (document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop); else return 0;}

function follow(evt) {
    var obj = document.getElementById(divName).style;
    obj.left = (parseInt(mouseX(evt))+offX) + 'px';
    obj.top = (parseInt(mouseY(evt))+offY) + 'px'; 
    }
document.onmousemove = follow;
</script>
</head>
<body>
<div id="divtoshow">test</div>
<br><br>
<div id='onme' onMouseover='document.getElementById(divName).style.display="block"' onMouseout='document.getElementById(divName).style.display="none"'>Mouse over this</div>
</body>

Creating a border like this using :before And :after Pseudo-Elements In CSS?

#footer:after
{
   content: "";
    width: 40px;
    height: 3px;
    background-color: #529600;
    left: 0;
    position: relative;
    display: block;
    top: 10px;
}

How to automatically generate getters and setters in Android Studio

Use Ctrl+Enter on Mac to get list of options to generate setter, getter, constructor etc

enter image description here

How do I initialize a TypeScript Object with a JSON-Object?

you can use Object.assign I don't know when this was added, I'm currently using Typescript 2.0.2, and this appears to be an ES6 feature.

client.fetch( '' ).then( response => {
        return response.json();
    } ).then( json => {
        let hal : HalJson = Object.assign( new HalJson(), json );
        log.debug( "json", hal );

here's HalJson

export class HalJson {
    _links: HalLinks;
}

export class HalLinks implements Links {
}

export interface Links {
    readonly [text: string]: Link;
}

export interface Link {
    readonly href: URL;
}

here's what chrome says it is

HalJson {_links: Object}
_links
:
Object
public
:
Object
href
:
"http://localhost:9000/v0/public

so you can see it doesn't do the assign recursively

What's an object file in C?

An object file is the real output from the compilation phase. It's mostly machine code, but has info that allows a linker to see what symbols are in it as well as symbols it requires in order to work. (For reference, "symbols" are basically names of global objects, functions, etc.)

A linker takes all these object files and combines them to form one executable (assuming that it can, ie: that there aren't any duplicate or undefined symbols). A lot of compilers will do this for you (read: they run the linker on their own) if you don't tell them to "just compile" using command-line options. (-c is a common "just compile; don't link" option.)

How to link HTML5 form action to Controller ActionResult method in ASP.NET MVC 4

Here I'm basically wrapping a button in a link. The advantage is that you can post to different action methods in the same form.

<a href="Controller/ActionMethod">
    <input type="button" value="Click Me" />
</a>

Adding parameters:

<a href="Controller/ActionMethod?userName=ted">
    <input type="button" value="Click Me" />
</a>

Adding parameters from a non-enumerated Model:

<a href="Controller/[email protected]">
    <input type="button" value="Click Me" />
</a>

You can do the same for an enumerated Model too. You would just have to reference a single entity first. Happy Coding!

DNS caching in linux

Firefox contains a dns cache. To disable the DNS cache:

  1. Open your browser
  2. Type in about:config in the address bar
  3. Right click on the list of Properties and select New > Integer in the Context menu
  4. Enter 'network.dnsCacheExpiration' as the preference name and 0 as the integer value

When disabled, Firefox will use the DNS cache provided by the OS.

How to add parameters into a WebRequest?

I have a feeling that the username and password that you are sending should be part of the Authorization Header. So the code below shows you how to create the Base64 string of the username and password. I also included an example of sending the POST data. In my case it was a phone_number parameter.

string credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes(_username + ":" + _password));

HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(Request);
webRequest.Headers.Add("Authorization", string.Format("Basic {0}", credentials));
webRequest.ContentType = "application/x-www-form-urlencoded";
webRequest.Method = WebRequestMethods.Http.Post;
webRequest.AllowAutoRedirect = true;
webRequest.Proxy = null;

string data = "phone_number=19735559042"; 
byte[] dataStream = Encoding.UTF8.GetBytes(data);

request.ContentLength = dataStream.Length;
Stream newStream = webRequest.GetRequestStream();
newStream.Write(dataStream, 0, dataStream.Length);
newStream.Close();

HttpWebResponse response = (HttpWebResponse)webRequest.GetResponse();
Stream stream = response.GetResponseStream();
StreamReader streamreader = new StreamReader(stream);
string s = streamreader.ReadToEnd();

Smooth scroll without the use of jQuery

I recently set out to solve this problem in a situation where jQuery wasn't an option, so I'm logging my solution here just for posterity.

var scroll = (function() {

    var elementPosition = function(a) {
        return function() {
            return a.getBoundingClientRect().top;
        };
    };

    var scrolling = function( elementID ) {

        var el = document.getElementById( elementID ),
            elPos = elementPosition( el ),
            duration = 400,
            increment = Math.round( Math.abs( elPos() )/40 ),
            time = Math.round( duration/increment ),
            prev = 0,
            E;

        function scroller() {
            E = elPos();

            if (E === prev) {
                return;
            } else {
                prev = E;
            }

            increment = (E > -20 && E < 20) ? ((E > - 5 && E < 5) ? 1 : 5) : increment;

            if (E > 1 || E < -1) {

                if (E < 0) {
                    window.scrollBy( 0,-increment );
                } else {
                    window.scrollBy( 0,increment );
                }

                setTimeout(scroller, time);

            } else {

                el.scrollTo( 0,0 );

            }
        }

        scroller();
    };

    return {
        To: scrolling
    }

})();

/* usage */
scroll.To('elementID');

The scroll() function uses the Revealing Module Pattern to pass the target element's id to its scrolling() function, via scroll.To('id'), which sets the values used by the scroller() function.

Breakdown

In scrolling():

  • el : the target DOM object
  • elPos : returns a function via elememtPosition() which gives the position of the target element relative to the top of the page each time it's called.
  • duration : transition time in milliseconds.
  • increment : divides the starting position of the target element into 40 steps.
  • time : sets the timing of each step.
  • prev : the target element's previous position in scroller().
  • E : holds the target element's position in scroller().

The actual work is done by the scroller() function which continues to call itself (via setTimeout()) until the target element is at the top of the page or the page can scroll no more.

Each time scroller() is called it checks the current position of the target element (held in variable E) and if that is > 1 OR < -1 and if the page is still scrollable shifts the window by increment pixels - up or down depending if E is a positive or negative value. When E is neither > 1 OR < -1, or E === prev the function stops. I added the DOMElement.scrollTo() method on completion just to make sure the target element was bang on the top of the window (not that you'd notice it being out by a fraction of a pixel!).

The if statement on line 2 of scroller() checks to see if the page is scrolling (in cases where the target might be towards the bottom of the page and the page can scroll no further) by checking E against its previous position (prev).

The ternary condition below it reduce the increment value as E approaches zero. This stops the page overshooting one way and then bouncing back to overshoot the other, and then bouncing back to overshoot the other again, ping-pong style, to infinity and beyond.

If your page is more that c.4000px high you might want to increase the values in the ternary expression's first condition (here at +/-20) and/or the divisor which sets the increment value (here at 40).

Playing about with duration, the divisor which sets increment, and the values in the ternary condition of scroller() should allow you to tailor the function to suit your page.

  • JSFiddle

  • N.B.Tested in up-to-date versions of Firefox and Chrome on Lubuntu, and Firefox, Chrome and IE on Windows8.

Comment out HTML and PHP together

I agree that Pascal's solution is the way to go, but for those saying that it adds an extra task to remove the comments, you can use the following comment style trick to simplify your life:

<?php /* ?>
<tr>
      <td><?php echo $entry_keyword; ?></td>
      <td><input type="text" name="keyword" value="<?php echo $keyword; ?>" /></td>
    </tr>
    <tr>
      <td><?php echo $entry_sort_order; ?></td>
      <td><input name="sort_order" value="<?php echo $sort_order; ?>" size="1" /></td>
    </tr>
<?php // */ ?>

In order to stop the code block being commented out, simply change the opening comment to:

<?php //* ?>

Facebook share link without JavaScript

Ps 2: As pointed out by Justin, check out Facebook's new Share Dialog. Will leave the answer as is for posterity. This answer is obsolete


Short answer, yes there's a similar option for Facebook, that doesn't require javascript (well, there's some minimal inline JS that is not compulsory, see note).

Ps: The onclick part only helps you customise the popup a little bit but is not required for the code to work ... it will work just fine without it.

Facebook

<a href="https://www.facebook.com/sharer/sharer.php?u=URLENCODED_URL&t=TITLE"
   onclick="javascript:window.open(this.href, '', 'menubar=no,toolbar=no,resizable=yes,scrollbars=yes,height=300,width=600');return false;"
   target="_blank" title="Share on Facebook">
</a>

Twitter

<a href="https://twitter.com/share?url=URLENCODED_URL&via=TWITTER_HANDLE&text=TEXT"
   onclick="javascript:window.open(this.href, '', 'menubar=no,toolbar=no,resizable=yes,scrollbars=yes,height=300,width=600');return false;"
   target="_blank" title="Share on Twitter">
</a>

How to check if an integer is in a given range?

if(i <= 0 || i >=100)

It will work.

Can I stop 100% Width Text Boxes from extending beyond their containers?

This works:

<div>
    <input type="text" 
        style="margin: 5px; padding: 4px; border: 1px solid; 
        width: 200px; width: calc(100% - 20px);">
</div>

The first 'width' is a fallback rule for older browsers.

Why am I getting a NoClassDefFoundError in Java?

In case you have generated-code (EMF, etc.) there can be too many static initialisers which consume all stack space.

See Stack Overflow question How to increase the Java stack size?.

org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'customerService' is defined

By reading your exception , It's sure that you forgot to autowire customerService

You should autowire your customerservice .

make following changes in your controller class

@Controller
public class CustomerController{

    @Autowired
    private Customerservice customerservice;
......other code......

}

Again your service implementation class

write

@Service
public class CustomerServiceImpl implements CustomerService {
    @Autowired
    private CustomerDAO customerDAO;
......other code......

.....add transactional methods
}

If you are using hibernate make necessary changes in your applicationcontext xml file(configuration of session factory is needed).

you should autowire sessionFactory set method in your DAO mplementation

please find samle application context :

<?xml  version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:jee="http://www.springframework.org/schema/jee"
    xmlns:lang="http://www.springframework.org/schema/lang"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:util="http://www.springframework.org/schema/util"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee.xsd
        http://www.springframework.org/schema/lang http://www.springframework.org/schema/lang/spring-lang.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:annotation-config />
    <context:component-scan base-package="com.sparkle" />
    <!-- Configures the @Controller programming model -->
    <mvc:annotation-driven />

    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver" 
            p:prefix="/WEB-INF/jsp/" p:suffix=".jsp" p:order="0" />

    <bean id="messageSource"
        class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
        <property name="basename" value="classpath:messages" />
        <property name="defaultEncoding" value="UTF-8" />
    </bean>
    <!-- <bean id="propertyConfigurer"
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"
        p:location="/WEB-INF/jdbc.properties" /> -->

     <bean id="propertyConfigurer"
        class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="locations">         
        <list>
            <value>/WEB-INF/jdbc.properties</value>          

        </list>    
    </property>     
    </bean>




    <bean id="dataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource"
        p:driverClassName="${jdbc.driverClassName}"
        p:url="${jdbc.databaseurl}" p:username="${jdbc.username}"
        p:password="${jdbc.password}" />


    <bean id="sessionFactory"
        class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="configLocation">
            <value>classpath:hibernate.cfg.xml</value>
        </property>
        <property name="configurationClass">
            <value>org.hibernate.cfg.AnnotationConfiguration</value>
        </property>
        <property name="hibernateProperties">
            <props>
                <prop key="hibernate.dialect">${jdbc.dialect}</prop>
                <prop key="hibernate.show_sql">true</prop>
            </props>
        </property>
    </bean>

    <tx:annotation-driven />


   <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"
          p:sessionFactory-ref="sessionFactory"/>


</beans>

note that i am using jdbc.properties file for jdbc url and driver specification

Correct use of flush() in JPA/Hibernate

Actually, em.flush(), do more than just sends the cached SQL commands. It tries to synchronize the persistence context to the underlying database. It can cause a lot of time consumption on your processes if your cache contains collections to be synchronized.

Caution on using it.

Can CSS detect the number of children an element has?

Working off of Matt's solution, I used the following Compass/SCSS implementation.

@for $i from 1 through 20 {
    li:first-child:nth-last-child( #{$i} ),
    li:first-child:nth-last-child( #{$i} ) ~ li {
      width: calc(100% / #{$i} - 10px);
    }
  }

This allows you to quickly expand the number of items.

AngularJS - add HTML element to dom in directive without jQuery

Why not to try simple (but powerful) html() method:

iElement.html('<svg width="600" height="100" class="svg"></svg>');

Or append as an alternative:

iElement.append('<svg width="600" height="100" class="svg"></svg>');

And , of course , more cleaner way:

 var svg = angular.element('<svg width="600" height="100" class="svg"></svg>');
 iElement.append(svg);

Fiddle: http://jsfiddle.net/cherniv/AgGwK/

ListBox with ItemTemplate (and ScrollBar!)

