Programs & Examples On #Acts as taggable on

ActsAsTaggableOn is a Ruby on Rails gem for handling generic tagging.

Get pixel color from canvas, on mousemove

I know this is an old question, but here's an alternative. I'd store that image data in an array, then, on mouse move event over the canvas:

var index = (Math.floor(y) * canvasWidth + Math.floor(x)) * 4
var r = data[index]
var g = data[index + 1]
var b = data[index + 2]
var a = data[index + 3]

A lot easier than getting the imageData everytime.

Retrieving an element from array list in Android?

U cant try this

for (WordList i : words) {
     words.get(words.indexOf(i));
 }

Angular JS break ForEach

var ary = ["JavaScript", "Java", "CoffeeScript", "TypeScript"];
var keepGoing = true;
ary.forEach(function(value, index, _ary) {
    console.log(index)
    keepGoing = true;
    ary.forEach(function(value, index, _ary) {
        if(keepGoing){ 
            if(index==2){
                keepGoing=false;
            }
            else{
                console.log(value)
            }

        }      
    });
});

MySQL high CPU usage

If this server is visible to the outside world, It's worth checking if it's having lots of requests to connect from the outside world (i.e. people trying to break into it)

Initialise numpy array of unknown length

a = np.empty(0)
for x in y:
    a = np.append(a, x)

Insert a new row into DataTable

@William You can use NewRow method of the datatable to get a blank datarow and with the schema as that of the datatable. You can populate this datarow and then add the row to the datatable using .Rows.Add(DataRow) OR .Rows.InsertAt(DataRow, Position). The following is a stub code which you can modify as per your convenience.

//Creating dummy datatable for testing
DataTable dt = new DataTable();
DataColumn dc = new DataColumn("col1", typeof(String));
dt.Columns.Add(dc);

dc = new DataColumn("col2", typeof(String));
dt.Columns.Add(dc);

dc = new DataColumn("col3", typeof(String));
dt.Columns.Add(dc);

dc = new DataColumn("col4", typeof(String));
dt.Columns.Add(dc);

DataRow dr = dt.NewRow();

dr[0] = "coldata1";
dr[1] = "coldata2";
dr[2] = "coldata3";
dr[3] = "coldata4";

dt.Rows.Add(dr);//this will add the row at the end of the datatable
//OR
int yourPosition = 0;
dt.Rows.InsertAt(dr, yourPosition);

C# An established connection was aborted by the software in your host machine

This problem appear if two software use same port for connecting to the server
try to close the port by cmd according to your operating system
then reboot your Android studio or your Eclipse or your Software.

Multiple conditions in if statement shell script

if using /bin/sh you can use:

if [ <condition> ] && [ <condition> ]; then
    ...
fi

if using /bin/bash you can use:

if [[ <condition> && <condition> ]]; then
    ...
fi

Pandas left outer join multiple dataframes on multiple columns

One can also do this with a compact version of @TomAugspurger's answer, like so:

df = df1.merge(df2, how='left', on=['Year', 'Week', 'Colour']).merge(df3[['Week', 'Colour', 'Val3']], how='left', on=['Week', 'Colour'])

What is the easiest/best/most correct way to iterate through the characters of a string in Java?

Two options

for(int i = 0, n = s.length() ; i < n ; i++) { 
    char c = s.charAt(i); 
}

or

for(char c : s.toCharArray()) {
    // process c
}

The first is probably faster, then 2nd is probably more readable.

Android Fragment onAttach() deprecated

The answer below is related to this deprecation warning occurring in the Fragments tutorial on the Android developer website and may not be related to the posts above.

I used this code on the tutorial lesson and it did worked.

public void onAttach(Context context){
    super.onAttach(context);

    Activity activity = getActivity();

I was worried that activity maybe null as what the documentation states.

getActivity

FragmentActivity getActivity () Return the FragmentActivity this fragment is currently associated with. May return null if the fragment is associated with a Context instead.

But the onCreate on the main_activity clearly shows that the fragment was loaded and so after this method, calling get activity from the fragment will return the main_activity class.

getSupportFragmentManager().beginTransaction() .add(R.id.fragment_container, firstFragment).commit();

I hope I am correct with this. I am an absolute newbie.

how to change php version in htaccess in server

Note that all above answers are correct for Apache+ setups. They're less likely to work with more current PHP-FPM setups. Those can typically only be defined in VirtualHost section, not .htaccess.

Again, this highly depends on how your hoster has configured PHP. Each domain/user will typically have it's own running PHP FPM instance. And subsequently a generic …/x-httpd-php52 type will not be recognized.

See ServerFault: Alias a FastCGI proxy protocol handler via Action/ScriptAlias/etc for some overview.

For Apache 2.4.10+/ configs you might be able to use something like:

 AddHandler "proxy:unix:/var/run/php-fpm-usr123.sock|fcgi://localhost" .php

Or SetHandler with name mapping from your .htaccess. But again, consulting your hoster on the concrete FPM socket is unavoidable. There's no generic answer to this on modern PHP-FPM setups.

Rewrite all requests to index.php with nginx

Flat and simple config without rewrite, can work in some cases:

location / {
    fastcgi_pass unix:/var/run/php5-fpm.sock;
    include fastcgi_params;
    fastcgi_param SCRIPT_FILENAME /home/webuser/site/index.php;
}

cannot connect to pc-name\SQLEXPRESS

try using IP instead of pc name. If the ip working, then it might be the name pipe is not enable. If it;s still not working then the login using windows might be disabled.

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

In gradle-wrapper.properties file, updating the Gradle to 6.3 solved the problem on Mac OS Catalina

distributionUrl=https://services.gradle.org/distributions/gradle-6.3-bin.zip

Query to display all tablespaces in a database and datafiles

SELECT a.file_name,
       substr(A.tablespace_name,1,14) tablespace_name,
       trunc(decode(A.autoextensible,'YES',A.MAXSIZE-A.bytes+b.free,'NO',b.free)/1024/1024) free_mb,
       trunc(a.bytes/1024/1024) allocated_mb,
       trunc(A.MAXSIZE/1024/1024) capacity,
       a.autoextensible ae
FROM (
     SELECT file_id, file_name,
            tablespace_name,
            autoextensible,
            bytes,
            decode(autoextensible,'YES',maxbytes,bytes) maxsize
     FROM   dba_data_files
     GROUP BY file_id, file_name,
              tablespace_name,
              autoextensible,
              bytes,
              decode(autoextensible,'YES',maxbytes,bytes)
     ) a,
     (SELECT file_id,
             tablespace_name,
             sum(bytes) free
      FROM   dba_free_space
      GROUP BY file_id,
               tablespace_name
      ) b
WHERE a.file_id=b.file_id(+)
AND A.tablespace_name=b.tablespace_name(+)
ORDER BY A.tablespace_name ASC; 

jQuery: Test if checkbox is NOT checked

if ( $("#checkSurfaceEnvironment-1").is(":checked") && $("#checkSurfaceEnvironment-2").not(":checked") )

Jdbctemplate query for string: EmptyResultDataAccessException: Incorrect result size: expected 1, actual 0

You may also use a ResultSetExtractor instead of a RowMapper. Both are just as easy as one another, the only difference is you call ResultSet.next().

public String test() {
    String sql = "select ID_NMB_SRZ from codb_owner.TR_LTM_SLS_RTN "
                 + " where id_str_rt = '999' and ID_NMB_SRZ = '60230009999999'";
    return jdbc.query(sql, new ResultSetExtractor<String>() {
        @Override
        public String extractData(ResultSet rs) throws SQLException,
                                                       DataAccessException {
            return rs.next() ? rs.getString("ID_NMB_SRZ") : null;
        }
    });
}

The ResultSetExtractor has the added benefit that you can handle all cases where there are more than one row or no rows returned.

UPDATE: Several years on and I have a few tricks to share. JdbcTemplate works superbly with java 8 lambdas which the following examples are designed for but you can quite easily use a static class to achieve the same.

While the question is about simple types, these examples serve as a guide for the common case of extracting domain objects.

First off. Let's suppose that you have an account object with two properties for simplicity Account(Long id, String name). You would likely wish to have a RowMapper for this domain object.

private static final RowMapper<Account> MAPPER_ACCOUNT =
        (rs, i) -> new Account(rs.getLong("ID"),
                               rs.getString("NAME"));

You may now use this mapper directly within a method to map Account domain objects from a query (jt is a JdbcTemplate instance).

public List<Account> getAccounts() {
    return jt.query(SELECT_ACCOUNT, MAPPER_ACCOUNT);
}

Great, but now we want our original problem and we use my original solution reusing the RowMapper to perform the mapping for us.

public Account getAccount(long id) {
    return jt.query(
            SELECT_ACCOUNT,
            rs -> rs.next() ? MAPPER_ACCOUNT.mapRow(rs, 1) : null,
            id);
}

Great, but this is a pattern you may and will wish to repeat. So you can create a generic factory method to create a new ResultSetExtractor for the task.

public static <T> ResultSetExtractor singletonExtractor(
        RowMapper<? extends T> mapper) {
    return rs -> rs.next() ? mapper.mapRow(rs, 1) : null;
}

Creating a ResultSetExtractor now becomes trivial.

private static final ResultSetExtractor<Account> EXTRACTOR_ACCOUNT =
        singletonExtractor(MAPPER_ACCOUNT);

public Account getAccount(long id) {
    return jt.query(SELECT_ACCOUNT, EXTRACTOR_ACCOUNT, id);
}

I hope this helps to show that you can now quite easily combine parts in a powerful way to make your domain simpler.