I pasted your code into test project, added about 20 items and I get usable scroll bars, no problem, and they work as expected. When I only add a couple items (such that scrolling is unnecessary) I get no usable scrollbar. Could this be the case? that you are not adding enough items?

If you remove the ScrollViewer.VerticalScrollBarVisibility="Visible" then the scroll bars only appear when you have need of them.

How to use View.OnTouchListener instead of onClick

The event when user releases his finger is MotionEvent.ACTION_UP. I'm not aware if there are any guidelines which prohibit using View.OnTouchListener instead of onClick(), most probably it depends of situation.

Here's a sample code:

imageButton.setOnTouchListener(new OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        if(event.getAction() == MotionEvent.ACTION_UP){

            // Do what you want
            return true;
        }
        return false;
    }
});

Getting Data from Android Play Store

The Google Play Store doesn't provide this data, so the sites must just be scraping it.

Python: Is there an equivalent of mid, right, and left from BASIC?

These work great for reading left / right "n" characters from a string, but, at least with BBC BASIC, the LEFT$() and RIGHT$() functions allowed you to change the left / right "n" characters too...

E.g.:

10 a$="00000"
20 RIGHT$(a$,3)="ABC"
30 PRINT a$

Would produce:

00ABC

Edit : Since writing this, I've come up with my own solution...

def left(s, amount = 1, substring = ""):
    if (substring == ""):
        return s[:amount]
    else:
        if (len(substring) > amount):
            substring = substring[:amount]
        return substring + s[:-amount]

def right(s, amount = 1, substring = ""):
    if (substring == ""):
        return s[-amount:]
    else:
        if (len(substring) > amount):
            substring = substring[:amount]
        return s[:-amount] + substring

To return n characters you'd call

substring = left(string,<n>)

Where defaults to 1 if not supplied. The same is true for right()

To change the left or right n characters of a string you'd call

newstring = left(string,<n>,substring)

This would take the first n characters of substring and overwrite the first n characters of string, returning the result in newstring. The same works for right().

SQL Query to fetch data from the last 30 days?

Pay attention to one aspect when doing "purchase_date>(sysdate-30)": "sysdate" is the current date, hour, minute and second. So "sysdate-30" is not exactly "30 days ago", but "30 days ago at this exact hour".

If your purchase dates have 00.00.00 in hours, minutes, seconds, better doing:

where trunc(purchase_date)>trunc(sysdate-30)

(this doesn't take hours, minutes and seconds into account).

Entity Framework throws exception - Invalid object name 'dbo.BaseCs'

If you are providing mappings like this:

 protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        modelBuilder.Configurations.Add(new ClassificationMap());
        modelBuilder.Configurations.Add(new CompanyMap());
        modelBuilder.Configurations.Add(new GroupMap());
        ....  
    }

Remember to add the map for BaseCs.

You won't get a compile error if it is missing. But you will get a runtime error when you use the entity.

remove white space from the end of line in linux

sed -i 's/[[:blank:]]\{1,\}$//' YourFile

[:blank:] is for space, tab mainly and {1,} to exclude 'no space at the end' of the substitution process (no big significant impact if line are short and file are small)

Can you center a Button in RelativeLayout?

You can use CENTER_IN_PARENT for relative layout.

Add android:layout_centerInParent="true" to element which you want to center in the RelativeLayout

How to have conditional elements and keep DRY with Facebook React's JSX?

I made https://github.com/ajwhite/render-if recently to safely render elements only if the predicate passes.

{renderIf(1 + 1 === 2)(
  <span>Hello!</span>
)}

or

const ifUniverseIsWorking = renderIf(1 + 1 === 2);

//...

{ifUniverseIsWorking(
  <span>Hello!</span>
)}

RSA Public Key format

Reference Decoder of CRL,CRT,CSR,NEW CSR,PRIVATE KEY, PUBLIC KEY,RSA,RSA Public Key Parser

RSA Public Key

-----BEGIN RSA PUBLIC KEY-----
-----END RSA PUBLIC KEY-----

Encrypted Private Key

-----BEGIN RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
-----END RSA PRIVATE KEY-----

CRL

-----BEGIN X509 CRL-----
-----END X509 CRL-----

CRT

-----BEGIN CERTIFICATE-----
-----END CERTIFICATE-----

CSR

-----BEGIN CERTIFICATE REQUEST-----
-----END CERTIFICATE REQUEST-----

NEW CSR

-----BEGIN NEW CERTIFICATE REQUEST-----
-----END NEW CERTIFICATE REQUEST-----

PEM

-----BEGIN RSA PRIVATE KEY-----
-----END RSA PRIVATE KEY-----

PKCS7

-----BEGIN PKCS7-----
-----END PKCS7-----

PRIVATE KEY

-----BEGIN PRIVATE KEY-----
-----END PRIVATE KEY-----

DSA KEY

-----BEGIN DSA PRIVATE KEY-----
-----END DSA PRIVATE KEY-----

Elliptic Curve

-----BEGIN EC PRIVATE KEY-----
-----END EC PRIVATE KEY-----

PGP Private Key

-----BEGIN PGP PRIVATE KEY BLOCK-----
-----END PGP PRIVATE KEY BLOCK-----

PGP Public Key

-----BEGIN PGP PUBLIC KEY BLOCK-----
-----END PGP PUBLIC KEY BLOCK-----

plot a circle with pyplot

I see plots with the use of (.circle) but based on what you might want to do you can also try this out:

import matplotlib.pyplot as plt
import numpy as np

x = list(range(1,6))
y = list(range(10, 20, 2))

print(x, y)

for i, data in enumerate(zip(x,y)):
    j, k = data
    plt.scatter(j,k, marker = "o", s = ((i+1)**4)*50, alpha = 0.3)

Simple concentric circle plot using linear progressing points

centers = np.array([[5,18], [3,14], [7,6]])
m, n = make_blobs(n_samples=20, centers=[[5,18], [3,14], [7,6]], n_features=2, 
cluster_std = 0.4)
colors = ['g', 'b', 'r', 'm']

plt.figure(num=None, figsize=(7,6), facecolor='w', edgecolor='k')
plt.scatter(m[:,0], m[:,1])

for i in range(len(centers)):

    plt.scatter(centers[i,0], centers[i,1], color = colors[i], marker = 'o', s = 13000, alpha = 0.2)
    plt.scatter(centers[i,0], centers[i,1], color = 'k', marker = 'x', s = 50)

plt.savefig('plot.png')

Circled points of a classification problem.

Zoom to fit: PDF Embedded in HTML

Use iframe tag do display pdf file with zoom fit

<iframe src="filename.pdf" width="" height="" border="0"></iframe>

How can I change the default Django date template format?

What you need is a date template filter.

e.g:

<td>Joined {{user.date_created|date:"F Y" }}<td>

This returns Joined December 2018

IF-THEN-ELSE statements in postgresql

As stated in PostgreSQL docs here:

The SQL CASE expression is a generic conditional expression, similar to if/else statements in other programming languages.

Code snippet specifically answering your question:

SELECT field1, field2,
  CASE
    WHEN field1>0 THEN field2/field1
    ELSE 0
  END 
  AS field3
FROM test

Java 'file.delete()' Is not Deleting Specified File

Be sure to find out your current working directory, and write your filepath relative to it.

This code:

File here = new File(".");
System.out.println(here.getAbsolutePath());

... will print out that directory.

Also, unrelated to your question, try to use File.separator to remain OS-independent. Backslashes work only on Windows.

How can I import a database with MySQL from terminal?

The simplest way to import a database in your MYSQL from the terminal is done by the below-mentioned process -

mysql -u root -p root database_name < path to your .sql file

What I'm doing above is:

  1. Entering to mysql with my username and password (here it is root & root)
  2. After entering the password I'm giving the name of database where I want to import my .sql file. Please make sure the database already exists in your MYSQL
  3. The database name is followed by < and then path to your .sql file. For example, if my file is stored in Desktop, the path will be /home/Desktop/db.sql

That's it. Once you've done all this, press enter and wait for your .sql file to get uploaded to the respective database

ADB Install Fails With INSTALL_FAILED_TEST_ONLY

this works for me adb install -t myapk.apk

CSS Disabled scrolling

I use iFrame to insert the content from another page and CSS mentioned above is NOT working as expected. I have to use the parameter scrolling="no" even if I use HTML 5 Doctype

TypeError: 'DataFrame' object is not callable

It seems you need DataFrame.var:

Normalized by N-1 by default. This can be changed using the ddof argument

var1 = credit_card.var()

Sample:

#random dataframe
np.random.seed(100)
credit_card = pd.DataFrame(np.random.randint(10, size=(5,5)), columns=list('ABCDE'))
print (credit_card)
   A  B  C  D  E
0  8  8  3  7  7
1  0  4  2  5  2
2  2  2  1  0  8
3  4  0  9  6  2
4  4  1  5  3  4

var1 = credit_card.var()
print (var1)
A     8.8
B    10.0
C    10.0
D     7.7
E     7.8
dtype: float64

var2 = credit_card.var(axis=1)
print (var2)
0     4.3
1     3.8
2     9.8
3    12.2
4     2.3
dtype: float64

If need numpy solutions with numpy.var:

print (np.var(credit_card.values, axis=0))
[ 7.04  8.    8.    6.16  6.24]

print (np.var(credit_card.values, axis=1))
[ 3.44  3.04  7.84  9.76  1.84]

Differences are because by default ddof=1 in pandas, but you can change it to 0:

var1 = credit_card.var(ddof=0)
print (var1)
A    7.04
B    8.00
C    8.00
D    6.16
E    6.24
dtype: float64

var2 = credit_card.var(ddof=0, axis=1)
print (var2)
0    3.44
1    3.04
2    7.84
3    9.76
4    1.84
dtype: float64

Round double value to 2 decimal places

You can use the below code to format it to two decimal places

NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];

[formatter setNumberStyle:NSNumberFormatterDecimalStyle];
[formatter setMaximumFractionDigits:2];
[formatter setRoundingMode: NSNumberFormatterRoundUp];

NSString *numberString = [formatter stringFromNumber:[NSNumber numberWithFloat:22.368511]];

NSLog(@"Result...%@",numberString);//Result 22.37

Swift 4:

let formatter = NumberFormatter()
formatter.numberStyle = .decimal
formatter.maximumFractionDigits = 2
formatter.roundingMode = .up

let str = String(describing: formatter.string(from: 12.2345)!)

print(str)

How to display full (non-truncated) dataframe information in html when converting from pandas dataframe to html?

While pd.set_option('display.max_columns', None) sets the number of the maximum columns shown, the option pd.set_option('display.max_colwidth', -1) sets the maximum width of each single field.

For my purposes I wrote a small helper function to fully print huge data frames without affecting the rest of the code, it also reformats float numbers and sets the virtual display width. You may adopt it for your use cases.

def print_full(x):
    pd.set_option('display.max_rows', None)
    pd.set_option('display.max_columns', None)
    pd.set_option('display.width', 2000)
    pd.set_option('display.float_format', '{:20,.2f}'.format)
    pd.set_option('display.max_colwidth', None)
    print(x)
    pd.reset_option('display.max_rows')
    pd.reset_option('display.max_columns')
    pd.reset_option('display.width')
    pd.reset_option('display.float_format')
    pd.reset_option('display.max_colwidth')

What is Python buffer type for?

I think buffers are e.g. useful when interfacing python to native libraries. (Guido van Rossum explains buffer in this mailinglist post).

For example, numpy seems to use buffer for efficient data storage:

import numpy
a = numpy.ndarray(1000000)

the a.data is a:

<read-write buffer for 0x1d7b410, size 8000000, offset 0 at 0x1e353b0>

How do I correctly clean up a Python object?

It seems that the idiomatic way to do this is to provide a close() method (or similar), and call it explicitely.

How to embed a .mov file in HTML?

<object CLASSID="clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B" width="320" height="256" CODEBASE="http://www.apple.com/qtactivex/qtplugin.cab">
    <param name="src" value="sample.mov">
    <param name="qtsrc" value="rtsp://realmedia.uic.edu/itl/ecampb5/demo_broad.mov">
    <param name="autoplay" value="true">
    <param name="loop" value="false">
    <param name="controller" value="true">
    <embed src="sample.mov" qtsrc="rtsp://realmedia.uic.edu/itl/ecampb5/demo_broad.mov" width="320" height="256" autoplay="true" loop="false" controller="true" pluginspage="http://www.apple.com/quicktime/"></embed>
</object>

source is the first search result of the Google

C# ASP.NET Single Sign-On Implementation

UltimateSAML SSO is an OASIS SAML v1.x and v2.0 specifications compliant .NET toolkit. It offers an elegant and easy way to add support for Single Sign-On and Single-Logout SAML to your ASP.NET, ASP.NET MVC, ASP.NET Core, Desktop, and Service applications. The lightweight library helps you provide SSO access to cloud and intranet websites using a single credentials entry.