UPDATE 2: Combine with an Optional for optional values instead of null.

public static <T> ResultSetExtractor<Optional<T>> singletonOptionalExtractor(
        RowMapper<? extends T> mapper) {
    return rs -> rs.next() ? Optional.of(mapper.mapRow(rs, 1)) : Optional.empty();
}

Which now when used could have the following:

private static final ResultSetExtractor<Optional<Double>> EXTRACTOR_DISCOUNT =
        singletonOptionalExtractor(MAPPER_DISCOUNT);

public double getDiscount(long accountId) {
    return jt.query(SELECT_DISCOUNT, EXTRACTOR_DISCOUNT, accountId)
            .orElse(0.0);
}

AngularJS Multiple ng-app within a page

<html>
<head>
    <script src="angular.min.js"></script>
</head>
<body>
<div ng-app="shoppingCartParentModule" >
     <div ng-controller="ShoppingCartController">
        <h1>Your order</h1>
        <div ng-repeat="item in items">
            <span>{{item.product_name}}</span>
            <span>{{item.price | currency}}</span>
            <button ng-click="remove($index);">Remove</button>
        </div>
    </div>

    <div ng-controller="NamesController">
        <h1>List of Names</h1>
        <div ng-repeat="name in names">
            <p>{{name.username}}</p>
        </div>
    </div>
</div>
</body>
<script>
var shoppingCartModule = angular.module("shoppingCart", [])
            shoppingCartModule.controller("ShoppingCartController",
                function($scope) {
                    $scope.items = [
                        {product_name: "Product 1", price: 50},
                        {product_name: "Product 2", price: 20},
                        {product_name: "Product 3", price: 180}
                    ];
                    $scope.remove = function(index) {
                        $scope.items.splice(index, 1);
                    }
                }
            );
            var namesModule = angular.module("namesList", [])
            namesModule.controller("NamesController",
                function($scope) {
                    $scope.names = [
                        {username: "Nitin"},
                        {username: "Mukesh"}
                    ];
                }
            );
   angular.module("shoppingCartParentModule",["shoppingCart","namesList"])
</script>
</html>

Python mysqldb: Library not loaded: libmysqlclient.18.dylib

For those using homebrew you might fix this with:

$ brew link mysql

Multiple submit buttons in an HTML form

If you have multiple active buttons on one page then you can do something like this:

Mark the first button you want to trigger on the Enter keypress as the default button on the form. For the second button, associate it to the Backspace button on the keyboard. The Backspace eventcode is 8.

_x000D_
_x000D_
$(document).on("keydown", function(event) {_x000D_
  if (event.which.toString() == "8") {_x000D_
    var findActiveElementsClosestForm = $(document.activeElement).closest("form");_x000D_
_x000D_
    if (findActiveElementsClosestForm && findActiveElementsClosestForm.length) {_x000D_
      $("form#" + findActiveElementsClosestForm[0].id + " .secondary_button").trigger("click");_x000D_
    }_x000D_
  }_x000D_
});
_x000D_
<script src="https://ajax.aspnetcdn.com/ajax/jQuery/jquery-3.2.1.min.js"></script>_x000D_
_x000D_
<form action="action" method="get" defaultbutton="TriggerOnEnter">_x000D_
  <input type="submit" id="PreviousButton" name="prev" value="Prev" class="secondary_button" />_x000D_
  <input type="submit" id='TriggerOnEnter' name="next" value="Next" class="primary_button" />_x000D_
</form>
_x000D_
_x000D_
_x000D_

What is the difference between call and apply?

The difference is that call() takes the function arguments separately, and apply() takes the function arguments in an array.

#define macro for debug printing in C?

According to http://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html, there should be a ## before __VA_ARGS__.

Otherwise, a macro #define dbg_print(format, ...) printf(format, __VA_ARGS__) will not compile the following example: dbg_print("hello world");.

List only stopped Docker containers

Only stopped containers can be listed using:

docker ps --filter "status=exited"

or

docker ps -f "status=exited"

Attaching click event to a JQuery object not yet added to the DOM

Does using .live work for you?

$("#my-button").live("click", function(){ alert("yay!"); }); 

http://api.jquery.com/live/

EDIT

As of jQuery 1.7, the .live() method is deprecated. Use .on() to attach event handlers. Users of older versions of jQuery should use .delegate() in preference to .live().

http://api.jquery.com/on/

JQuery window scrolling event?

See jQuery.scroll(). You can bind this to the window element to get your desired event hook.

On scroll, then simply check your scroll position:

$(window).scroll(function() {
  var scrollTop = $(window).scrollTop();
  if ( scrollTop > $(headerElem).offset().top ) { 
    // display add
  }
});

Reloading a ViewController

Update the data ... change button titles..whatever stuff you have to update..

then just call

[self.view setNeedsDisplay];

C: How to free nodes in the linked list?

One function can do the job,

void free_list(node *pHead)
{
    node *pNode = pHead, *pNext;

    while (NULL != pNode)
    {
        pNext = pNode->next;
        free(pNode);
        pNode = pNext;
    }

}

Entity Framework The underlying provider failed on Open

  1. Search "Component Services" in Programs and Files
  2. Go to Services
  3. Find "Distributed Transaction Coordinator" Service
  4. Right click and Restart the Service

You've just done a restart of the service and the code should run without errors

PostgreSQL Autoincrement

Create Sequence.

CREATE SEQUENCE user_role_id_seq
  INCREMENT 1
  MINVALUE 1
  MAXVALUE 9223372036854775807
  START 3
  CACHE 1;
ALTER TABLE user_role_id_seq
  OWNER TO postgres;

and alter table

ALTER TABLE user_roles ALTER COLUMN user_role_id SET DEFAULT nextval('user_role_id_seq'::regclass);

writing a batch file that opens a chrome URL

assuming chrome is his default browser: start http://url.site.you.com/path/to/joke should open that url in his browser.

The simplest way to comma-delimit a list?

Java 8 and later

Using StringJoiner class :

StringJoiner joiner = new StringJoiner(",");
for (Item item : list) {
    joiner.add(item.toString());
}
return joiner.toString();

Using Stream, and Collectors:

return list.stream().
       map(Object::toString).
       collect(Collectors.joining(",")).toString();

Java 7 and earlier

See also #285523

String delim = "";
for (Item i : list) {
    sb.append(delim).append(i);
    delim = ",";
}

What does `m_` variable prefix mean?

It is common practice in C++. This is because in C++ you can't have same name for the member function and member variable, and getter functions are often named without "get" prefix.

class Person
{
   public:
      std::string name() const;

   private:
      std::string name; // This would lead to a compilation error.
      std::string m_name; // OK.
};

main.cpp:9:19: error: duplicate member 'name'
      std::string name;
                  ^
main.cpp:6:19: note: previous declaration is here
      std::string name() const;
                  ^
1 error generated.

http://coliru.stacked-crooked.com/a/f38e7dbb047687ad

"m_" states for the "member". Prefix "_" is also common.

You shouldn't use it in programming languages that solve this problem by using different conventions/grammar.

npm not working after clearing cache

Try npm cache clean --force if it doesn't work then manually delete %appdata%\npm-cache folder.

It worked for me.

How to get the process ID to kill a nohup process?

About losing your putty: often the ps ... | awk/grep/perl/... process gets matched, too! So the old school trick is like this

ps -ef | grep -i [n]ohup 

That way the regex search doesn't match the regex search process!

Fast and simple String encrypt/decrypt in JAVA

If you are using Android then you can use android.util.Base64 class.

Encode:

passwd = Base64.encodeToString( passwd.getBytes(), Base64.DEFAULT );

Decode:

passwd = new String( Base64.decode( passwd, Base64.DEFAULT ) );

A simple and fast single line solution.

Set multiple system properties Java command line

You may be able to use the JAVA_TOOL_OPTIONS environment variable to set options. It worked for me with Rasbian. See Environment Variables and System Properties which has this to say:

In many environments, the command line is not readily accessible to start the application with the necessary command-line options.

This often happens with applications that use embedded VMs (meaning they use the Java Native Interface (JNI) Invocation API to start the VM), or where the startup is deeply nested in scripts. In these environments the JAVA_TOOL_OPTIONS environment variable can be useful to augment a command line.

When this environment variable is set, the JNI_CreateJavaVM function (in the JNI Invocation API), the JNI_CreateJavaVM function adds the value of the environment variable to the options supplied in its JavaVMInitArgs argument.

However this environment variable use may be disabled for security reasons.

In some cases, this option is disabled for security reasons. For example, on the Oracle Solaris operating system, this option is disabled when the effective user or group ID differs from the real ID.

See this example showing the difference between specifying on the command line versus using the JAVA_TOOL_OPTIONS environment variable.

screenshot showing use of JAVA_TOOL_OPTIONS environment variable

How to avoid Number Format Exception in java?

As always, the Jakarta Commons have at least part of the answer :

NumberUtils.isNumber()

This can be used to check most whether a given String is a number. You still have to choose what to do in case your String isnt a number ...

How To limit the number of characters in JTextField?

I have solved this problem by using the following code segment:

private void jTextField1KeyTyped(java.awt.event.KeyEvent evt) {
    boolean max = jTextField1.getText().length() > 4;
    if ( max ){
        evt.consume();
    }        
}

Variable's memory size in Python

Regarding the internal structure of a Python long, check sys.int_info (or sys.long_info for Python 2.7).

>>> import sys
>>> sys.int_info
sys.int_info(bits_per_digit=30, sizeof_digit=4)

Python either stores 30 bits into 4 bytes (most 64-bit systems) or 15 bits into 2 bytes (most 32-bit systems). Comparing the actual memory usage with calculated values, I get

>>> import math, sys
>>> a=0
>>> sys.getsizeof(a)
24
>>> a=2**100
>>> sys.getsizeof(a)
40
>>> a=2**1000
>>> sys.getsizeof(a)
160
>>> 24+4*math.ceil(100/30)
40
>>> 24+4*math.ceil(1000/30)
160

There are 24 bytes of overhead for 0 since no bits are stored. The memory requirements for larger values matches the calculated values.

If your numbers are so large that you are concerned about the 6.25% unused bits, you should probably look at the gmpy2 library. The internal representation uses all available bits and computations are significantly faster for large values (say, greater than 100 digits).

Eloquent ->first() if ->exists()

get returns Collection and is rather supposed to fetch multiple rows.

count is a generic way of checking the result:

$user = User::where(...)->first(); // returns Model or null
if (count($user)) // do what you want with $user

// or use this:
$user = User::where(...)->firstOrFail(); // returns Model or throws ModelNotFoundException

// count will works with a collection of course:
$users = User::where(...)->get(); // returns Collection always (might be empty)
if (count($users)) // do what you want with $users

DB2 Query to retrieve all table names for a given schema

SELECT
  name
FROM
  SYSIBM.SYSTABLES
WHERE
    type = 'T'
  AND
    creator = 'MySchema'
  AND
    name LIKE 'book_%';

Colors in JavaScript console

Emoji

You can use colors for text as others mentioned in their answers to have colorful text with a background or foreground color.

But you can use emojis instead! for example, you can use?? for warning messages and for error messages.

Or simply use these notebooks as a color:

_x000D_
_x000D_
console.log(': error message');
console.log(': warning message');
console.log(': ok status message');
console.log(': action message');
console.log(': canceled status message');
console.log(': Or anything you like and want to recognize immediately by color');
_x000D_
_x000D_
_x000D_

Bonus:

This method also helps you to quickly scan and find logs directly in the source code.

But Linux default emoji font is not colorful by default and you may want to make them colorful, first.

Set encoding and fileencoding to utf-8 in Vim

You can set the variable 'fileencodings' in your .vimrc.

This is a list of character encodings considered when starting to edit an existing file. When a file is read, Vim tries to use the first mentioned character encoding. If an error is detected, the next one in the list is tried. When an encoding is found that works, 'fileencoding' is set to it. If all fail, 'fileencoding' is set to an empty string, which means the value of 'encoding' is used.

See :help filencodings

If you often work with e.g. cp1252, you can add it there:

set fileencodings=ucs-bom,utf-8,cp1252,default,latin9

How can I shuffle an array?

Use the modern version of the Fisher–Yates shuffle algorithm:

/**
 * Shuffles array in place.
 * @param {Array} a items An array containing the items.
 */
function shuffle(a) {
    var j, x, i;
    for (i = a.length - 1; i > 0; i--) {
        j = Math.floor(Math.random() * (i + 1));
        x = a[i];
        a[i] = a[j];
        a[j] = x;
    }
    return a;
}

ES2015 (ES6) version

/**
 * Shuffles array in place. ES6 version
 * @param {Array} a items An array containing the items.
 */
function shuffle(a) {
    for (let i = a.length - 1; i > 0; i--) {
        const j = Math.floor(Math.random() * (i + 1));
        [a[i], a[j]] = [a[j], a[i]];
    }
    return a;
}

Note however, that swapping variables with destructuring assignment causes significant performance loss, as of October 2017.

Use

var myArray = ['1','2','3','4','5','6','7','8','9'];
shuffle(myArray);

Implementing prototype

Using Object.defineProperty (method taken from this SO answer) we can also implement this function as a prototype method for arrays, without having it show up in loops such as for (i in arr). The following will allow you to call arr.shuffle() to shuffle the array arr:

Object.defineProperty(Array.prototype, 'shuffle', {
    value: function() {
        for (let i = this.length - 1; i > 0; i--) {
            const j = Math.floor(Math.random() * (i + 1));
            [this[i], this[j]] = [this[j], this[i]];
        }
        return this;
    }
});

How do I disable right click on my web page?

Try This

<script language=JavaScript>
//Disable right mouse click Script

var message="Function Disabled!";

function clickIE4(){
if (event.button==2){
alert(message);
return false;
 }
}

function clickNS4(e){
if (document.layers||document.getElementById&&!document.all){
if (e.which==2||e.which==3){
alert(message);
return false;
}
}
}

if (document.layers){
document.captureEvents(Event.MOUSEDOWN);
document.onmousedown=clickNS4;
}
else if (document.all&&!document.getElementById){
document.onmousedown=clickIE4;
}

document.oncontextmenu=new Function("alert(message);return false")

</script>

Add A Year To Today's Date

This code adds the amount of years required for a date.

var d = new Date();
// => Tue Oct 01 2017 00:00:00 GMT-0700 (PDT)

var amountOfYearsRequired = 2;
d.setFullYear(d.getFullYear() + amountOfYearsRequired);
// => Tue Oct 01 2019 00:00:00 GMT-0700 (PDT)

Can a html button perform a POST request?

This can be done with an input element of a type "submit". This will appear as a button to the user and clicking the button will send the form.

<form action="" method="post">
    <input type="submit" name="upvote" value="Upvote" />
</form>

Update values from one column in same table to another in SQL Server

UPDATE `tbl_user` SET `name`=concat('tbl_user.first_name','tbl_user.last_name') WHERE student_roll>965

How do I compare two variables containing strings in JavaScript?

You can use javascript dedicate string compare method string1.localeCompare(string2). it will five you -1 if the string not equals, 0 for strings equal and 1 if string1 is sorted after string2.

<script>
    var to_check=$(this).val();
    var cur_string=$("#0").text();
    var to_chk = "that";
    var cur_str= "that";
    if(to_chk.localeCompare(cur_str) == 0){
        alert("both are equal");
        $("#0").attr("class","correct");    
    } else {
        alert("both are not equal");
        $("#0").attr("class","incorrect");
    }
</script>

Programmatically navigate using React router

For React Router v4+

Assuming that you won't be needing to navigate during the initial render itself (for which you can use <Redirect> component), this is what we are doing in our app.

Define an empty route which returns null, this will allow you to get the access to the history object. You need to do this at the top level where your Router is defined.

Now you can do all the things that can be done on history like history.push(), history.replace(), history.go(-1) etc!

import React from 'react';
import { HashRouter, Route } from 'react-router-dom';

let routeHistory = null;

export function navigateTo(path) {
  if(routeHistory !== null) {
    routeHistory.push(path);
  }
}

export default function App(props) {
  return (
    <HashRouter hashType="noslash">
      <Route
        render={({ history }) => {
          routeHistory = history;
          return null;
        }}
      />
      {/* Rest of the App */}
    </HashRouter>
  );
}

How can I use jQuery to move a div across the screen

Just a quick little function I drummed up that moves DIVs from their current spot to a target spot, one pixel step at a time. I tried to comment as best as I could, but the part you're interested in, is in example 1 and example 2, right after [$(function() { // jquery document.ready]. Put your bounds checking code there, and then exit the interval if conditions are met. Requires jQuery.

First the Demo: http://jsfiddle.net/pnYWY/

First the DIVs...

<style>
  .moveDiv {
    position:absolute;
    left:20px;
    top:20px;
    width:10px;
    height:10px;
    background-color:#ccc;
  }

  .moveDivB {
    position:absolute;
    left:20px;
    top:20px;
    width:10px;
    height:10px;
    background-color:#ccc;
  }
</style>


<div class="moveDiv"></div>
<div class="moveDivB"></div>

example 1) Start

// first animation (fire right away)
var myVar = setInterval(function(){
    $(function() { // jquery document.ready

        // returns true if it just took a step
        // returns false if the div has arrived
        if( !move_div_step(55,25,'.moveDiv') )
        {
            // arrived...
            console.log('arrived'); 
            clearInterval(myVar);
        }

    });
},50); // set speed here in ms for your delay

example 2) Delayed Start

// pause and then fire an animation..
setTimeout(function(){
    var myVarB = setInterval(function(){
        $(function() { // jquery document.ready
            // returns true if it just took a step
            // returns false if the div has arrived
            if( !move_div_step(25,55,'.moveDivB') )
            {
                // arrived...
                console.log('arrived'); 
                clearInterval(myVarB);
            }
        });
    },50); // set speed here in ms for your delay
},5000);// set speed here for delay before firing

Now the Function:

function move_div_step(xx,yy,target) // takes one pixel step toward target
{
    // using a line algorithm to move a div one step toward a given coordinate.
    var div_target = $(target);

    // get current x and current y
    var x = div_target.position().left; // offset is relative to document; position() is relative to parent;
    var y = div_target.position().top;

    // if x and y are = to xx and yy (destination), then div has arrived at it's destination.
    if(x == xx && y == yy)
        return false;

    // find the distances travelled
    var dx = xx - x;
    var dy = yy - y;

    // preventing time travel
    if(dx < 0)          dx *= -1;
    if(dy < 0)          dy *= -1;

    // determine speed of pixel travel...
    var sx=1, sy=1;

    if(dx > dy)         sy = dy/dx;
    else if(dy > dx)    sx = dx/dy;

    // find our one...
    if(sx == sy) // both are one..
    {
        if(x <= xx) // are we going forwards?
        {
            x++; y++;
        }
        else  // .. we are going backwards.
        {
            x--; y--;
        }       
    }
    else if(sx > sy) // x is the 1
    {
        if(x <= xx) // are we going forwards..?
            x++;
        else  // or backwards?
            x--;

        y += sy;
    }
    else if(sy > sx) // y is the 1 (eg: for every 1 pixel step in the y dir, we take 0.xxx step in the x
    {
        if(y <= yy) // going forwards?
            y++;
        else  // .. or backwards?
            y--;

        x += sx;
    }

    // move the div
    div_target.css("left", x);
    div_target.css("top",  y);

    return true;
}  // END :: function move_div_step(xx,yy,target)

How to add a delay for a 2 or 3 seconds

For 2.3 seconds you should do:

System.Threading.Thread.Sleep(2300);

Difference between drop table and truncate table?