Detailed UltimateSAML SSO review can be found here

CSS: Force float to do a whole new line

Add to .icons div {width:160px; height:130px;} will work out very nicely

Hope it will help

Doctrine - How to print out the real sql, not just the prepared statement?

Solution:1
====================================================================================

function showQuery($query)
{
    return sprintf(str_replace('?', '%s', $query->getSql()), $query->getParams());
}

// call function  
echo showQuery($doctrineQuery);

Solution:2
====================================================================================

function showQuery($query)
{
    // define vars              
    $output    = NULL;
    $out_query = $query->getSql();
    $out_param = $query->getParams();

    // replace params
   for($i=0; $i<strlen($out_query); $i++) {
       $output .= ( strpos($out_query[$i], '?') !== FALSE ) ? "'" .str_replace('?', array_shift($out_param), $out_query[$i]). "'" : $out_query[$i];
   }

   // output
   return sprintf("%s", $output);
}

// call function  
echo showQuery($doctrineQueryObject);

jQuery set radio button

You can try the following code:

$("input[name=cols][value=" + value + "]").attr('checked', 'checked');

This will set the attribute checked for the radio columns and value as specified.

Determine a user's timezone

Here is a more complete way.

  1. Get the timezone offset for the user
  2. Test some days on daylight saving boundaries to determine if they are in a zone that uses daylight saving.

An excerpt is below:

function TimezoneDetect(){
    var dtDate = new Date('1/1/' + (new Date()).getUTCFullYear());
    var intOffset = 10000; //set initial offset high so it is adjusted on the first attempt
    var intMonth;
    var intHoursUtc;
    var intHours;
    var intDaysMultiplyBy;

    // Go through each month to find the lowest offset to account for DST
    for (intMonth=0;intMonth < 12;intMonth++){
        //go to the next month
        dtDate.setUTCMonth(dtDate.getUTCMonth() + 1);

        // To ignore daylight saving time look for the lowest offset.
        // Since, during DST, the clock moves forward, it'll be a bigger number.
        if (intOffset > (dtDate.getTimezoneOffset() * (-1))){
            intOffset = (dtDate.getTimezoneOffset() * (-1));
        }
    }

    return intOffset;
}

Getting TZ and DST from JS (via Way Back Machine)

What is the difference among col-lg-*, col-md-* and col-sm-* in Bootstrap?

enter image description here

I think this image is pretty good to understand the concept better!

for more detail understanding please go though below link:

https://getbootstrap.com/docs/3.4/css/

How to make RatingBar to show five stars

You can add default rating of five stars in side the xml layout

android:rating="5"

Edit:

<RatingBar
        android:id="@+id/rb_vvm"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:layout_marginBottom="@dimen/space2"
        android:layout_marginTop="@dimen/space1"
        style="@style/RatingBar"
        android:numStars="5"
        android:stepSize="1"
        android:rating="5" />

JavaScript chop/slice/trim off last character in string

@Jason S:

You can use slice! You just have to make sure you know how to use it. Positive #s are relative to the beginning, negative numbers are relative to the end.

js>"12345.00".slice(0,-1) 12345.0

Sorry for my graphomany but post was tagged 'jquery' earlier. So, you can't use slice() inside jQuery because slice() is jQuery method for operations with DOM elements, not substrings ... In other words answer @Jon Erickson suggest really perfect solution.

However, your method will works out of jQuery function, inside simple Javascript. Need to say due to last discussion in comments, that jQuery is very much more often renewable extension of JS than his own parent most known ECMAScript.

Here also exist two methods:

as our:

string.substring(from,to) as plus if 'to' index nulled returns the rest of string. so: string.substring(from) positive or negative ...

and some other - substr() - which provide range of substring and 'length' can be positive only: string.substr(start,length)

Also some maintainers suggest that last method string.substr(start,length) do not works or work with error for MSIE.

How to calculate the sum of the datatable column in asp.net?

You Can use Linq by Name Grouping

  var allEntries = from r in dt.AsEnumerable()
                            select r["Amount"];

using name space using System.Linq;

You can find the sample total,subtotal,grand total in datatable using c# at Myblog

JavaScript unit test tools for TDD

You might also be interested in the unit testing framework that is part of qooxdoo, an open source RIA framework similar to Dojo, ExtJS, etc. but with quite a comprehensive tool chain.

Try the online version of the testrunner. Hint: hit the gray arrow at the top left (should be made more obvious). It's a "play" button that runs the selected tests.

To find out more about the JS classes that let you define your unit tests, see the online API viewer.

For automated UI testing (based on Selenium RC), check out the Simulator project.

Convert an integer to a float number

There is no float type. Looks like you want float64. You could also use float32 if you only need a single-precision floating point value.

package main

import "fmt"

func main() {
    i := 5
    f := float64(i)
    fmt.Printf("f is %f\n", f)
}

Return array in a function

This:

int fillarr(int arr[])

is actually treated the same as:

int fillarr(int *arr)

Now if you really want to return an array you can change that line to

int * fillarr(int arr[]){
    // do something to arr
    return arr;
}

It's not really returning an array. you're returning a pointer to the start of the array address.

But remember when you pass in the array, you're only passing in a pointer. So when you modify the array data, you're actually modifying the data that the pointer is pointing at. Therefore before you passed in the array, you must realise that you already have on the outside the modified result.

e.g.

int fillarr(int arr[]){
   array[0] = 10;
   array[1] = 5;
}

int main(int argc, char* argv[]){
   int arr[] = { 1,2,3,4,5 };

   // arr[0] == 1
   // arr[1] == 2 etc
   int result = fillarr(arr);
   // arr[0] == 10
   // arr[1] == 5    
   return 0;
}

I suggest you might want to consider putting a length into your fillarr function like this.

int * fillarr(int arr[], int length)

That way you can use length to fill the array to it's length no matter what it is.

To actually use it properly. Do something like this:

int * fillarr(int arr[], int length){
   for (int i = 0; i < length; ++i){
      // arr[i] = ? // do what you want to do here
   }
   return arr;
}

// then where you want to use it.
int arr[5];
int *arr2;

arr2 = fillarr(arr, 5);

// at this point, arr & arr2 are basically the same, just slightly
// different types.  You can cast arr to a (char*) and it'll be the same.

If all you're wanting to do is set the array to some default values, consider using the built in memset function.

something like: memset((int*)&arr, 5, sizeof(int));

While I'm on the topic though. You say you're using C++. Have a look at using stl vectors. Your code is likely to be more robust.

There are lots of tutorials. Here is one that gives you an idea of how to use them. http://www.yolinux.com/TUTORIALS/LinuxTutorialC++STL.html

Getting time and date from timestamp with php

Works for me:

select DATE( FROM_UNIXTIME( columnname ) ) from tablename;

Only using @JsonIgnore during serialization, but not deserialization

You can use @JsonIgnoreProperties at class level and put variables you want to igonre in json in "value" parameter.Worked for me fine.

@JsonIgnoreProperties(value = { "myVariable1","myVariable2" })
public class MyClass {
      private int myVariable1;,
      private int myVariable2;
}

How do I add records to a DataGridView in VB.Net?

If you want to add the row to the end of the grid use the Add() method of the Rows collection...

DataGridView1.Rows.Add(New String(){Value1, Value2, Value3})

If you want to insert the row at a partiular position use the Insert() method of the Rows collection (as GWLlosa also said)...

DataGridView1.Rows.Insert(rowPosition, New String(){value1, value2, value3})

I know you mentioned you weren't doing databinding, but if you defined a strongly-typed dataset with a single datatable in your project, you could use that and get some nice strongly typed methods to do this stuff rather than rely on the grid methods...

DataSet1.DataTable.AddRow(1, "John Doe", true)

How to get Enum Value from index in Java?

I recently had the same problem and used the solution provided by Harry Joy. That solution only works with with zero-based enumaration though. I also wouldn't consider it save as it doesn't deal with indexes that are out of range.

The solution I ended up using might not be as simple but it's completely save and won't hurt the performance of your code even with big enums:

public enum Example {

    UNKNOWN(0, "unknown"), ENUM1(1, "enum1"), ENUM2(2, "enum2"), ENUM3(3, "enum3");

    private static HashMap<Integer, Example> enumById = new HashMap<>();
    static {
        Arrays.stream(values()).forEach(e -> enumById.put(e.getId(), e));
    }

    public static Example getById(int id) {
        return enumById.getOrDefault(id, UNKNOWN);
    }

    private int id;
    private String description;

    private Example(int id, String description) {
        this.id = id;
        this.description= description;
    }

    public String getDescription() {
        return description;
    }

    public int getId() {
        return id;
    }
}

If you are sure that you will never be out of range with your index and you don't want to use UNKNOWN like I did above you can of course also do:

public static Example getById(int id) {
        return enumById.get(id);
}

Add multiple items to a list

Thanks to AddRange:

Example:

public class Person
{ 
    private string Name;
    private string FirstName;

    public Person(string name, string firstname) => (Name, FirstName) = (name, firstname);
}

To add multiple Person to a List<>:

List<Person> listofPersons = new List<Person>();
listofPersons.AddRange(new List<Person>
{
    new Person("John1", "Doe" ),
    new Person("John2", "Doe" ),
    new Person("John3", "Doe" ),
 });

Asp.Net MVC with Drop Down List, and SelectListItem Assistance

You have a view model to which your view is strongly typed => use strongly typed helpers:

<%= Html.DropDownListFor(
    x => x.SelectedAccountId, 
    new SelectList(Model.Accounts, "Value", "Text")
) %>

Also notice that I use a SelectList for the second argument.

And in your controller action you were returning the view model passed as argument and not the one you constructed inside the action which had the Accounts property correctly setup so this could be problematic. I've cleaned it a bit:

public ActionResult AccountTransaction()
{
    var accounts = Services.AccountServices.GetAccounts(false);
    var viewModel = new AccountTransactionView
    {
        Accounts = accounts.Select(a => new SelectListItem
        {
            Text = a.Description,
            Value = a.AccountId.ToString()
        })
    };
    return View(viewModel);
}

Change a branch name in a Git repo

Assuming you're currently on the branch you want to rename:

git branch -m newname

This is documented in the manual for git-branch, which you can view using

man git-branch

or

git help branch

Specifically, the command is

git branch (-m | -M) [<oldbranch>] <newbranch>

where the parameters are:

   <oldbranch>
       The name of an existing branch to rename.

   <newbranch>
       The new name for an existing branch. The same restrictions as for <branchname> apply.

<oldbranch> is optional, if you want to rename the current branch.

Skip Git commit hooks

Maybe (from git commit man page):

git commit --no-verify

-n  
--no-verify

This option bypasses the pre-commit and commit-msg hooks. See also githooks(5).

As commented by Blaise, -n can have a different role for certain commands.
For instance, git push -n is actually a dry-run push.
Only git push --no-verify would skip the hook.


Note: Git 2.14.x/2.15 improves the --no-verify behavior:

See commit 680ee55 (14 Aug 2017) by Kevin Willford (``).
(Merged by Junio C Hamano -- gitster -- in commit c3e034f, 23 Aug 2017)

commit: skip discarding the index if there is no pre-commit hook

"git commit" used to discard the index and re-read from the filesystem just in case the pre-commit hook has updated it in the middle; this has been optimized out when we know we do not run the pre-commit hook.


Davi Lima points out in the comments the git cherry-pick does not support --no-verify.
So if a cherry-pick triggers a pre-commit hook, you might, as in this blog post, have to comment/disable somehow that hook in order for your git cherry-pick to proceed.
The same process would be necessary in case of a git rebase --continue, after a merge conflict resolution.

HTML: can I display button text in multiple lines?

one other way to improve and style the multi-line text is

 <button>Click here to<br/> 
     <span style="color:red;">start playing</span>

   </button>

How can I check if an element exists in the visible DOM?

You could just check to see if the parentNode property is null.

That is,

if(!myElement.parentNode)
{
    // The node is NOT in the DOM
}
else
{
    // The element is in the DOM
}

How to convert BigInteger to String in java

You can also use Java's implicit conversion:

BigInteger m = new BigInteger(bytemsg); 
String mStr = "" + m;  // mStr now contains string representation of m.

Setting initial values on load with Select2 with Ajax

Ravi, for 4.0.1-rc.1:

  1. Add all <option> elements inside <select>.
  2. call $element.val(yourarray).trigger("change"); after select2 init function.

HTML:

<select name="Tags" id="Tags" class="form-control input-lg select2" multiple="multiple">
       <option value="1">tag 1</option>
       <option value="2">tag 2</option>
       <option value="3">tag 3</option>
 </select>

JS:

var $tagsControl = $("#Tags").select2({
        ajax: {
            url: '/Tags/Search',
            dataType: 'json',
            delay: 250,
            results: function (data) {
                return {
                    results: $.map(data, function (item) {
                        return {
                            text: item.text,
                            id: item.id
                        }
                    })
                };
            },
            cache: false
        },
        minimumInputLength: 2,
        maximumSelectionLength: 6
    });

    var data = [];
    var tags = $("#Tags option").each(function () {
        data.push($(this).val());
    });
    $tagsControl.val(data).trigger("change");

This issue was reported but it still opened. https://github.com/select2/select2/issues/3116#issuecomment-146568753

How can I check whether a variable is defined in Node.js?