I think you means the difference between DELETE TABLE and TRUNCATE TABLE.

DROP TABLE

remove the table from the database.

DELETE TABLE

without a condition delete all rows. If there are trigger and references then this will process for every row. Also a index will be modify if there one.

TRUNCATE TABLE

set the row count zero and without logging each row. That it is many faster as the other both.

SQL Query for Logins

Starting with SQL 2008, you should use sys.server_principals instead of sys.syslogins, which has been deprecated.

How do I restart my C# WinForm Application?

A much simpler approach that worked for me is:

Application.Restart();
Environment.Exit(0);

This preserves the command-line arguments and works despite event handlers that would normally prevent the application from closing.

The Restart() call tries to exit, starts a new instance anyway and returns. The Exit() call then terminates the process without giving any event handlers a chance to run. There is a very brief period in which both processes are running, which is not a problem in my case, but maybe in other cases.

The exit code 0 in Environment.Exit(0); specifies a clean shutdown. You can also exit with 1 to specify an error occurred.

Unable to capture screenshot. Prevented by security policy. Galaxy S6. Android 6.0

You must have either disabled, froze or uninstalled FaceProvider in settings>applications>all
This will only happen if it's frozen, either uninstall it, or enable it.

How to start Spyder IDE on Windows

Open a command prompt. Enter the command spyder. Does anything appear? If an exception is preventing it from opening, you would be able to see the reason here. If the command is not found, update your environment variables to point to the Python3.6/Scripts folder, and run spyder again (in a new cmd prompt).

How to delete an object by id with entity framework

This answer is actually taken from Scott Allen's course titled ASP.NET MVC 5 Fundamentals. I thought I'd share because I think it is slightly simpler and more intuitive than any of the answers here already. Also note according to Scott Allen and other trainings I've done, find method is an optimized way to retrieve a resource from database that can use caching if it already has been retrieved. In this code, collection refers to a DBSet of objects. Object can be any generic object type.

        var object = context.collection.Find(id);  
        context.collection.Remove(object);
        context.SaveChanges();

Help needed with Median If in Excel

Make a third column that has values like:

=IF(A1="Airline",B1)

=IF(A2="Airline",B2) etc

Then just perform a median on the new column.

How to display HTML tags as plain text

You can use htmlentities when echoing to the browser, this will show the tag rather than have html interpret it.

See here http://uk3.php.net/manual/en/function.htmlentities.php

Example:

 echo htmlentities("<strong>Look just like this line - so then know how to type it</strong>"); 

Output:

<strong>Look just like this line - so then know how to type it</strong>

Get local IP address in Node.js

Here is a multi-IP address version of jhurliman's answer:

function getIPAddresses() {

    var ipAddresses = [];

    var interfaces = require('os').networkInterfaces();
    for (var devName in interfaces) {
        var iface = interfaces[devName];
        for (var i = 0; i < iface.length; i++) {
            var alias = iface[i];
            if (alias.family === 'IPv4' && alias.address !== '127.0.0.1' && !alias.internal) {
                ipAddresses.push(alias.address);
            }
        }
    }
    return ipAddresses;
}

How to use Servlets and Ajax?

The right way to update the page currently displayed in the user's browser (without reloading it) is to have some code executing in the browser update the page's DOM.

That code is typically javascript that is embedded in or linked from the HTML page, hence the AJAX suggestion. (In fact, if we assume that the updated text comes from the server via an HTTP request, this is classic AJAX.)

It is also possible to implement this kind of thing using some browser plugin or add-on, though it may be tricky for a plugin to reach into the browser's data structures to update the DOM. (Native code plugins normally write to some graphics frame that is embedded in the page.)

Display loading image while post with ajax

$.ajax(
{
    type: 'post',
    url: 'mail.php',
    data: form.serialize(),
    beforeSend: function()
    {
        $('.content').html('loading...');
    },
    success: function(data)
    {
        $('.content').html(data);
    },
    error: function()
    {
        $('.content').html('error');
    }
});

have fun playing arround!

if you should have quick loading times which prevent te loading showing, you can add a timeout of some sort.

Creating a JSON dynamically with each input value using jquery

same from above example - if you are just looking for json (not an array of object) just use

function getJsonDetails() {
      item = {}
      item ["token1"] = token1val;
      item ["token2"] = token1val;
      return item;
}
console.log(JSON.stringify(getJsonDetails()))

this output ll print as (a valid json)

{ 
   "token1":"samplevalue1",
   "token2":"samplevalue2"
}

How to define a List bean in Spring?

Here is one method:

<bean id="stage1" class="Stageclass"/>
<bean id="stage2" class="Stageclass"/>

<bean id="stages" class="java.util.ArrayList">
    <constructor-arg>
        <list>
            <ref bean="stage1" />
            <ref bean="stage2" />                
        </list>
    </constructor-arg>
</bean>

Easy way to use variables of enum types as string in C?

The technique from Making something both a C identifier and a string? can be used here.

As usual with such preprocessor stuff, writing and understanding the preprocessor part can be hard, and includes passing macros to other macros and involves using # and ## operators, but using it is real easy. I find this style very useful for long enums, where maintaining the same list twice can be really troublesome.

Factory code - typed only once, usually hidden in the header:

enumFactory.h:

// expansion macro for enum value definition
#define ENUM_VALUE(name,assign) name assign,

// expansion macro for enum to string conversion
#define ENUM_CASE(name,assign) case name: return #name;

// expansion macro for string to enum conversion
#define ENUM_STRCMP(name,assign) if (!strcmp(str,#name)) return name;

/// declare the access function and define enum values
#define DECLARE_ENUM(EnumType,ENUM_DEF) \
  enum EnumType { \
    ENUM_DEF(ENUM_VALUE) \
  }; \
  const char *GetString(EnumType dummy); \
  EnumType Get##EnumType##Value(const char *string); \

/// define the access function names
#define DEFINE_ENUM(EnumType,ENUM_DEF) \
  const char *GetString(EnumType value) \
  { \
    switch(value) \
    { \
      ENUM_DEF(ENUM_CASE) \
      default: return ""; /* handle input error */ \
    } \
  } \
  EnumType Get##EnumType##Value(const char *str) \
  { \
    ENUM_DEF(ENUM_STRCMP) \
    return (EnumType)0; /* handle input error */ \
  } \

Factory used

someEnum.h:

#include "enumFactory.h"
#define SOME_ENUM(XX) \
    XX(FirstValue,) \
    XX(SecondValue,) \
    XX(SomeOtherValue,=50) \
    XX(OneMoreValue,=100) \

DECLARE_ENUM(SomeEnum,SOME_ENUM)

someEnum.cpp:

#include "someEnum.h"
DEFINE_ENUM(SomeEnum,SOME_ENUM)

The technique can be easily extended so that XX macros accepts more arguments, and you can also have prepared more macros to substitute for XX for different needs, similar to the three I have provided in this sample.

Comparison to X-Macros using #include / #define / #undef

While this is similar to X-Macros others have mentioned, I think this solution is more elegant in that it does not require #undefing anything, which allows you to hide more of the complicated stuff is in the factory the header file - the header file is something you are not touching at all when you need to define a new enum, therefore new enum definition is a lot shorter and cleaner.

Does a "Find in project..." feature exist in Eclipse IDE?

Ctrl + H is the best way! Remember to copy the string before you start searching!

Exit a while loop in VBS/VBA

I know this is old as dirt but it ranked pretty high in google.

The problem with the solution maddy implemented (in response to rahul) to maintain the use of a While...Wend loop has some drawbacks

In the example given

num = 0
While num < 10
  If status = "Fail" Then
    num = 10
  End If
  num = num + 1
Wend

After status = "Fail" num will actually equal 11. The loop didn't end on the fail condition, it ends on the next test. All of the code after the check still processed and your counter is not what you might have expected it to be.

Now depending on what you are all doing in your loop it may not matter, but then again if your code looked something more like:

num = 0
While num < 10
  If folder = "System32" Then
    num = 10
  End If
  RecursiveDeleteFunction folder
  num = num + 1
Wend

Using Do While or Do Until allows you to stop execution of the loop using Exit Do instead of using trickery with your loop condition to maintain the While ... Wend syntax. I would recommend using that instead.

How to convert Calendar to java.sql.Date in Java?

Calendar cal = Calendar.getInstance(); //This to obtain today's date in our Calendar var.

java.sql.Date date = new Date (cal.getTimeInMillis());

What are the specific differences between .msi and setup.exe file?

.msi files are windows installer files without the windows installer runtime, setup.exe can be any executable programm (probably one that installs stuff on your computer)

How do I find out what type each object is in a ArrayList<Object>?

Instanceof works if you don't depend on specific classes, but also keep in mind that you can have nulls in the list, so obj.getClass() will fail, but instanceof always returns false on null.

Git branching: master vs. origin/master vs. remotes/origin/master

Technically there aren't actually any "remote" things at all1 in your Git repo, there are just local names that should correspond to the names on another, different repo. The ones named origin/whatever will initially match up with those on the repo you cloned-from:

git clone ssh://some.where.out.there/some/path/to/repo # or git://some.where...

makes a local copy of the other repo. Along the way it notes all the branches that were there, and the commits those refer-to, and sticks those into your local repo under the names refs/remotes/origin/.

Depending on how long you go before you git fetch or equivalent to update "my copy of what's some.where.out.there", they may change their branches around, create new ones, and delete some. When you do your git fetch (or git pull which is really fetch plus merge), your repo will make copies of their new work and change all the refs/remotes/origin/<name> entries as needed. It's that moment of fetching that makes everything match up (well, that, and the initial clone, and some cases of pushing too—basically whenever Git gets a chance to check—but see caveat below).

Git normally has you refer to your own refs/heads/<name> as just <name>, and the remote ones as origin/<name>, and it all just works because it's obvious which one is which. It's sometimes possible to create your own branch names that make it not obvious, but don't worry about that until it happens. :-) Just give Git the shortest name that makes it obvious, and it will go from there: origin/master is "where master was over there last time I checked", and master is "where master is over here based on what I have been doing". Run git fetch to update Git on "where master is over there" as needed.


Caveat: in versions of Git older than 1.8.4, git fetch has some modes that don't update "where master is over there" (more precisely, modes that don't update any remote-tracking branches). Running git fetch origin, or git fetch --all, or even just git fetch, does update. Running git fetch origin master doesn't. Unfortunately, this "doesn't update" mode is triggered by ordinary git pull. (This is mainly just a minor annoyance and is fixed in Git 1.8.4 and later.)


1Well, there is one thing that is called a "remote". But that's also local! The name origin is the thing Git calls "a remote". It's basically just a short name for the URL you used when you did the clone. It's also where the origin in origin/master comes from. The name origin/master is called a remote-tracking branch, which sometimes gets shortened to "remote branch", especially in older or more informal documentation.

How to connect to Oracle 11g database remotely

Its quite easy on computer a you don't need to do anything just make sure both system are on same network if its not internet access(for this you need static ip). Okay now on computer b go to start menu find configuration under oracle folder click Net Configuration Assistant under that folder when window pop up click Local net configuration option it must be third option.

Now click add and click next in next screen it will ask service name here you need to add oracle global database name of computer A(Normally I use oracle86 for my installation) now click next next screen choose protocol normally its tcp click next in host name enter computer A's name you can found that in my computer properties. Click next don't change port untill you have changed that in Computer A click next and choose test connection now here you can check your connection working or not if the error is username and password not correct then click login credential button and fill correct username and password. If its saying unable to reach computer ot target not found than you must add exception in firewall for 1521 port or just disable firewall on computer A.

Programmatically navigate to another view controller/scene

If you want to navigate to Controller created Programmatically, then do this:

let newViewController = NewViewController()
self.navigationController?.pushViewController(newViewController, animated: true)

If you want to navigate to Controller on StoryBoard with Identifier "newViewController", then do this:

let storyBoard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let newViewController = storyBoard.instantiateViewController(withIdentifier: "newViewController") as! NewViewController
        self.present(newViewController, animated: true, completion: nil)

What are the undocumented features and limitations of the Windows FINDSTR command?

FINDSTR has a color bug that I described and solved at https://superuser.com/questions/1535810/is-there-a-better-way-to-mitigate-this-obscure-color-bug-when-piping-to-findstr/1538802?noredirect=1#comment2339443_1538802

To summarize that thread, the bug is that if input is piped to FINDSTR within a parenthesized block of code, inline ANSI escape colorcodes stop working in commands executed later. An example of inline colorcodes is: echo %magenta%Alert: Something bad happened%yellow% (where magenta and yellow are vars defined earlier in the .bat file as the corresponding ANSI escape colorcodes).

My initial solution was to call a do-nothing subroutine after the FINDSTR. Somehow the call or the return "resets" whatever needs to be reset.

Later I discovered another solution that presumably is more efficient: place the FINDSTR phrase within parentheses, as in the following example: echo success | ( FINDSTR /R success ) Placing the FINDSTR phrase within a nested block of code appears to isolate FINDSTR's colorcode bug so it won't affect what's outside the nested block. Perhaps this technique will solve some other undesired FINDSTR side effects too.

Tooltip on image

You can use the following format to generate a tooltip for an image.

<div class="tooltip"><img src="joe.jpg" />
  <span class="tooltiptext">Tooltip text</span>
</div>

How to change Rails 3 server default port in develoment?

If you're using puma (I'm using this on Rails 6+):

To change default port for all environments:

The "{3000}" part sets the default port if undefined in ENV.

~/config/puma.rb

change:
    port ENV.fetch('PORT') { 3000 }
for:
    port ENV.fetch('PORT') { 10524 }

To define it depending on the environment, using Figaro gem for credentials/environment variable:

~/application.yml
local_db_username: your_user_name
?local_db_password: your_password
PORT: 10524

You can adapt this to you own environment variable manager.

How to get all key in JSON object (javascript)

var input = {"document":
  {"people":[
    {"name":["Harry Potter"],"age":["18"],"gender":["Male"]},
    {"name":["hermione granger"],"age":["18"],"gender":["Female"]},
  ]}
}

var keys = [];
for(var i = 0;i<input.document.people.length;i++)
{
    Object.keys(input.document.people[i]).forEach(function(key){
        if(keys.indexOf(key) == -1)
        {
            keys.push(key);
        }
    });
}
console.log(keys);

Make new column in Panda dataframe by adding values from other columns

As of Pandas version 0.16.0 you can use assign as follows:

df = pd.DataFrame({"A": [1,2,3], "B": [4,6,9]})
df.assign(C = df.A + df.B)

# Out[383]: 
#    A  B   C
# 0  1  4   5
# 1  2  6   8
# 2  3  9  12

You can add multiple columns this way as follows:

df.assign(C = df.A + df.B,
          Diff = df.B - df.A,
          Mult = df.A * df.B)
# Out[379]: 
#    A  B   C  Diff  Mult
# 0  1  4   5     3     4
# 1  2  6   8     4    12
# 2  3  9  12     6    27

Controlling number of decimal digits in print output in R

If you are producing the entire output yourself, you can use sprintf(), e.g.

> sprintf("%.10f",0.25)
[1] "0.2500000000"

specifies that you want to format a floating point number with ten decimal points (in %.10f the f is for float and the .10 specifies ten decimal points).

I don't know of any way of forcing R's higher level functions to print an exact number of digits.

Displaying 100 digits does not make sense if you are printing R's usual numbers, since the best accuracy you can get using 64-bit doubles is around 16 decimal digits (look at .Machine$double.eps on your system). The remaining digits will just be junk.

The equivalent of a GOTO in python

I entirely agree that goto is poor poor coding, but no one has actually answered the question. There is in fact a goto module for Python (though it was released as an April fool joke and is not recommended to be used, it does work).

How does one extract each folder name from a path?

The quick answer is to use the .Split('\\') method.

HTML5 placeholder css padding

line-height: normal; 

worked for me ;)

How to animate the change of image in an UIImageView?

Swift 5:

When deal with collectionView. Reloading only 1 item or several items with animation. I try some different animation options when changing cell image, no difference, so I don't indicate animation name here.

UIView.animate(withDuration: 1.0) { [weak self] in
                guard let self = self else { return print("gotchya!") }
                self.collectionView.reloadItems(at: [indexPath])
            }

How to reset Jenkins security settings from the command line?

The simplest solution is to completely disable security - change true to false in /var/lib/jenkins/config.xml file.

<useSecurity>true</useSecurity>

Then just restart Jenkins, by

sudo service jenkins restart

And then go to admin panel and set everything once again.

If you in case are running your Jenkins inside k8s pod from a docker, which is my case and can not run service command, then you can just restart Jenkins by deleting the pod:

kubectl delete pod <jenkins-pod-name>

Once the command was issued, the k8s will terminate the old pod and start a new one.

WooCommerce - get category for product page

I literally striped out this line of code from content-single-popup.php located in woocommerce folder in my theme directory.

global $product; 
echo $product->get_categories( ', ', ' ' . _n( ' ', '  ', $cat_count, 'woocommerce' ) . ' ', ' ' );

Since my theme that I am working on has integrated woocommerce in it, this was my solution.

Set background color of WPF Textbox in C# code

Have you taken a look at Color.FromRgb?

Java, List only subdirectories from a directory, not files

Here is solution for my code. I just did a litlle change from first answer. This will list all folders only in desired directory line by line:

try {
            File file = new File("D:\\admir\\MyBookLibrary");
            String[] directories = file.list(new FilenameFilter() {
              @Override
              public boolean accept(File current, String name) {
                return new File(current, name).isDirectory();
              }
            });
            for(int i = 0;i < directories.length;i++) {
                if(directories[i] != null) {
                    System.out.println(Arrays.asList(directories[i]));

                }
            }
        }catch(Exception e) {
            System.err.println("Error!");
        }

Could not create work tree dir 'example.com'.: Permission denied

Turns out the problem was in the permission. I fix it with the following command

sudo chown -R $USER /var/www

Please make sure with the $USER variable. I tested and worked on Ubuntu Distro

Tainted canvases may not be exported

I resolved the problem using useCORS: true option

 html2canvas(document.getElementsByClassName("droppable-area")[0], { useCORS:true}).then(function (canvas){
        var imgBase64 = canvas.toDataURL();
        // console.log("imgBase64:", imgBase64);
        var imgURL = "data:image/" + imgBase64;
        var triggerDownload = $("<a>").attr("href", imgURL).attr("download", "layout_"+new Date().getTime()+".jpeg").appendTo("body");
        triggerDownload[0].click();
        triggerDownload.remove();
    });

How can I truncate a string to the first 20 words in PHP?

Something like this could probably do the trick:

<?php 
$words = implode(' ', array_slice(split($input, ' ', 21), 0, 20));

How to give spacing between buttons using bootstrap

HTML:

<input id="id_ok" class="btn btn-space" value="OK" type="button">
<input id="id_cancel" class="btn btn-space" value="Cancel" type="button">

CSS:

.btn-space {
    margin-right: 5px;
}

LINQ syntax where string value is not null or empty

http://connect.microsoft.com/VisualStudio/feedback/ViewFeedback.aspx?FeedbackID=367077

Problem Statement
It's possible to write LINQ to SQL that gets all rows that have either null or an empty string in a given field, but it's not possible to use string.IsNullOrEmpty to do it, even though many other string methods map to LINQ to SQL. Proposed Solution Allow string.IsNullOrEmpty in a LINQ to SQL where clause so that these two queries have the same result:

var fieldNullOrEmpty =
from item in db.SomeTable
where item.SomeField == null || item.SomeField.Equals(string.Empty)
select item;

var fieldNullOrEmpty2 =
from item in db.SomeTable
where string.IsNullOrEmpty(item.SomeField)
select item;

Other Reading:
1. DevArt
2. Dervalp.com
3. StackOverflow Post

How does Java resolve a relative path in new File()?