For me, an expression like

if (typeof query !== 'undefined' && query !== null){
   // do stuff
}

is more complicated than I want for how often I want to use it. That is, testing if a variable is defined/null is something I do frequently. I want such a test to be simple. To resolve this, I first tried to define the above code as a function, but node just gives me a syntax error, telling me the parameter to the function call is undefined. Not useful! So, searching about and working on this bit, I found a solution. Not for everyone perhaps. My solution involves using Sweet.js to define a macro. Here's how I did it:

Here's the macro (filename: macro.sjs):

// I had to install sweet using:
// npm install --save-dev
// See: https://www.npmjs.com/package/sweetbuild
// Followed instructions from https://github.com/mozilla/sweet.js/wiki/node-loader

// Initially I just had "($x)" in the macro below. But this failed to match with 
// expressions such as "self.x. Adding the :expr qualifier cures things. See
// http://jlongster.com/Writing-Your-First-Sweet.js-Macro

macro isDefined {
  rule {
    ($x:expr)
  } => {
    (( typeof ($x) === 'undefined' || ($x) === null) ? false : true)
  }
}


// Seems the macros have to be exported
// https://github.com/mozilla/sweet.js/wiki/modules

export isDefined;

Here's an example of usage of the macro (in example.sjs):

function Foobar() {
    var self = this;

    self.x = 10;

    console.log(isDefined(y)); // false
    console.log(isDefined(self.x)); // true
}

module.exports = Foobar;

And here's the main node file:

var sweet = require('sweet.js');

// load all exported macros in `macros.sjs`
sweet.loadMacro('./macro.sjs');

// example.sjs uses macros that have been defined and exported in `macros.sjs`
var Foobar = require('./example.sjs');

var x = new Foobar();

A downside of this, aside from having to install Sweet, setup the macro, and load Sweet in your code, is that it can complicate error reporting in Node. It adds a second layer of parsing. Haven't worked with this much yet, so shall see how it goes first hand. I like Sweet though and I miss macros so will try to stick with it!

How do you push a tag to a remote repository using Git?

To push a single tag:

git push origin <tag_name>

And the following command should push all tags (not recommended):

git push --tags

Rotating a Vector in 3D Space

If you want to rotate a vector you should construct what is known as a rotation matrix.

Rotation in 2D

Say you want to rotate a vector or a point by ?, then trigonometry states that the new coordinates are

    x' = x cos ? - y sin ?
    y' = x sin ? + y cos ?

To demo this, let's take the cardinal axes X and Y; when we rotate the X-axis 90° counter-clockwise, we should end up with the X-axis transformed into Y-axis. Consider

    Unit vector along X axis = <1, 0>
    x' = 1 cos 90 - 0 sin 90 = 0
    y' = 1 sin 90 + 0 cos 90 = 1
    New coordinates of the vector, <x', y'> = <0, 1>  ?  Y-axis

When you understand this, creating a matrix to do this becomes simple. A matrix is just a mathematical tool to perform this in a comfortable, generalized manner so that various transformations like rotation, scale and translation (moving) can be combined and performed in a single step, using one common method. From linear algebra, to rotate a point or vector in 2D, the matrix to be built is

    |cos ?   -sin ?| |x| = |x cos ? - y sin ?| = |x'|
    |sin ?    cos ?| |y|   |x sin ? + y cos ?|   |y'|

Rotation in 3D

That works in 2D, while in 3D we need to take in to account the third axis. Rotating a vector around the origin (a point) in 2D simply means rotating it around the Z-axis (a line) in 3D; since we're rotating around Z-axis, its coordinate should be kept constant i.e. 0° (rotation happens on the XY plane in 3D). In 3D rotating around the Z-axis would be

    |cos ?   -sin ?   0| |x|   |x cos ? - y sin ?|   |x'|
    |sin ?    cos ?   0| |y| = |x sin ? + y cos ?| = |y'|
    |  0       0      1| |z|   |        z        |   |z'|

around the Y-axis would be

    | cos ?    0   sin ?| |x|   | x cos ? + z sin ?|   |x'|
    |   0      1       0| |y| = |         y        | = |y'|
    |-sin ?    0   cos ?| |z|   |-x sin ? + z cos ?|   |z'|

around the X-axis would be

    |1     0           0| |x|   |        x        |   |x'|
    |0   cos ?    -sin ?| |y| = |y cos ? - z sin ?| = |y'|
    |0   sin ?     cos ?| |z|   |y sin ? + z cos ?|   |z'|

Note 1: axis around which rotation is done has no sine or cosine elements in the matrix.

Note 2: This method of performing rotations follows the Euler angle rotation system, which is simple to teach and easy to grasp. This works perfectly fine for 2D and for simple 3D cases; but when rotation needs to be performed around all three axes at the same time then Euler angles may not be sufficient due to an inherent deficiency in this system which manifests itself as Gimbal lock. People resort to Quaternions in such situations, which is more advanced than this but doesn't suffer from Gimbal locks when used correctly.

I hope this clarifies basic rotation.

Rotation not Revolution

The aforementioned matrices rotate an object at a distance r = v(x² + y²) from the origin along a circle of radius r; lookup polar coordinates to know why. This rotation will be with respect to the world space origin a.k.a revolution. Usually we need to rotate an object around its own frame/pivot and not around the world's i.e. local origin. This can also be seen as a special case where r = 0. Since not all objects are at the world origin, simply rotating using these matrices will not give the desired result of rotating around the object's own frame. You'd first translate (move) the object to world origin (so that the object's origin would align with the world's, thereby making r = 0), perform the rotation with one (or more) of these matrices and then translate it back again to its previous location. The order in which the transforms are applied matters. Combining multiple transforms together is called concatenation or composition.

Composition

I urge you to read about linear and affine transformations and their composition to perform multiple transformations in one shot, before playing with transformations in code. Without understanding the basic maths behind it, debugging transformations would be a nightmare. I found this lecture video to be a very good resource. Another resource is this tutorial on transformations that aims to be intuitive and illustrates the ideas with animation (caveat: authored by me!).

Rotation around Arbitrary Vector

A product of the aforementioned matrices should be enough if you only need rotations around cardinal axes (X, Y or Z) like in the question posted. However, in many situations you might want to rotate around an arbitrary axis/vector. The Rodrigues' formula (a.k.a. axis-angle formula) is a commonly prescribed solution to this problem. However, resort to it only if you’re stuck with just vectors and matrices. If you're using Quaternions, just build a quaternion with the required vector and angle. Quaternions are a superior alternative for storing and manipulating 3D rotations; it's compact and fast e.g. concatenating two rotations in axis-angle representation is fairly expensive, moderate with matrices but cheap in quaternions. Usually all rotation manipulations are done with quaternions and as the last step converted to matrices when uploading to the rendering pipeline. See Understanding Quaternions for a decent primer on quaternions.

"Comparison method violates its general contract!"

Editing VM Configuration worked for me.

-Djava.util.Arrays.useLegacyMergeSort=true

Display only date and no time

Just had to deal with this scenario myself - found a really easy way to do this, simply annotate your property in the model like this:

[DataType(DataType.Date)]
public DateTime? SomeDateProperty { get; set; }

It will hide the time button from the date picker too.

Sorry if this answer is a little late ;)

Set bootstrap modal body height by percentage

Instead of using a %, the units vh set it to a percent of the viewport (browser window) size.

I was able to set a modal with an image and text beneath to be responsive to the browser window size using vh.

If you just want the content to scroll, you could leave out the part that limits the size of the modal body.

/*When the modal fills the screen it has an even 2.5% on top and bottom*/
/*Centers the modal*/
.modal-dialog {
  margin: 2.5vh auto;
}

/*Sets the maximum height of the entire modal to 95% of the screen height*/
.modal-content {
  max-height: 95vh;
  overflow: scroll;
}

/*Sets the maximum height of the modal body to 90% of the screen height*/
.modal-body {
  max-height: 90vh;
}
/*Sets the maximum height of the modal image to 69% of the screen height*/
.modal-body img {
  max-height: 69vh;
}

How can I check if a string is a number?

Use Int32.TryParse()

int num;

bool isNum = Int32.TryParse("[string to test]", out num);

if (isNum)
{
    //Is a Number
}
else
{
    //Not a number
}

MSDN Reference

How to get the size of the current screen in WPF?

If you are familiar with using System.Windows.Forms class then you can just add a reference of System.Windows.Forms class to your project:

Solution Explorer -> References -> Add References... -> ( Assemblies : Framework ) -> scroll down and check System.Windows.Forms assembly -> OK.

Now you can add using System.Windows.Forms; statement and use screen in your wpf project just like before.

jQuery location href

You can use just JavaScript:

window.location = 'http://address.com';

Best way to get application folder path

In my experience, the best way is a combination of these.

  1. System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase Will give you the bin folder
  2. Directory.GetCurrentDirectory() Works fine on .Net Core but not .Net and will give you the root directory of the project
  3. System.AppContext.BaseDirectory and AppDomain.CurrentDomain.BaseDirectory Works fine in .Net but not .Net core and will give you the root directory of the project

In a class library that is supposed to target.Net and .Net core I check which framework is hosting the library and pick one or the other.

How to write multiple line string using Bash with variables?

I'm using Mac OS and to write multiple lines in a SH Script following code worked for me

#! /bin/bash
FILE_NAME="SomeRandomFile"

touch $FILE_NAME

echo """I wrote all
the  
stuff
here.
And to access a variable we can use
$FILE_NAME  

""" >> $FILE_NAME

cat $FILE_NAME

Please don't forget to assign chmod as required to the script file. I have used

chmod u+x myScriptFile.sh

Setting the default Java character encoding

I think a better approach than setting the platform's default character set, especially as you seem to have restrictions on affecting the application deployment, let alone the platform, is to call the much safer String.getBytes("charsetName"). That way your application is not dependent on things beyond its control.

I personally feel that String.getBytes() should be deprecated, as it has caused serious problems in a number of cases I have seen, where the developer did not account for the default charset possibly changing.

How to push to History in React Router v4?

/*Step 1*/
myFunction(){  this.props.history.push("/home"); }
/**/
 <button onClick={()=>this.myFunction()} className={'btn btn-primary'}>Go 
 Home</button>

How can I check if a command exists in a shell script?

which <cmd>

also see options which supports for aliases if applicable to your case.

Example

$ which foobar
which: no foobar in (/usr/local/bin:/usr/bin:/cygdrive/c/Program Files (x86)/PC Connectivity Solution:/cygdrive/c/Windows/system32/System32/WindowsPowerShell/v1.0:/cygdrive/d/Program Files (x86)/Graphviz 2.28/bin:/cygdrive/d/Program Files (x86)/GNU/GnuPG
$ if [ $? -eq 0 ]; then echo "foobar is found in PATH"; else echo "foobar is NOT found in PATH, of course it does not mean it is not installed."; fi
foobar is NOT found in PATH, of course it does not mean it is not installed.
$

PS: Note that not everything that's installed may be in PATH. Usually to check whether something is "installed" or not one would use installation related commands relevant to the OS. E.g. rpm -qa | grep -i "foobar" for RHEL.

mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc... expects parameter 1 to be resource

since $username is a php variable we need to pass it as string to mysqli so since in the query u started with a single quote we will use the double quote, single quote and a fullstop for the concatination purposes ("'.$username.'") if you started with a double quote you would then reverse the quotes ('".$username."').

$username = $_POST['username'];
$password = $_POST['password'];
$result = mysql_query('SELECT * FROM Users WHERE UserName LIKE "'.$username.'"');

while($row = mysql_fetch_array($result))
     {
      echo $row['FirstName'];
     }

$username = $_POST['username'];
$password = $_POST['password'];
$result = mysql_query("SELECT * FROM Users WHERE UserName LIKE '".$username."' ");

while($row = mysql_fetch_array($result))
     {
      echo $row['FirstName'];
     }

but use of Mysql has depreciated much, use PDO instead.it is simple but very secure

How to compare two Dates without the time portion?

If you strictly want to use Date ( java.util.Date ), or without any use of external Library. Use this :

public Boolean compareDateWithoutTime(Date d1, Date d2) {
    SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
    return sdf.format(d1).equals(sdf.format(d2));
}

How can I pad an integer with zeros on the left?

Found this example... Will test...

import java.text.DecimalFormat;
class TestingAndQualityAssuranceDepartment
{
    public static void main(String [] args)
    {
        int x=1;
        DecimalFormat df = new DecimalFormat("00");
        System.out.println(df.format(x));
    }
}

Tested this and:

String.format("%05d",number);

Both work, for my purposes I think String.Format is better and more succinct.

Java ArrayList replace at specific index

Lets get array list as ArrayList and new value as value all you need to do is pass the parameters to .set method. ArrayList.set(index,value)

Ex -

ArrayList.set(10,"new value or object")

Convert file: Uri to File in Android

Extension base on @Jacek Kwiecien answer for convert image uri to file

fun Uri.toImageFile(context: Context): File? {
    val filePathColumn = arrayOf(MediaStore.Images.Media.DATA)
    val cursor = context.contentResolver.query(this, filePathColumn, null, null, null)
    if (cursor != null) {
        if (cursor.moveToFirst()) {
            val columnIndex = cursor.getColumnIndex(filePathColumn[0])
            val filePath = cursor.getString(columnIndex)
            cursor.close()
            return File(filePath)
        }
        cursor.close()
    }
    return null
}

If we use File(uri.getPath()), it will not work

enter image description here

If we use extension from android-ktx, it still not work too because https://github.com/android/android-ktx/blob/master/src/main/java/androidx/core/net/Uri.kt

What is "stdafx.h" used for in Visual Studio?

All C++ compilers have one serious performance problem to deal with. Compiling C++ code is a long, slow process.

Compiling headers included on top of C++ files is a very long, slow process. Compiling the huge header structures that form part of Windows API and other large API libraries is a very, very long, slow process. To have to do it over, and over, and over for every single Cpp source file is a death knell.

This is not unique to Windows but an old problem faced by all compilers that have to compile against a large API like Windows.

The Microsoft compiler can ameliorate this problem with a simple trick called precompiled headers. The trick is pretty slick: although every CPP file can potentially and legally give a sligthly different meaning to the chain of header files included on top of each Cpp file (by things like having different macros #define'd in advance of the includes, or by including the headers in different order), that is most often not the case. Most of the time, we have dozens or hundreds of included files, but they all are intended to have the same meaning for all the Cpp files being compiled in your application.

The compiler can make huge time savings if it doesn't have to start to compile every Cpp file plus its dozens of includes literally from scratch every time.

The trick consists of designating a special header file as the starting point of all compilation chains, the so called 'precompiled header' file, which is commonly a file named stdafx.h simply for historical reasons.

Simply list all your big huge headers for your APIs in your stdafx.h file, in the appropriate order, and then start each of your CPP files at the very top with an #include "stdafx.h", before any meaningful content (just about the only thing allowed before is comments).

Under those conditions, instead of starting from scratch, the compiler starts compiling from the already saved results of compiling everything in stdafx.h.

I don't believe that this trick is unique to Microsoft compilers, nor do I think it was an original development.

For Microsoft compilers, the setting that controls the use of precompiled headers is controlled by a command line argument to the compiler: /Yu "stdafx.h". As you can imagine, the use of the stdafx.h file name is simply a convention; you can change the name if you so wish.

In Visual Studio 2010, this setting is controlled from the GUI via Right-clicking on a CPP Project, selecting 'Properties' and navigating to "Configuration Properties\C/C++\Precompiled Headers". For other versions of Visual Studio, the location in the GUI will be different.

Note that if you disable precompiled headers (or run your project through a tool that doesn't support them), it doesn't make your program illegal; it simply means that your tool will compile everything from scratch every time.

If you are creating a library with no Windows dependencies, you can easily comment out or remove #includes from the stdafx.h file. There is no need to remove the file per se, but clearly you may do so as well, by disabling the precompile header setting above.

Returning JSON response from Servlet to Javascript/JSP page

I used JSONObject as shown below in Servlet.

    JSONObject jsonReturn = new JSONObject();

    NhAdminTree = AdminTasks.GetNeighborhoodTreeForNhAdministrator( connection, bwcon, userName);

    map = new HashMap<String, String>();
    map.put("Status", "Success");
    map.put("FailureReason", "None");
    map.put("DataElements", "2");

    jsonReturn = new JSONObject();
    jsonReturn.accumulate("Header", map);

    List<String> list = new ArrayList<String>();
    list.add(NhAdminTree);
    list.add(userName);

    jsonReturn.accumulate("Elements", list);

The Servlet returns this JSON object as shown below:

    response.setContentType("application/json");
    response.getWriter().write(jsonReturn.toString());

This Servlet is called from Browser using AngularJs as below

$scope.GetNeighborhoodTreeUsingPost = function(){
    alert("Clicked GetNeighborhoodTreeUsingPost : " + $scope.userName );

    $http({

        method: 'POST',
        url : 'http://localhost:8080/EPortal/xlEPortalService',
        headers: {
           'Content-Type': 'application/json'
         },
        data : {
            'action': 64,
            'userName' : $scope.userName
        }
    }).success(function(data, status, headers, config){
        alert("DATA.header.status : " + data.Header.Status);
        alert("DATA.header.FailureReason : " + data.Header.FailureReason);
        alert("DATA.header.DataElements : " + data.Header.DataElements);
        alert("DATA.elements : " + data.Elements);

    }).error(function(data, status, headers, config) {
        alert(data + " : " + status + " : " + headers + " : " + config);
    });

};

This code worked and it is showing correct data in alert dialog box:

Data.header.status : Success

Data.header.FailureReason : None

Data.header.DetailElements : 2

Data.Elements : Coma seperated string values i.e. NhAdminTree, userName

How to get array keys in Javascript?

The question is pretty old, but nowadays you can use forEach, which is efficient and will retain the keys as numbers:

let keys = widthRange.map((v,k) => k).filter(i=>i!==undefined))

This loops through widthRange and makes a new array with the value of the keys, and then filters out all sparce slots by only taking the values that are defined.

(Bad idea, but for thorughness: If slot 0 was always empty, that could be shortened to filter(i=>i) or filter(Boolean)

And, it may be less efficient, but the numbers can be cast with let keys = Object.keys(array).map(i=>i*1)

How can I directly view blobs in MySQL Workbench

there is few things that you can do

SELECT GROUP_CONCAT(CAST(name AS CHAR))
FROM product
WHERE  id   IN (12345,12346,12347)

If you want to order by the query you can order by cast as well like below

SELECT GROUP_CONCAT(name ORDER BY name))
FROM product
WHERE id   IN (12345,12346,12347)

as it says on this blog

http://www.kdecom.com/mysql-group-concat-blob-bug-solved/

JSON formatter in C#?

This is a variant of the accepted answer that I like to use. The commented parts result in what I consider a more readable format (you would need to comment out the adjacent code to see the difference):

public class JsonHelper
{
    private const int INDENT_SIZE = 4;

    public static string FormatJson(string str)
    {
        str = (str ?? "").Replace("{}", @"\{\}").Replace("[]", @"\[\]");

        var inserts = new List<int[]>();
        bool quoted = false, escape = false;
        int depth = 0/*-1*/;

        for (int i = 0, N = str.Length; i < N; i++)
        {
            var chr = str[i];

            if (!escape && !quoted)
                switch (chr)
                {
                    case '{':
                    case '[':
                        inserts.Add(new[] { i, +1, 0, INDENT_SIZE * ++depth });
                        //int n = (i == 0 || "{[,".Contains(str[i - 1])) ? 0 : -1;
                        //inserts.Add(new[] { i, n, INDENT_SIZE * ++depth * -n, INDENT_SIZE - 1 });
                        break;
                    case ',':
                        inserts.Add(new[] { i, +1, 0, INDENT_SIZE * depth });
                        //inserts.Add(new[] { i, -1, INDENT_SIZE * depth, INDENT_SIZE - 1 });
                        break;
                    case '}':
                    case ']':
                        inserts.Add(new[] { i, -1, INDENT_SIZE * --depth, 0 });
                        //inserts.Add(new[] { i, -1, INDENT_SIZE * depth--, 0 });
                        break;
                    case ':':
                        inserts.Add(new[] { i, 0, 1, 1 });
                        break;
                }

            quoted = (chr == '"') ? !quoted : quoted;
            escape = (chr == '\\') ? !escape : false;
        }

        if (inserts.Count > 0)
        {
            var sb = new System.Text.StringBuilder(str.Length * 2);

            int lastIndex = 0;
            foreach (var insert in inserts)
            {
                int index = insert[0], before = insert[2], after = insert[3];
                bool nlBefore = (insert[1] == -1), nlAfter = (insert[1] == +1);

                sb.Append(str.Substring(lastIndex, index - lastIndex));

                if (nlBefore) sb.AppendLine();
                if (before > 0) sb.Append(new String(' ', before));

                sb.Append(str[index]);

                if (nlAfter) sb.AppendLine();
                if (after > 0) sb.Append(new String(' ', after));

                lastIndex = index + 1;
            }

            str = sb.ToString();
        }

        return str.Replace(@"\{\}", "{}").Replace(@"\[\]", "[]");
    }
}

When should the xlsm or xlsb formats be used?

The XLSB format is also dedicated to the macros embeded in an hidden workbook file located in excel startup folder (XLSTART).

A quick & dirty test with a xlsm or xlsb in XLSTART folder:

Measure-Command { $x = New-Object -com Excel.Application ;$x.Visible = $True ; $x.Quit() }

0,89s with a xlsb (binary) versus 1,3s with the same content in xlsm format (xml in a zip file) ... :)

How to hide element using Twitter Bootstrap and show it using jQuery?

The right answer

Bootstrap 4.x

Bootstrap 4.x uses the new .d-none class. Instead of using either .hidden, or .hide if you're using Bootstrap 4.x use .d-none.

<div id="myId" class="d-none">Foobar</div>
  • To show it: $("#myId").removeClass('d-none');
  • To hide it: $("#myId").addClass('d-none');
  • To toggle it: $("#myId").toggleClass('d-none');

(thanks to the comment by Fangming)

Bootstrap 3.x

First, don't use .hide! Use .hidden. As others have said, .hide is deprecated,

.hide is available, but it does not always affect screen readers and is deprecated as of v3.0.1

Second, use jQuery's .toggleClass(), .addClass() and .removeClass()

<div id="myId" class="hidden">Foobar</div>
  • To show it: $("#myId").removeClass('hidden');
  • To hide it: $("#myId").addClass('hidden');
  • To toggle it: $("#myId").toggleClass('hidden');

Don't use the css class .show, it has a very small use case. The definitions of show, hidden and invisible are in the docs.

// Classes
.show {
  display: block !important;
}
.hidden {
  display: none !important;
  visibility: hidden !important;
}
.invisible {
  visibility: hidden;
}

Send values from one form to another form

// In form 1
public static string Username = Me;

// In form 2's load block
string _UserName = Form1.Username;

ImportError: No module named pandas

I fixed the same problem with the below commands... Type python on your terminal. If you see python version 2.x then run these two commands to install pandas:

sudo python -m pip install wheel

and

sudo python -m pip install pandas

Else if you see python version 3.x then run these two commands to install pandas:

sudo python3 -m pip install wheel

and

sudo python3 -m pip install pandas

Good Luck!

Selecting multiple columns in a Pandas dataframe

In the latest version of Pandas there is an easy way to do exactly this. Column names (which are strings) can be sliced in whatever manner you like.

columns = ['b', 'c']
df1 = pd.DataFrame(df, columns=columns)

How to capture the browser window close event?

My answer is aimed at providing simple benchmarks.

HOW TO

See @SLaks answer.

$(window).on("beforeunload", function() { 
    return inFormOrLink ? "Do you really want to close?" : null; 
})

How long does the browser take to finally shut your page down?

Whenever an user closes the page (x button or CTRL + W), the browser executes the given beforeunload code, but not indefinitely. The only exception is the confirmation box (return 'Do you really want to close?) which will wait until for the user's response.

Chrome: 2 seconds.
Firefox: 8 (or double click, or force on close)
Edge: 8 (or double click)
Explorer 11: 0 seconds.
Safari: TODO

What we used to test this out:

  • A Node.js Express server with requests log
  • The following short HTML file

What it does is to send as many requests as it can before the browser shut downs its page (synchronously).

<html>
<body>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>
    <script>
    function request() {
        return $.ajax({
            type: "GET",
            url: "http://localhost:3030/" + Date.now(),
            async: true
        }).responseText;
    }
    window.onbeforeunload = () => {
        while (true) {
            request();
        }
        return null;
    }
    </script>
</body>
</html>

Chrome output:

GET /1480451321041 404 0.389 ms - 32  
GET /1480451321052 404 0.219 ms - 32  
...  
GET /hello/1480451322998 404 0.328 ms - 32

1957ms ˜ 2 seconds // we assume it's 2 seconds since requests can take few milliseconds to be sent.