I went off of peter.petrov's answer but let me explain where you make the file edits to change it to a relative path.

Simply edit "AXLAPIService.java" and change

url = new URL("file:C:users..../schema/current/AXLAPI.wsdl");

to

url = new URL("file:./schema/current/AXLAPI.wsdl");

or where ever you want to store it.

You can still work on packaging the wsdl file into the meta-inf folder in the jar but this was the simplest way to get it working for me.

Convert Rows to columns using 'Pivot' in SQL Server

I've achieved the same thing before by using subqueries. So if your original table was called StoreCountsByWeek, and you had a separate table that listed the Store IDs, then it would look like this:

SELECT StoreID, 
    Week1=(SELECT ISNULL(SUM(xCount),0) FROM StoreCountsByWeek WHERE StoreCountsByWeek.StoreID=Store.StoreID AND Week=1),
    Week2=(SELECT ISNULL(SUM(xCount),0) FROM StoreCountsByWeek WHERE StoreCountsByWeek.StoreID=Store.StoreID AND Week=2),
    Week3=(SELECT ISNULL(SUM(xCount),0) FROM StoreCountsByWeek WHERE StoreCountsByWeek.StoreID=Store.StoreID AND Week=3)
FROM Store
ORDER BY StoreID

One advantage to this method is that the syntax is more clear and it makes it easier to join to other tables to pull other fields into the results too.

My anecdotal results are that running this query over a couple of thousand rows completed in less than one second, and I actually had 7 subqueries. But as noted in the comments, it is more computationally expensive to do it this way, so be careful about using this method if you expect it to run on large amounts of data .

Https to http redirect using htaccess

RewriteCond %{HTTP:X-Forwarded-Proto} =https

wkhtmltopdf: cannot connect to X server

for 14.04.1-Ubuntu https://wkhtmltopdf.org/downloads.html

wget https://downloads.wkhtmltopdf.org/0.12/0.12.4/wkhtmltox-0.12.4_linux-generic-amd64.tar.xz -O mktemp.tar.xz
tar xf mktemp.tar.xz
sudo cp wkhtmltox/bin/wkhtmltopdf /usr/bin/wkhtmltopdf
sudo chmod +x /usr/bin/wkhtmltopdf
rm mktemp.tar.xz
rm wkhtmltox -rf
apt-get update
apt-get install -y libxrender1 libxtst6 libxi6
wkhtmltopdf http://www.google.com test.pdf

How to downgrade tensorflow, multiple versions possible?

Pip allows to specify the version

pip install tensorflow==1.1

Remove all spaces from a string in SQL Server

Simply replace it;

SELECT REPLACE(fld_or_variable, ' ', '')

Edit: Just to clarify; its a global replace, there is no need to trim() or worry about multiple spaces for either char or varchar:

create table #t (
    c char(8),
    v varchar(8))

insert #t (c, v) values 
    ('a a'    , 'a a'    ),
    ('a a  '  , 'a a  '  ),
    ('  a a'  , '  a a'  ),
    ('  a a  ', '  a a  ')

select
    '"' + c + '"' [IN], '"' + replace(c, ' ', '') + '"' [OUT]
from #t  
union all select
    '"' + v + '"', '"' + replace(v, ' ', '') + '"'
from #t 

Result

IN             OUT
===================
"a a     "     "aa"
"a a     "     "aa"
"  a a   "     "aa"
"  a a   "     "aa"
"a a"          "aa"
"a a  "        "aa"
"  a a"        "aa"
"  a a  "      "aa"

What's the difference between an Angular component and module

Component is the template(view) + a class (Typescript code) containing some logic for the view + metadata(to tell angular about from where to get data it needs to display the template).

Modules basically group the related components, services together so that you can have chunks of functionality which can then run independently. For example, an app can have modules for features, for grouping components for a particular feature of your app, such as a dashboard, which you can simply grab and use inside another application.

'git' is not recognized as an internal or external command

;C:\Program Files (x86)\Git\bin;C:\Program Files (x86)\Git\cmd

add above path in environment variables

note: path may differ but you should add both bin and cmd

How to log cron jobs?

By default cron logs to /var/log/syslog so you can see cron related entries by using:

grep CRON /var/log/syslog

https://askubuntu.com/questions/56683/where-is-the-cron-crontab-log

How are environment variables used in Jenkins with Windows Batch Command?

I know nothing about Jenkins, but it looks like you are trying to access environment variables using some form of unix syntax - that won't work.

If the name of the variable is WORKSPACE, then the value is expanded in Windows batch using
%WORKSPACE%. That form of expansion is performed at parse time. For example, this will print to screen the value of WORKSPACE

echo %WORKSPACE%

If you need the value at execution time, then you need to use delayed expansion !WORKSPACE!. Delayed expansion is not normally enabled by default. Use SETLOCAL EnableDelayedExpansion to enable it. Delayed expansion is often needed because blocks of code within parentheses and/or multiple commands concatenated by &, &&, or || are parsed all at once, so a value assigned within the block cannot be read later within the same block unless you use delayed expansion.

setlocal enableDelayedExpansion
set WORKSPACE=BEFORE
(
  set WORKSPACE=AFTER
  echo Normal Expansion = %WORKSPACE%
  echo Delayed Expansion = !WORKSPACE!
)

The output of the above is

Normal Expansion = BEFORE
Delayed Expansion = AFTER

Use HELP SET or SET /? from the command line to get more information about Windows environment variables and the various expansion options. For example, it explains how to do search/replace and substring operations.

Rename Excel Sheet with VBA Macro

Suggest you add handling to test if any of the sheets to be renamed already exist:

Sub Test()

Dim ws As Worksheet
Dim ws1 As Worksheet
Dim strErr As String

On Error Resume Next
For Each ws In ActiveWorkbook.Sheets
Set ws1 = Sheets(ws.Name & "_v1")
    If ws1 Is Nothing Then
        ws.Name = ws.Name & "_v1"
    Else
         strErr = strErr & ws.Name & "_v1" & vbNewLine
    End If
Set ws1 = Nothing
Next
On Error GoTo 0

If Len(strErr) > 0 Then MsgBox strErr, vbOKOnly, "these sheets already existed"

End Sub

Converting a float to a string without rounding it

Some form of rounding is often unavoidable when dealing with floating point numbers. This is because numbers that you can express exactly in base 10 cannot always be expressed exactly in base 2 (which your computer uses).

For example:

>>> .1
0.10000000000000001

In this case, you're seeing .1 converted to a string using repr:

>>> repr(.1)
'0.10000000000000001'

I believe python chops off the last few digits when you use str() in order to work around this problem, but it's a partial workaround that doesn't substitute for understanding what's going on.

>>> str(.1)
'0.1'

I'm not sure exactly what problems "rounding" is causing you. Perhaps you would do better with string formatting as a way to more precisely control your output?

e.g.

>>> '%.5f' % .1
'0.10000'
>>> '%.5f' % .12345678
'0.12346'

Documentation here.

PHP errors NOT being displayed in the browser [Ubuntu 10.10]

Don't just enable the first occurrence of display_errors in the php.ini file. Make sure you scroll down to the "real" setting and change it from Off to On.

The thing is that if you settle with changing (i.e. uncomment + add = On) by the very first occurrence of display_errors your changes will be overwritten somewhere on line 480 where it's set to Off again.

How to change ReactJS styles dynamically?

Ok, finally found the solution.

Probably due to lack of experience with ReactJS and web development...

    var Task = React.createClass({
    render: function() {
      var percentage = this.props.children + '%';
      ....
        <div className="ui-progressbar-value ui-widget-header ui-corner-left" style={{width : percentage}}/>
      ...

I created the percentage variable outside in the render function.

TestNG ERROR Cannot find class in classpath

Check the class hierarchy. If the package is missing in your class you'll get this error. So, try to create a new testing class by selecting the package.

How to override application.properties during production in Spring-Boot?

The spring configuration precedence is as follows.

  1. ServletConfig init Parameter
  2. ServletContext init parameter
  3. JNDI attributes
  4. System.getProperties()

So your configuration will be overridden at the command-line if you wish to do that. But the recommendation is to avoid overriding, though you can use multiple profiles.

MySQL Calculate Percentage

try this

   SELECT group_name, employees, surveys, COUNT( surveys ) AS test1, 
        concat(round(( surveys/employees * 100 ),2),'%') AS percentage
    FROM a_test
    GROUP BY employees

DEMO HERE

Using local makefile for CLion instead of CMake

Currently, only CMake is supported by CLion. Others build systems will be added in the future, but currently, you can only use CMake.

An importer tool has been implemented to help you to use CMake.