How to sort rows of HTML table that are called from MySQL

A SIMPLE TABLE SORT PHP CODE:

(the simple table for several values processing and sorting, using this sortable.js script )

<html><head>
<script src="sorttable.js"></script>

<style>
tbody tr td {color:green;border-right:1px solid;width:200px;}
</style>
</head><body>

<?php
$First = array('a', 'b', 'c', 'd');
$Second = array('1', '2', '3', '4');

if (!empty($_POST['myFirstvalues'])) 
{ $First = explode("\r\n",$_POST['myFirstvalues']); $Second = explode("\r\n",$_POST['mySecondvalues']);}

?>

</br>Hi User. PUT your values</br></br>
<form action="" method="POST">
projectX</br>
<textarea cols="20" rows="20" name="myFirstvalues" style="width:200px;background:url(untitled.PNG);position:relative;top:19px;Float:left;">
<?php foreach($First as $vv) {echo $vv."\r\n";}?>
</textarea>

The due amount</br>
<textarea cols="20" rows="20" name="mySecondvalues" style="width:200px;background:url(untitled.PNG);Float:left;">
<?php foreach($Second as $vv) {echo $vv."\r\n";}?>
</textarea>
<input type="submit">
</form>

<table class="sortable" style="padding:100px 0 0 300px;">
<thead style="background-color:#999999; color:red; font-weight: bold; cursor: default;  position:relative;">
  <tr><th>ProjectX</th><th>Due amount</th></tr>
</thead>
<tbody>

<?php
foreach($First as $indx => $value) {
    echo '<tr><td>'.$First[$indx].'</td><td>'.$Second[$indx].'</td></tr>';
}
?>
</tbody>
<tfoot><tr><td>TOTAL  = &nbsp;<b>111111111</b></td><td>Still to spend  = &nbsp;<b>5555555</b></td></tr></tfoot></br></br>
</table>
</body>
</html>

source: php sortable table

Why is a ConcurrentModificationException thrown and how to debug it

Modification of a Collection while iterating through that Collection using an Iterator is not permitted by most of the Collection classes. The Java library calls an attempt to modify a Collection while iterating through it a "concurrent modification". That unfortunately suggests the only possible cause is simultaneous modification by multiple threads, but that is not so. Using only one thread it is possible to create an iterator for the Collection (using Collection.iterator(), or an enhanced for loop), start iterating (using Iterator.next(), or equivalently entering the body of the enhanced for loop), modify the Collection, then continue iterating.

To help programmers, some implementations of those Collection classes attempt to detect erroneous concurrent modification, and throw a ConcurrentModificationException if they detect it. However, it is in general not possible and practical to guarantee detection of all concurrent modifications. So erroneous use of the Collection does not always result in a thrown ConcurrentModificationException.

The documentation of ConcurrentModificationException says:

This exception may be thrown by methods that have detected concurrent modification of an object when such modification is not permissible...

Note that this exception does not always indicate that an object has been concurrently modified by a different thread. If a single thread issues a sequence of method invocations that violates the contract of an object, the object may throw this exception...

Note that fail-fast behavior cannot be guaranteed as it is, generally speaking, impossible to make any hard guarantees in the presence of unsynchronized concurrent modification. Fail-fast operations throw ConcurrentModificationException on a best-effort basis.

Note that

The documentation of the HashSet, HashMap, TreeSet and ArrayList classes says this:

The iterators returned [directly or indirectly from this class] are fail-fast: if the [collection] is modified at any time after the iterator is created, in any way except through the iterator's own remove method, the Iterator throws a ConcurrentModificationException. Thus, in the face of concurrent modification, the iterator fails quickly and cleanly, rather than risking arbitrary, non-deterministic behavior at an undetermined time in the future.

Note that the fail-fast behavior of an iterator cannot be guaranteed as it is, generally speaking, impossible to make any hard guarantees in the presence of unsynchronized concurrent modification. Fail-fast iterators throw ConcurrentModificationException on a best-effort basis. Therefore, it would be wrong to write a program that depended on this exception for its correctness: the fail-fast behavior of iterators should be used only to detect bugs.

Note again that the behaviour "cannot be guaranteed" and is only "on a best-effort basis".

The documentation of several methods of the Map interface say this:

Non-concurrent implementations should override this method and, on a best-effort basis, throw a ConcurrentModificationException if it is detected that the mapping function modifies this map during computation. Concurrent implementations should override this method and, on a best-effort basis, throw an IllegalStateException if it is detected that the mapping function modifies this map during computation and as a result computation would never complete.

Note again that only a "best-effort basis" is required for detection, and a ConcurrentModificationException is explicitly suggested only for the non concurrent (non thread-safe) classes.

Debugging ConcurrentModificationException

So, when you see a stack-trace due to a ConcurrentModificationException, you can not immediately assume that the cause is unsafe multi-threaded access to a Collection. You must examine the stack-trace to determine which class of Collection threw the exception (a method of the class will have directly or indirectly thrown it), and for which Collection object. Then you must examine from where that object can be modified.

  • The most common cause is modification of the Collection within an enhanced for loop over the Collection. Just because you do not see an Iterator object in your source code does not mean there is no Iterator there! Fortunately, one of the statements of the faulty for loop will usually be in the stack-trace, so tracking down the error is usually easy.
  • A trickier case is when your code passes around references to the Collection object. Note that unmodifiable views of collections (such as produced by Collections.unmodifiableList()) retain a reference to the modifiable collection, so iteration over an "unmodifiable" collection can throw the exception (the modification has been done elsewhere). Other views of your Collection, such as sub lists, Map entry sets and Map key sets also retain references to the original (modifiable) Collection. This can be a problem even for a thread-safe Collection, such as CopyOnWriteList; do not assume that thread-safe (concurrent) collections can never throw the exception.
  • Which operations can modify a Collection can be unexpected in some cases. For example, LinkedHashMap.get() modifies its collection.
  • The hardest cases are when the exception is due to concurrent modification by multiple threads.

Programming to prevent concurrent modification errors

When possible, confine all references to a Collection object, so its is easier to prevent concurrent modifications. Make the Collection a private object or a local variable, and do not return references to the Collection or its iterators from methods. It is then much easier to examine all the places where the Collection can be modified. If the Collection is to be used by multiple threads, it is then practical to ensure that the threads access the Collection only with appropriate synchonization and locking.

Using DISTINCT and COUNT together in a MySQL Query

I would do something like this:

Select count(*), productid
from products
where keyword = '$keyword'
group by productid

that will give you a list like

count(*)    productid  
----------------------
 5           12345   
 3           93884   
 9           93493    

This allows you to see how many of each distinct productid ID is associated with the keyword.

Make Font Awesome icons in a circle?

UPDATE:

Upon learning flex recently, there is a cleaner way (no tables and less css). Set the wrapper as display: flex; and to center it's children give it the properties align-items: center; for (vertical) and justify-content: center; (horizontal) centering.

See this updated JS Fiddle


Strange that nobody suggested this before.. I always use tables to do this.
Simply make a wrapper have display: table and center stuff inside it with text-align: center for horizontal and vertical-align: middle for vertical alignment.

<div class='wrapper'>
  <i class='icon fa fa-bars'></i>
</div>

and some sass like this

.wrapper{
  display: table; 

  i{
    display: table-cell;
    vertical-align: middle;
    text-align: center;
  }

}

or see this JS Fiddle

What is the difference between ELF files and bin files?

A Bin file is a pure binary file with no memory fix-ups or relocations, more than likely it has explicit instructions to be loaded at a specific memory address. Whereas....

ELF files are Executable Linkable Format which consists of a symbol look-ups and relocatable table, that is, it can be loaded at any memory address by the kernel and automatically, all symbols used, are adjusted to the offset from that memory address where it was loaded into. Usually ELF files have a number of sections, such as 'data', 'text', 'bss', to name but a few...it is within those sections where the run-time can calculate where to adjust the symbol's memory references dynamically at run-time.

Actionbar notification count icon (badge) like Google has

I found a very good solution here, I'm using it with kotlin.

First, in the drawable folder you have to create item_count.xml:

<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<corners android:radius="8dp" />
<solid android:color="#f20000" />
<stroke
    android:width="2dip"
    android:color="#FFF" />
<padding
    android:bottom="5dp"
    android:left="5dp"
    android:right="5dp"
    android:top="5dp" />
</shape>

In your Activity_Main Layout some like:

<RelativeLayout
                    android:id="@+id/badgeLayout"
                    android:layout_width="40dp"
                    android:layout_height="40dp"
                    android:layout_toRightOf="@+id/badge_layout1"
                    android:layout_gravity="end|center_vertical"
                    android:layout_marginEnd="5dp">

                <RelativeLayout
                        android:id="@+id/relative_layout1"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content">

                    <Button
                            android:id="@+id/btnBadge"
                            android:layout_width="match_parent"
                            android:layout_height="match_parent"
                            android:background="@mipmap/ic_notification" />

                </RelativeLayout>

                <TextView
                        android:id="@+id/txtBadge"
                        android:layout_width="18dp"
                        android:layout_height="18dp"
                        android:layout_alignRight="@id/relative_layout1"
                        android:background="@drawable/item_count"
                        android:text="22"
                        android:textColor="#FFF"
                        android:textSize="7sp"
                        android:textStyle="bold"
                        android:gravity="center"/>

            </RelativeLayout>

And you can modify like:

btnBadge.setOnClickListener { view ->
        Snackbar.make(view,"badge click", Snackbar.LENGTH_LONG) .setAction("Action", null).show()
        txtBadge.text = "0"
    }

Ruby Hash to array of values

I would use:

hash.map { |key, value| value }

How do I generate a constructor from class fields using Visual Studio (and/or ReSharper)?

In Visual Studio click on one of the fields -> click the light bulb -> Generate Constructors -> Select the fields

SQL MAX of multiple columns?

I prefer solutions based on case-when, my assumption is that it should have the least impact on possible performance drop compared to other possible solutions like those with cross-apply, values(), custom functions etc.

Here is the case-when version that handles null values with most of possible test cases:

SELECT
    CASE 
        WHEN Date1 > coalesce(Date2,'0001-01-01') AND Date1 > coalesce(Date3,'0001-01-01') THEN Date1 
        WHEN Date2 > coalesce(Date3,'0001-01-01') THEN Date2 
        ELSE Date3
    END AS MostRecentDate
    , *
from 
(values
     (  1, cast('2001-01-01' as Date), cast('2002-01-01' as Date), cast('2003-01-01' as Date))
    ,(  2, cast('2001-01-01' as Date), cast('2003-01-01' as Date), cast('2002-01-01' as Date))
    ,(  3, cast('2002-01-01' as Date), cast('2001-01-01' as Date), cast('2003-01-01' as Date))
    ,(  4, cast('2002-01-01' as Date), cast('2003-01-01' as Date), cast('2001-01-01' as Date))
    ,(  5, cast('2003-01-01' as Date), cast('2001-01-01' as Date), cast('2002-01-01' as Date))
    ,(  6, cast('2003-01-01' as Date), cast('2002-01-01' as Date), cast('2001-01-01' as Date))
    ,( 11, cast(NULL         as Date), cast('2002-01-01' as Date), cast('2003-01-01' as Date))
    ,( 12, cast(NULL         as Date), cast('2003-01-01' as Date), cast('2002-01-01' as Date))
    ,( 13, cast('2003-01-01' as Date), cast(NULL         as Date), cast('2002-01-01' as Date))
    ,( 14, cast('2002-01-01' as Date), cast(NULL         as Date), cast('2003-01-01' as Date))
    ,( 15, cast('2003-01-01' as Date), cast('2002-01-01' as Date), cast(NULL         as Date))
    ,( 16, cast('2002-01-01' as Date), cast('2003-01-01' as Date), cast(NULL         as Date))
    ,( 21, cast('2003-01-01' as Date), cast(NULL         as Date), cast(NULL         as Date))
    ,( 22, cast(NULL         as Date), cast('2003-01-01' as Date), cast(NULL         as Date))
    ,( 23, cast(NULL         as Date), cast(NULL         as Date), cast('2003-01-01' as Date))
    ,( 31, cast(NULL         as Date), cast(NULL         as Date), cast(NULL         as Date))

) as demoValues(id, Date1,Date2,Date3)
order by id
;

and the result is:

MostRecent    id   Date1      Date2      Date3
2003-01-01    1    2001-01-01 2002-01-01 2003-01-01
2003-01-01    2    2001-01-01 2003-01-01 2002-01-01
2003-01-01    3    2002-01-01 2001-01-01 2002-01-01
2003-01-01    4    2002-01-01 2003-01-01 2001-01-01
2003-01-01    5    2003-01-01 2001-01-01 2002-01-01
2003-01-01    6    2003-01-01 2002-01-01 2001-01-01
2003-01-01    11   NULL       2002-01-01 2003-01-01
2003-01-01    12   NULL       2003-01-01 2002-01-01
2003-01-01    13   2003-01-01 NULL       2002-01-01
2003-01-01    14   2002-01-01 NULL       2003-01-01
2003-01-01    15   2003-01-01 2002-01-01 NULL
2003-01-01    16   2002-01-01 2003-01-01 NULL
2003-01-01    21   2003-01-01 NULL       NULL
2003-01-01    22   NULL       2003-01-01 NULL
2003-01-01    23   NULL       NULL       2003-01-01
NULL          31   NULL       NULL       NULL

Sending and Receiving SMS and MMS in Android (pre Kit Kat Android 4.4)

SmsListenerClass

public class SmsListener extends BroadcastReceiver {

static final String ACTION =
        "android.provider.Telephony.SMS_RECEIVED";

@Override
public void onReceive(Context context, Intent intent) {

    Log.e("RECEIVED", ":-:-" + "SMS_ARRIVED");

    // TODO Auto-generated method stub
    if (intent.getAction().equals(ACTION)) {

        Log.e("RECEIVED", ":-" + "SMS_ARRIVED");

        StringBuilder buf = new StringBuilder();
        Bundle bundle = intent.getExtras();
        if (bundle != null) {

            Object[] pdus = (Object[]) bundle.get("pdus");

            SmsMessage[] messages = new SmsMessage[pdus.length];
            SmsMessage message = null;

            for (int i = 0; i < messages.length; i++) {

                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                    String format = bundle.getString("format");
                    messages[i] = SmsMessage.createFromPdu((byte[]) pdus[i], format);
                } else {
                    messages[i] = SmsMessage.createFromPdu((byte[]) pdus[i]);
                }

                message = messages[i];
                buf.append("Received SMS from  ");
                buf.append(message.getDisplayOriginatingAddress());
                buf.append(" - ");
                buf.append(message.getDisplayMessageBody());
            }

            MainActivity inst = MainActivity.instance();
            inst.updateList(message.getDisplayOriginatingAddress(),message.getDisplayMessageBody());

        }

        Log.e("RECEIVED:", ":" + buf.toString());

        Toast.makeText(context, "RECEIVED SMS FROM :" + buf.toString(), Toast.LENGTH_LONG).show();

    }
}

Activity

@Override
public void onStart() {
    super.onStart();
    inst = this;
}

public static MainActivity instance() {
    return inst;
}

public void updateList(final String msg_from, String msg_body) {

    tvMessage.setText(msg_from + " :- " + msg_body);

    sendSMSMessage(msg_from, msg_body);

}

protected void sendSMSMessage(String phoneNo, String message) {

    try {
        SmsManager smsManager = SmsManager.getDefault();
        smsManager.sendTextMessage(phoneNo, null, message, null, null);
        Toast.makeText(getApplicationContext(), "SMS sent.", Toast.LENGTH_LONG).show();
    } catch (Exception e) {
        Toast.makeText(getApplicationContext(), "SMS faild, please try again.", Toast.LENGTH_LONG).show();
        e.printStackTrace();
    }
}

Manifest

<uses-permission android:name="android.permission.RECEIVE_SMS"/>
<uses-permission android:name="android.permission.READ_SMS" />
<uses-permission android:name="android.permission.SEND_SMS"/>

<receiver android:name=".SmsListener">
        <intent-filter>
            <action android:name="android.provider.Telephony.SMS_RECEIVED" />
        </intent-filter>
    </receiver>

How to execute two mysql queries as one in PHP/MYSQL?

Yes it is possible without using MySQLi extension.

Simply use CLIENT_MULTI_STATEMENTS in mysql_connect's 5th argument.

Refer to the comments below Husni's post for more information.

How to convert entire dataframe to numeric while preserving decimals?

Using dplyr (a bit like sapply..)

df2 <- mutate_all(df1, function(x) as.numeric(as.character(x)))

which gives:

glimpse(df2)
Observations: 4
Variables: 2
$ a <dbl> 0.01, 0.02, 0.03, 0.04
$ b <dbl> 2, 4, 5, 7

from your df1 which was:

glimpse(df1)
Observations: 4
Variables: 2
$ a <fctr> 0.01, 0.02, 0.03, 0.04
$ b <dbl> 2, 4, 5, 7

How to form tuple column from two columns in Pandas

In [10]: df
Out[10]:
          A         B       lat      long
0  1.428987  0.614405  0.484370 -0.628298
1 -0.485747  0.275096  0.497116  1.047605
2  0.822527  0.340689  2.120676 -2.436831
3  0.384719 -0.042070  1.426703 -0.634355
4 -0.937442  2.520756 -1.662615 -1.377490
5 -0.154816  0.617671 -0.090484 -0.191906
6 -0.705177 -1.086138 -0.629708  1.332853
7  0.637496 -0.643773 -0.492668 -0.777344
8  1.109497 -0.610165  0.260325  2.533383
9 -1.224584  0.117668  1.304369 -0.152561

In [11]: df['lat_long'] = df[['lat', 'long']].apply(tuple, axis=1)

In [12]: df
Out[12]:
          A         B       lat      long                             lat_long
0  1.428987  0.614405  0.484370 -0.628298      (0.484370195967, -0.6282975278)
1 -0.485747  0.275096  0.497116  1.047605      (0.497115615839, 1.04760475074)
2  0.822527  0.340689  2.120676 -2.436831      (2.12067574274, -2.43683074367)
3  0.384719 -0.042070  1.426703 -0.634355      (1.42670326172, -0.63435462504)
4 -0.937442  2.520756 -1.662615 -1.377490     (-1.66261469102, -1.37749004179)
5 -0.154816  0.617671 -0.090484 -0.191906  (-0.0904840623396, -0.191905582481)
6 -0.705177 -1.086138 -0.629708  1.332853     (-0.629707821728, 1.33285348929)
7  0.637496 -0.643773 -0.492668 -0.777344   (-0.492667604075, -0.777344111021)
8  1.109497 -0.610165  0.260325  2.533383        (0.26032456699, 2.5333825651)
9 -1.224584  0.117668  1.304369 -0.152561     (1.30436900612, -0.152560909725)

How to set a default value with Html.TextBoxFor?

Try this also, that is remove new { } and replace it with string.

<%: Html.TextBoxFor(x => x.Age,"0") %>

Why is my element value not getting changed? Am I using the wrong function?

How to address your textbox depends on the HTML-code:

<!-- 1 --><input type="textbox" id="Tue" />
<!-- 2 --><input type="textbox" name="Tue" />

If you use the 'id' attribute:

var textbox = document.getElementById('Tue');

for 'name':

var textbox = document.getElementsByName('Tue')[0]

(Note that getElementsByName() returns all elements with the name as array, therefore we use [0] to access the first one)

Then, use the 'value' attribute:

textbox.value = 'Foobar';

The instance of entity type cannot be tracked because another instance of this type with the same key is already being tracked

public async Task<Product> GetValue(int id)
    {
        Product Products = await _context.Products.AsNoTracking().FirstOrDefaultAsync(x => x.Id == id);
        return Products;
    }

AsNoTracking()

Insert variable into Header Location PHP

header('Location: http://linkhere.com/' . $your_variable);

C#: Waiting for all threads to complete

This may not be an option for you, but if you can use the Parallel Extension for .NET then you could use Tasks instead of raw threads and then use Task.WaitAll() to wait for them to complete.

How to install Intellij IDEA on Ubuntu?

try simple way to install intellij idea

Install IntelliJ on Ubuntu using Ubuntu Make

You need to install Ubuntu Make first. If you are using Ubuntu 16.04, 18.04 or a higher version, you can install Ubuntu Make using the command below:

  1. sudo apt install ubuntu-make

Once you have Ubuntu Make installed, you can use the command below to install IntelliJ IDEA Community edition:

  1. umake ide idea

To install the IntelliJ IDEA Ultimate edition, use the command below:

  1. umake ide idea-ultimate

To remove IntelliJ IDEA installed via Ubuntu Make, use the command below for your respective versions:

  1. umake -r ide idea
  2. umake -r ide idea-ultimate

you may visit for more option.

https://itsfoss.com/install-intellij-ubuntu-linux/

How can I shutdown Spring task executor/scheduler pools before all other beans in the web app are destroyed?

I had similar issues with the threads being started in Spring bean. These threads were not closing properly after i called executor.shutdownNow() in @PreDestroy method. So the solution for me was to let the thread finsih with IO already started and start no more IO, once @PreDestroy was called. And here is the @PreDestroy method. For my application the wait for 1 second was acceptable.

@PreDestroy
    public void beandestroy() {
        this.stopThread = true;
        if(executorService != null){
            try {
                // wait 1 second for closing all threads
                executorService.awaitTermination(1, TimeUnit.SECONDS);
            } catch (InterruptedException e) {
                Thread.currentThread().interrupt();
            }
        }
    }

Here I have explained all the issues faced while trying to close threads.http://programtalk.com/java/executorservice-not-shutting-down/

How do I select the "last child" with a specific class name in CSS?

You can use the adjacent sibling selector to achieve something similar, that might help.

.list-item.other-class + .list-item:not(.other-class)

Will effectively target the immediately following element after the last element with the class other-class.

Read more here: https://css-tricks.com/almanac/selectors/a/adjacent-sibling/

Symbolicating iPhone App Crash Reports

I found out most of proposed alternatives did not work in latest XCode (tested with Xcode 10). For example, I had no luck drag-dropping .crash logs in Xcode -> Organizer -> Device logs -view.

I recommend using Symbolicator tool https://github.com/agentsim/Symbolicator

  • Git clone Symbolicator repository and compile and run with Xcode
  • Copy .crash file (ascii file, with stack trace in begging of file) and .xarchive of crashing release to same temporarly folder
  • Drag and drop .crash file to Symbolicator icon in Dock
  • In 5-30 secs symbolicated crash file is produced in same folder as .crash and .xarchive are

Stop executing further code in Java

Just do:

public void onClick() {
    if(condition == true) {
        return;
    }
    string.setText("This string should not change if condition = true");
}

It's redundant to write if(condition == true), just write if(condition) (This way, for example, you'll not write = by mistake).

Using variables in Nginx location rules

A modified python version of @danack's PHP generate script. It generates all files & folders that live inside of build/ to the parent directory, replacing all {{placeholder}} matches. You need to cd into build/ before running the script.

File structure

build/
-- (files/folders you want to generate)
-- build.py

sites-available/...
sites-enabled/...
nginx.conf
...

build.py

import os, re

# Configurations
target = os.path.join('.', '..')
variables = {
  'placeholder': 'your replacement here'
}


# Loop files
def loop(cb, subdir=''):
  dir = os.path.join('.', subdir);

  for name in os.listdir(dir):
    file = os.path.join(dir, name)
    newsubdir = os.path.join(subdir, name)

    if name == 'build.py': continue
    if os.path.isdir(file): loop(cb, newsubdir)
    else: cb(subdir, name)


# Update file
def replacer(subdir, name):
  dir  = os.path.join(target, subdir)
  file = os.path.join(dir, name)
  oldfile = os.path.join('.', subdir, name)

  with open(oldfile, "r") as fin:
    data = fin.read()

  for key, replacement in variables.iteritems():
    data = re.sub(r"{{\s*" + key + "\s*}}", replacement, data)

  if not os.path.exists(dir):
    os.makedirs(dir)

  with open(file, "w") as fout:
    fout.write(data)


# Start variable replacements.
loop(replacer)

angularjs - ng-repeat: access key and value from JSON array object

Solution I have json object which has data

[{"name":"Ata","email":"[email protected]"}]

You can use following approach to iterate through ng-repeat and use table format instead of list.

<div class="container" ng-controller="fetchdataCtrl">    
  <ul ng-repeat="item in numbers">
    <li>            
      {{item.name}}: {{item.email}}
    </li>
  </ul>     
</div>

How to deal with missing src/test/java source folder in Android/Maven project?

Select project -> New -> Folder (not source folder) -> Select the project again -> Enter the folder name as (src/test/java) -> finish. That's it.

If the test source is missing, it would link it automatically. If not, then require to link it manually.

How do I find Waldo with Mathematica?

I've found Waldo!

waldo had been found

How I've done it

First, I'm filtering out all colours that aren't red

waldo = Import["http://www.findwaldo.com/fankit/graphics/IntlManOfLiterature/Scenes/DepartmentStore.jpg"];
red = Fold[ImageSubtract, #[[1]], Rest[#]] &@ColorSeparate[waldo];

Next, I'm calculating the correlation of this image with a simple black and white pattern to find the red and white transitions in the shirt.

corr = ImageCorrelate[red, 
   Image@Join[ConstantArray[1, {2, 4}], ConstantArray[0, {2, 4}]], 
   NormalizedSquaredEuclideanDistance];

I use Binarize to pick out the pixels in the image with a sufficiently high correlation and draw white circle around them to emphasize them using Dilation

pos = Dilation[ColorNegate[Binarize[corr, .12]], DiskMatrix[30]];

I had to play around a little with the level. If the level is too high, too many false positives are picked out.

Finally I'm combining this result with the original image to get the result above

found = ImageMultiply[waldo, ImageAdd[ColorConvert[pos, "GrayLevel"], .5]]

Column count doesn't match value count at row 1

  1. you missed the comma between two values or column name
  2. you put extra values or an extra column name

Remove Project from Android Studio

Found this elsewhere on the web, it deletes basically everything (except the workspace.xml file, which you can delete manually from the project folder).