Edit:

Source : http://blog.jetbrains.com/clion/2014/09/clion-answers-frequently-asked-questions/

HashSet vs. List performance

Just thought I'd chime in with some benchmarks for different scenarios to illustrate the previous answers:

  1. A few (12 - 20) small strings (length between 5 and 10 characters)
  2. Many (~10K) small strings
  3. A few long strings (length between 200 and 1000 characters)
  4. Many (~5K) long strings
  5. A few integers
  6. Many (~10K) integers

And for each scenario, looking up values which appear:

  1. In the beginning of the list ("start", index 0)
  2. Near the beginning of the list ("early", index 1)
  3. In the middle of the list ("middle", index count/2)
  4. Near the end of the list ("late", index count-2)
  5. At the end of the list ("end", index count-1)

Before each scenario I generated randomly sized lists of random strings, and then fed each list to a hashset. Each scenario ran 10,000 times, essentially:

(test pseudocode)

stopwatch.start
for X times
    exists = list.Contains(lookup);
stopwatch.stop

stopwatch.start
for X times
    exists = hashset.Contains(lookup);
stopwatch.stop

Sample Output

Tested on Windows 7, 12GB Ram, 64 bit, Xeon 2.8GHz

---------- Testing few small strings ------------
Sample items: (16 total)
vgnwaloqf diwfpxbv tdcdc grfch icsjwk
...

Benchmarks:
1: hashset: late -- 100.00 % -- [Elapsed: 0.0018398 sec]
2: hashset: middle -- 104.19 % -- [Elapsed: 0.0019169 sec]
3: hashset: end -- 108.21 % -- [Elapsed: 0.0019908 sec]
4: list: early -- 144.62 % -- [Elapsed: 0.0026607 sec]
5: hashset: start -- 174.32 % -- [Elapsed: 0.0032071 sec]
6: list: middle -- 187.72 % -- [Elapsed: 0.0034536 sec]
7: list: late -- 192.66 % -- [Elapsed: 0.0035446 sec]
8: list: end -- 215.42 % -- [Elapsed: 0.0039633 sec]
9: hashset: early -- 217.95 % -- [Elapsed: 0.0040098 sec]
10: list: start -- 576.55 % -- [Elapsed: 0.0106073 sec]


---------- Testing many small strings ------------
Sample items: (10346 total)
dmnowa yshtrxorj vthjk okrxegip vwpoltck
...

Benchmarks:
1: hashset: end -- 100.00 % -- [Elapsed: 0.0017443 sec]
2: hashset: late -- 102.91 % -- [Elapsed: 0.0017951 sec]
3: hashset: middle -- 106.23 % -- [Elapsed: 0.0018529 sec]
4: list: early -- 107.49 % -- [Elapsed: 0.0018749 sec]
5: list: start -- 126.23 % -- [Elapsed: 0.0022018 sec]
6: hashset: early -- 134.11 % -- [Elapsed: 0.0023393 sec]
7: hashset: start -- 372.09 % -- [Elapsed: 0.0064903 sec]
8: list: middle -- 48,593.79 % -- [Elapsed: 0.8476214 sec]
9: list: end -- 99,020.73 % -- [Elapsed: 1.7272186 sec]
10: list: late -- 99,089.36 % -- [Elapsed: 1.7284155 sec]


---------- Testing few long strings ------------
Sample items: (19 total)
hidfymjyjtffcjmlcaoivbylakmqgoiowbgxpyhnrreodxyleehkhsofjqenyrrtlphbcnvdrbqdvji...
...

Benchmarks:
1: list: early -- 100.00 % -- [Elapsed: 0.0018266 sec]
2: list: start -- 115.76 % -- [Elapsed: 0.0021144 sec]
3: list: middle -- 143.44 % -- [Elapsed: 0.0026201 sec]
4: list: late -- 190.05 % -- [Elapsed: 0.0034715 sec]
5: list: end -- 193.78 % -- [Elapsed: 0.0035395 sec]
6: hashset: early -- 215.00 % -- [Elapsed: 0.0039271 sec]
7: hashset: end -- 248.47 % -- [Elapsed: 0.0045386 sec]
8: hashset: start -- 298.04 % -- [Elapsed: 0.005444 sec]
9: hashset: middle -- 325.63 % -- [Elapsed: 0.005948 sec]
10: hashset: late -- 431.62 % -- [Elapsed: 0.0078839 sec]


---------- Testing many long strings ------------
Sample items: (5000 total)
yrpjccgxjbketcpmnvyqvghhlnjblhgimybdygumtijtrwaromwrajlsjhxoselbucqualmhbmwnvnpnm
...

Benchmarks:
1: list: early -- 100.00 % -- [Elapsed: 0.0016211 sec]
2: list: start -- 132.73 % -- [Elapsed: 0.0021517 sec]
3: hashset: start -- 231.26 % -- [Elapsed: 0.003749 sec]
4: hashset: end -- 368.74 % -- [Elapsed: 0.0059776 sec]
5: hashset: middle -- 385.50 % -- [Elapsed: 0.0062493 sec]
6: hashset: late -- 406.23 % -- [Elapsed: 0.0065854 sec]
7: hashset: early -- 421.34 % -- [Elapsed: 0.0068304 sec]
8: list: middle -- 18,619.12 % -- [Elapsed: 0.3018345 sec]
9: list: end -- 40,942.82 % -- [Elapsed: 0.663724 sec]
10: list: late -- 41,188.19 % -- [Elapsed: 0.6677017 sec]


---------- Testing few ints ------------
Sample items: (16 total)
7266092 60668895 159021363 216428460 28007724
...

Benchmarks:
1: hashset: early -- 100.00 % -- [Elapsed: 0.0016211 sec]
2: hashset: end -- 100.45 % -- [Elapsed: 0.0016284 sec]
3: list: early -- 101.83 % -- [Elapsed: 0.0016507 sec]
4: hashset: late -- 108.95 % -- [Elapsed: 0.0017662 sec]
5: hashset: middle -- 112.29 % -- [Elapsed: 0.0018204 sec]
6: hashset: start -- 120.33 % -- [Elapsed: 0.0019506 sec]
7: list: late -- 134.45 % -- [Elapsed: 0.0021795 sec]
8: list: start -- 136.43 % -- [Elapsed: 0.0022117 sec]
9: list: end -- 169.77 % -- [Elapsed: 0.0027522 sec]
10: list: middle -- 237.94 % -- [Elapsed: 0.0038573 sec]


---------- Testing many ints ------------
Sample items: (10357 total)
370826556 569127161 101235820 792075135 270823009
...

Benchmarks:
1: list: early -- 100.00 % -- [Elapsed: 0.0015132 sec]
2: hashset: end -- 101.79 % -- [Elapsed: 0.0015403 sec]
3: hashset: early -- 102.08 % -- [Elapsed: 0.0015446 sec]
4: hashset: middle -- 103.21 % -- [Elapsed: 0.0015618 sec]
5: hashset: late -- 104.26 % -- [Elapsed: 0.0015776 sec]
6: list: start -- 126.78 % -- [Elapsed: 0.0019184 sec]
7: hashset: start -- 130.91 % -- [Elapsed: 0.0019809 sec]
8: list: middle -- 16,497.89 % -- [Elapsed: 0.2496461 sec]
9: list: end -- 32,715.52 % -- [Elapsed: 0.4950512 sec]
10: list: late -- 33,698.87 % -- [Elapsed: 0.5099313 sec]

How to skip "are you sure Y/N" when deleting files in batch files

Add /Q for quiet mode and it should remove the prompt.

How do I combine two data-frames based on two columns?

See the documentation on ?merge, which states:

By default the data frames are merged on the columns with names they both have, 
 but separate specifications of the columns can be given by by.x and by.y.

This clearly implies that merge will merge data frames based on more than one column. From the final example given in the documentation:

x <- data.frame(k1=c(NA,NA,3,4,5), k2=c(1,NA,NA,4,5), data=1:5)
y <- data.frame(k1=c(NA,2,NA,4,5), k2=c(NA,NA,3,4,5), data=1:5)
merge(x, y, by=c("k1","k2")) # NA's match

This example was meant to demonstrate the use of incomparables, but it illustrates merging using multiple columns as well. You can also specify separate columns in each of x and y using by.x and by.y.

What should I use to open a url instead of urlopen in urllib3

You should use urllib.reuqest, not urllib3.

import urllib.request   # not urllib - important!
urllib.request.urlopen('https://...')

What is the simplest way to get indented XML with line breaks from XmlDocument?

As adapted from Erika Ehrli's blog, this should do it:

XmlDocument doc = new XmlDocument();
doc.LoadXml("<item><name>wrench</name></item>");
// Save the document to a file and auto-indent the output.
using (XmlTextWriter writer = new XmlTextWriter("data.xml", null)) {
    writer.Formatting = Formatting.Indented;
    doc.Save(writer);
}

Docker expose all ports or range of ports from 7000 to 8000

Since Docker 1.5 you can now expose a range of ports to other linked containers using:

The Dockerfile EXPOSE command:

EXPOSE 7000-8000

or The Docker run command:

docker run --expose=7000-8000

Or instead you can publish a range of ports to the host machine via Docker run command:

docker run -p 7000-8000:7000-8000

java create date object using a value string

try this, it worked for me.

 String inputString = "01-01-1900";
    Date inputDate= null;
    try {
        inputDate = new SimpleDateFormat("dd-MM-yyyy").parse(inputString);
    } catch (ParseException e) {
        e.printStackTrace();
    }

    dp.getDatePicker().setMinDate(inputDate.getTime());

How to set transparent background for Image Button in code?

If you want to use android R class

textView.setBackgroundColor(ContextCompat.getColor(getActivity(), android.R.color.transparent));

and don't forget to add support library to Gradle file

compile 'com.android.support:support-v4:23.3.0'

Set drawable size programmatically

Probably a little late. But here is the solution that finally worked for me in every situation.

The idea is to create a custom drawable with fixed intrinic size and pass the drawing job on to the original drawable.

Drawable icon = new ColorDrawable(){
        Drawable iconOrig = resolveInfo.loadIcon(packageManager);

        @Override
        public void setBounds(int left, int top, int right, int bottom){
            super.setBounds(left, top, right, bottom);//This is needed so that getBounds on this class would work correctly.
            iconOrig.setBounds(left, top, right, bottom);
        }

        @Override
        public void draw(Canvas canvas){
            iconOrig.draw(canvas);
        }

        @Override
        public int getIntrinsicWidth(){
            return  mPlatform.dp2px(30);
        }

        @Override
        public int getIntrinsicHeight(){
            return  mPlatform.dp2px(30);
        }
    };

Can you break from a Groovy "each" closure?