  1. Right Click on the project name under the save icon.
  2. Click delete
  3. Go to your project folder and check all the files were deleted.

enter image description here

Is it possible to run an .exe or .bat file on 'onclick' in HTML

It is possible when the page itself is opened via a file:/// path.

<button onclick="window.open('file:///C:/Windows/notepad.exe')">
    Launch notepad
</button>

However, the moment you put it on a webserver (even if you access it via http://localhost/), you will get an error:

Error: Access to 'file:///C:/Windows/notepad.exe' from script denied

A warning - comparison between signed and unsigned integer expressions

or use this header library and write:

// |notEqaul|less|lessEqual|greater|greaterEqual
if(sweet::equal(valueA,valueB))

and don't care about signed/unsigned or different sizes

Origin http://localhost is not allowed by Access-Control-Allow-Origin

If you want everyone to be able to access the Node app, then try using

res.header('Access-Control-Allow-Origin', "*")

That will allow requests from any origin. The CORS enable site has a lot of information on the different Access-Control-Allow headers and how to use them.

I you are using Chrome, please look at this bug bug regarding localhost and Access-Control-Allow-Origin. There is another StackOverflow question here that details the issue.

Remove all special characters except space from a string using JavaScript

_x000D_
_x000D_
const input = `#if_1 $(PR_CONTRACT_END_DATE) == '23-09-2019' # _x000D_
Test27919<[email protected]> #elseif_1 $(PR_CONTRACT_START_DATE) ==  '20-09-2019' #_x000D_
Sender539<[email protected]> #elseif_1 $(PR_ACCOUNT_ID) == '1234' #_x000D_
AdestraSID<[email protected]> #else_1#Test27919<[email protected]>#endif_1#`;_x000D_
const replaceString = input.split('$(').join('->').split(')').join('<-');_x000D_
_x000D_
_x000D_
console.log(replaceString.match(/(?<=->).*?(?=<-)/g));
_x000D_
_x000D_
_x000D_

good postgresql client for windows?

EMS's SQL Manager is much easier to use and has many more features than either phpPgAdmin or PG Admin III. However, it's windows only and you have to pay for it.

Validation of file extension before uploading file

we can check it on submit or we can make change event of that control

var fileInput = document.getElementById('file');
    var filePath = fileInput.value;
    var allowedExtensions = /(\.jpeg|\.JPEG|\.gif|\.GIF|\.png|\.PNG)$/;
    if (filePath != "" && !allowedExtensions.exec(filePath)) {
    alert('Invalid file extention pleasse select another file');
    fileInput.value = '';
    return false;
    }

python pandas dataframe to dictionary

Simplest solution:

df.set_index('id').T.to_dict('records')

Example:

df= pd.DataFrame([['a',1],['a',2],['b',3]], columns=['id','value'])
df.set_index('id').T.to_dict('records')

If you have multiple values, like val1, val2, val3,etc and u want them as lists, then use the below code:

df.set_index('id').T.to_dict('list')

CSS Display an Image Resized and Cropped

Thanks sanchothefat.

I have an improvement to your answer. As crop is very tailored for every image, this definitions should be at the HTML instead of CSS.

<div style="overflow:hidden;">
   <img src="img.jpg" alt="" style="margin:-30% 0px -10% 0px;" />
</div>

How can I concatenate a string and a number in Python?

Since Python is a strongly typed language, concatenating a string and an integer as you may do in Perl makes no sense, because there's no defined way to "add" strings and numbers to each other.

Explicit is better than implicit.

...says "The Zen of Python", so you have to concatenate two string objects. You can do this by creating a string from the integer using the built-in str() function:

>>> "abc" + str(9)
'abc9'

Alternatively use Python's string formatting operations:

>>> 'abc%d' % 9
'abc9'

Perhaps better still, use str.format():

>>> 'abc{0}'.format(9)
'abc9'

The Zen also says:

There should be one-- and preferably only one --obvious way to do it.

Which is why I've given three options. It goes on to say...

Although that way may not be obvious at first unless you're Dutch.

How to extract text from the PDF document?

I know that this topic is quite old, but this need is still alive. I read many documents, forum and script and build a new advanced one which supports compressed and uncompressed pdf :

https://gist.github.com/smalot/6183152

Hope it helps everone

Running EXE with parameters

System.Diagnostics.Process.Start("PATH to exe", "Command Line Arguments");

Async await in linq select

Existing code is working, but is blocking the thread.

.Select(async ev => await ProcessEventAsync(ev))

creates a new Task for every event, but

.Select(t => t.Result)

blocks the thread waiting for each new task to end.

In the other hand your code produce the same result but keeps asynchronous.

Just one comment on your first code. This line

var tasks = await Task.WhenAll(events...

will produce a single Task<TResult[]> so the variable should be named in singular.

Finally your last code make the same but is more succinct.

For reference: Task.Wait / Task.WhenAll

Getting around the Max String size in a vba function?

I may have missed something here, but why can't you just declare your string with the desired size? For example, in my VBA code I often use something like:

Dim AString As String * 1024

which provides for a 1k string. Obviously, you can use whatever declaration you like within the larger limits of Excel and available memory etc.

This may be a little inefficient in some cases, and you will probably wish to use Trim(AString) like constructs to obviate any superfluous trailing blanks. Still, it easily exceeds 256 chars.

Retrieve column names from java.sql.ResultSet

When you need the column names, but do not want to grab entries:

PreparedStatement stmt = connection.prepareStatement("SHOW COLUMNS FROM `yourTable`");

ResultSet set = stmt.executeQuery();

//store all of the columns names
List<String> names = new ArrayList<>();
while (set.next()) { names.add(set.getString("Field")); }

NOTE: Only works with MySQL

Why aren't Xcode breakpoints functioning?

On Xcode 6.4, I needed to reboot my Mac.

(Tried enabling/disabling breakpoints, rebooting iOS device, restarting Xcode, deleting breakpoint files from the workspace package...)

How do I select between the 1st day of the current month and current day in MySQL?

try this :

SET @StartDate = DATE_SUB(DATE(NOW()),INTERVAL (DAY(NOW())-1) DAY);
SET @EndDate = ADDDATE(CURDATE(),1);
select * from table where (date >= @StartDate and date < @EndDate);

How do I fix the error 'Named Pipes Provider, error 40 - Could not open a connection to' SQL Server'?

Thanks to Damian...

TCP/IP Named Pipes ... both enabled

Web Config....(for localhost)

<add name="FooData" connectionString="Data Source=localhost\InstanceName;Initial Catalog=DatabaseName;Integrated Security=True;" providerName="System.Data.SqlClient" />

How do I make a C++ console program exit?

else if(Decision >= 3)
    {
exit(0);
    }

Android Studio Could not initialize class org.codehaus.groovy.runtime.InvokerHelper

For me the solution was to upgrade the gradle version to 6.3 from the android project structure (java 14.0.1 is already installed on my pc).

Could not resolve this reference. Could not locate the assembly

I had this issue after VS mac updation. iOS sdk was updated. I was referring the ios dll in project folder. The version number in the hintpath was changed.

Earlier:

<Reference Include="Xamarin.iOS">   
     <HintPath>..\..\..\..\..\..\..\..\Library\Frameworks\Xamarin.iOS.framework\Versions\13.18.2.1\lib\mono\Xamarin.iOS\Xamarin.iOS.dll</HintPath>
    </Reference>
    <Reference Include="Xamarin.iOS">
      <HintPath>..\..\..\..\..\..\..\Library\Frameworks\Xamarin.iOS.framework\Versions\13.18.1.31\lib\mono\Xamarin.iOS\Xamarin.iOS.dll</HintPath>
    </Reference>
    <Reference Include="Xamarin.iOS">          <HintPath>..\..\..\..\..\..\..\Library\Frameworks\Xamarin.iOS.framework\Versions\13.18.3.2\lib\mono\Xamarin.iOS\Xamarin.iOS.dll</HintPath>
    </Reference>

I referred to the numbers in the previous commit and changed only the numbers in project folder, did nothing in android,ios folders. Worked for me!!!

Now:

<Reference Include="Xamarin.iOS">                                                            
 <HintPath>..\..\..\..\..\..\..\..\Library\Frameworks\Xamarin.iOS.framework\Versions\13.20.2.2\lib\mono\Xamarin.iOS\Xamarin.iOS.dll</HintPath>
        </Reference> 

NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equalsIgnoreCase(java.lang.String)' on a null object reference

called_from must be null. Add a test against that condition like

if (called_from != null && called_from.equalsIgnoreCase("add")) {

or you could use Yoda conditions (per the Advantages in the linked Wikipedia article it can also solve some types of unsafe null behavior they can be described as placing the constant portion of the expression on the left side of the conditional statement)

if ("add".equalsIgnoreCase(called_from)) { // <-- safe if called_from is null

Jersey stopped working with InjectionManagerFactory not found

As far as I can see dependencies have changed between 2.26-b03 and 2.26-b04 (HK2 was moved to from compile to testCompile)... there might be some change in the jersey dependencies that has not been completed yet (or which lead to a bug).

However, right now the simple solution is to stick to an older version :-)

Setting up FTP on Amazon Cloud Server

To enable passive ftp on an EC2 server, you need to configure the ports that your ftp server should use for inbound connections, then open a list of available ports for the ftp client data connections.

I'm not that familiar with linux, but the commands you posted are the steps to install the ftp server, configure the ec2 firewall rules (through the AWS API), then configure the ftp server to use the ports you allowed on the ec2 firewall.

So this step installs the ftp client (VSFTP)

> yum install vsftpd

These steps configure the ftp client

> vi /etc/vsftpd/vsftpd.conf
--    Add following lines at the end of file --
     pasv_enable=YES
     pasv_min_port=1024
     pasv_max_port=1048
     pasv_address=<Public IP of your instance> 
> /etc/init.d/vsftpd restart

but the other two steps are easier done through the amazon console under EC2 Security groups. There you need to configure the security group that is assigned to your server to allow connections on ports 20,21, and 1024-1048

Error: Java: invalid target release: 11 - IntelliJ IDEA

If building a project through a build system (Maven, Gradle etc..) works but IntelliJ show Invalid target release error, then do the following,

  1. Close IntelliJ

  2. Go to the directory of the project

  3. Delete the .idea/ directory

  4. Start IntelliJ with the project's directory

This will re-create the .idea/ directory and will no longer show the error.

NOTE: Any repository specific IntelliJ settings that you have added would be deleted when the .idea/ directory is deleted and they will be re-created with the defaults.

What's the difference between display:inline-flex and display:flex?

You need a bit more information so that the browser knows what you want. For instance, the children of the container need to be told "how" to flex.

Updated Fiddle

I've added #wrapper > * { flex: 1; margin: auto; } to your CSS and changed inline-flex to flex, and you can see how the elements now space themselves out evenly on the page.

How to hide TabPage from TabControl

+1 for microsoft :-) .
I managed to do it this way:
(it assumes you have a Next button that displays the next TabPage - tabSteps is the name of the Tab control)
At start up, save all the tabpages in a proper list.
When user presses Next button, remove all the TabPages in the tab control, then add that with the proper index:

int step = -1;
List<TabPage> savedTabPages;

private void FMain_Load(object sender, EventArgs e) {
    // save all tabpages in the list
    savedTabPages = new List<TabPage>();
    foreach (TabPage tp in tabSteps.TabPages) {
        savedTabPages.Add(tp);
    }
    SelectNextStep();
}

private void SelectNextStep() {
    step++;
    // remove all tabs
    for (int i = tabSteps.TabPages.Count - 1; i >= 0 ; i--) {
            tabSteps.TabPages.Remove(tabSteps.TabPages[i]);
    }

    // add required tab
    tabSteps.TabPages.Add(savedTabPages[step]);
}

private void btnNext_Click(object sender, EventArgs e) {
    SelectNextStep();
}

Update

public class TabControlHelper {
    private TabControl tc;
    private List<TabPage> pages;
    public TabControlHelper(TabControl tabControl) {
        tc = tabControl;
        pages = new List<TabPage>();
        foreach (TabPage p in tc.TabPages) {
            pages.Add(p);
        }
    }

    public void HideAllPages() {
        foreach(TabPage p in pages) {
            tc.TabPages.Remove(p);
        }
    }

    public void ShowAllPages() {
        foreach (TabPage p in pages) {
            tc.TabPages.Add(p);
        }
    }

    public void HidePage(TabPage tp) {
        tc.TabPages.Remove(tp);
    }        

    public void ShowPage(TabPage tp) {
        tc.TabPages.Add(tp);
    }
}  

Installing MySQL Python on Mac OS X

the below may be help.

brew install mysql-connector-c
CFLAGS =-I/usr/local/Cellar/mysql-connector-c/6.1.11/include pip install MySQL-python
brew unlink mysql-connector-c

Removing a non empty directory programmatically in C or C++

You can use opendir and readdir to read directory entries and unlink to delete them.