You could break by RETURN. For example

  def a = [1, 2, 3, 4, 5, 6, 7]
  def ret = 0
  a.each {def n ->
    if (n > 5) {
      ret = n
      return ret
    }
  }

It works for me!

Why does integer division in C# return an integer and not a float?

Since you don't use any suffix, the literals 13 and 4 are interpreted as integer:

Manual:

If the literal has no suffix, it has the first of these types in which its value can be represented: int, uint, long, ulong.

Thus, since you declare 13 as integer, integer division will be performed:

Manual:

For an operation of the form x / y, binary operator overload resolution is applied to select a specific operator implementation. The operands are converted to the parameter types of the selected operator, and the type of the result is the return type of the operator.

The predefined division operators are listed below. The operators all compute the quotient of x and y.

Integer division:

int operator /(int x, int y);
uint operator /(uint x, uint y);
long operator /(long x, long y);
ulong operator /(ulong x, ulong y);

And so rounding down occurs:

The division rounds the result towards zero, and the absolute value of the result is the largest possible integer that is less than the absolute value of the quotient of the two operands. The result is zero or positive when the two operands have the same sign and zero or negative when the two operands have opposite signs.

If you do the following:

int x = 13f / 4f;

You'll receive a compiler error, since a floating-point division (the / operator of 13f) results in a float, which cannot be cast to int implicitly.

If you want the division to be a floating-point division, you'll have to make the result a float:

float x = 13 / 4;

Notice that you'll still divide integers, which will implicitly be cast to float: the result will be 3.0. To explicitly declare the operands as float, using the f suffix (13f, 4f).

What's the difference between "2*2" and "2**2" in Python?

The top one is a "power" operator, so in this case it is the same as 2 * 2 equal to is 2 to the power of 2. If you put a 3 in the middle position, you will see a difference.

Can I make a function available in every controller in angular?

Though the first approach is advocated as 'the angular like' approach, I feel this adds overheads.

Consider if I want to use this myservice.foo function in 10 different controllers. I will have to specify this 'myService' dependency and then $scope.callFoo scope property in all ten of them. This is simply a repetition and somehow violates the DRY principle.

Whereas, if I use the $rootScope approach, I specify this global function gobalFoo only once and it will be available in all my future controllers, no matter how many.

How to redirect to another page using AngularJS?

I used the below code to redirect to new page

$window.location.href = '/foldername/page.html';

and injected $window object in my controller function.

convert from Color to brush

SolidColorBrush brush = new SolidColorBrush( Color.FromArgb(255,255,139,0) )

How to use `replace` of directive definition?

Also i got this error if i had the comment in tn top level of template among with the actual root element.

<!-- Just a commented out stuff -->
<div>test of {{value}}</div>

Setting Remote Webdriver to run tests in a remote computer using Java

By Default the InternetExplorerDriver listens on port "5555". Change your huburl to match that. you can look on the cmd box window to confirm.

C# How to determine if a number is a multiple of another?

Use the modulus (%) operator:

6 % 3 == 0
7 % 3 == 1

How to get box-shadow on left & right sides only

I tried to copy the bootstrap shadow-sm just in the right side, here is my code:

.shadow-rs{
    box-shadow: 5px 0 5px -4px rgba(237, 241, 235, 0.8);
}

What SOAP client libraries exist for Python, and where is the documentation for them?

I followed the advice of other answers to this question and gave SUDS a try. After using it "in anger" I must agree: SUDS is very nice! Highly recommended!

I did run into trouble calling HTTPS-based web services from behind a proxy. At the time of this writing, this affects all Python web-service clients that use urllib2, so I'll document the solution here.

The urllib2 module shipping with python 2.6.2 and below will not issue a CONNECT to the proxy for HTTPS-over-HTTP-proxy sessions. This results in a long timeout, or if you are lucky, an error that looks like:

abort: error: error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol

This was issue1424152 on the Python bug tracker. There are patches attached to the bug report that will fix this in Python 2.x and Python 3.x. The issue is already fixed.

Simple example of threading in C++

There is also a POSIX library for POSIX operating systems. Check for compatability

#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include <iostream>

void *task(void *argument){
      char* msg;
      msg = (char*)argument;
      std::cout<<msg<<std::endl;
}

int main(){
    pthread_t thread1, thread2;
    int i1,i2;
    i1 = pthread_create( &thread1, NULL, task, (void*) "thread 1");
    i2 = pthread_create( &thread2, NULL, task, (void*) "thread 2");

    pthread_join(thread1,NULL);
    pthread_join(thread2,NULL);
    return 0;

}

compile with -lpthread

http://en.wikipedia.org/wiki/POSIX_Threads

UICollectionView Set number of columns

With Swift 5 and iOS 12.3, you can use one the 4 following implementations in order to set the number of items per row in your UICollectionView while managing insets and size changes (including rotation).


#1. Subclassing UICollectionViewFlowLayout and using UICollectionViewFlowLayout's itemSize property

ColumnFlowLayout.swift:

import UIKit

class ColumnFlowLayout: UICollectionViewFlowLayout {

    let cellsPerRow: Int

    init(cellsPerRow: Int, minimumInteritemSpacing: CGFloat = 0, minimumLineSpacing: CGFloat = 0, sectionInset: UIEdgeInsets = .zero) {
        self.cellsPerRow = cellsPerRow
        super.init()

        self.minimumInteritemSpacing = minimumInteritemSpacing
        self.minimumLineSpacing = minimumLineSpacing
        self.sectionInset = sectionInset
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override func prepare() {
        super.prepare()

        guard let collectionView = collectionView else { return }
        let marginsAndInsets = sectionInset.left + sectionInset.right + collectionView.safeAreaInsets.left + collectionView.safeAreaInsets.right + minimumInteritemSpacing * CGFloat(cellsPerRow - 1)
        let itemWidth = ((collectionView.bounds.size.width - marginsAndInsets) / CGFloat(cellsPerRow)).rounded(.down)
        itemSize = CGSize(width: itemWidth, height: itemWidth)
    }

    override func invalidationContext(forBoundsChange newBounds: CGRect) -> UICollectionViewLayoutInvalidationContext {
        let context = super.invalidationContext(forBoundsChange: newBounds) as! UICollectionViewFlowLayoutInvalidationContext
        context.invalidateFlowLayoutDelegateMetrics = newBounds.size != collectionView?.bounds.size
        return context
    }

}

CollectionViewController.swift:

import UIKit

class CollectionViewController: UICollectionViewController {

    let columnLayout = ColumnFlowLayout(
        cellsPerRow: 5,
        minimumInteritemSpacing: 10,
        minimumLineSpacing: 10,
        sectionInset: UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)
    )

    override func viewDidLoad() {
        super.viewDidLoad()

        collectionView?.collectionViewLayout = columnLayout
        collectionView?.contentInsetAdjustmentBehavior = .always
        collectionView?.register(UICollectionViewCell.self, forCellWithReuseIdentifier: "Cell")
    }

    override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 59
    }

    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath)
        cell.backgroundColor = UIColor.orange
        return cell
    }

}

enter image description here


#2. Using UICollectionViewFlowLayout's itemSize method

import UIKit

class CollectionViewController: UICollectionViewController {

    let margin: CGFloat = 10
    let cellsPerRow = 5

    override func viewDidLoad() {
        super.viewDidLoad()

        guard let collectionView = collectionView, let flowLayout = collectionViewLayout as? UICollectionViewFlowLayout else { return }

        flowLayout.minimumInteritemSpacing = margin
        flowLayout.minimumLineSpacing = margin
        flowLayout.sectionInset = UIEdgeInsets(top: margin, left: margin, bottom: margin, right: margin)

        collectionView.contentInsetAdjustmentBehavior = .always
        collectionView.register(UICollectionViewCell.self, forCellWithReuseIdentifier: "Cell")
    }

    override func viewWillLayoutSubviews() {
        guard let collectionView = collectionView, let flowLayout = collectionView.collectionViewLayout as? UICollectionViewFlowLayout else { return }
        let marginsAndInsets = flowLayout.sectionInset.left + flowLayout.sectionInset.right + collectionView.safeAreaInsets.left + collectionView.safeAreaInsets.right + flowLayout.minimumInteritemSpacing * CGFloat(cellsPerRow - 1)
        let itemWidth = ((collectionView.bounds.size.width - marginsAndInsets) / CGFloat(cellsPerRow)).rounded(.down)
        flowLayout.itemSize =  CGSize(width: itemWidth, height: itemWidth)
    }

    override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 59
    }

    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath)
        cell.backgroundColor = UIColor.orange
        return cell
    }

    override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        collectionView?.collectionViewLayout.invalidateLayout()
        super.viewWillTransition(to: size, with: coordinator)
    }

}

#3. Using UICollectionViewDelegateFlowLayout's collectionView(_:layout:sizeForItemAt:) method

import UIKit

class CollectionViewController: UICollectionViewController, UICollectionViewDelegateFlowLayout {

    let inset: CGFloat = 10
    let minimumLineSpacing: CGFloat = 10
    let minimumInteritemSpacing: CGFloat = 10
    let cellsPerRow = 5

    override func viewDidLoad() {
        super.viewDidLoad()

        collectionView?.contentInsetAdjustmentBehavior = .always
        collectionView?.register(UICollectionViewCell.self, forCellWithReuseIdentifier: "Cell")
    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
        return UIEdgeInsets(top: inset, left: inset, bottom: inset, right: inset)
    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
        return minimumLineSpacing
    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
        return minimumInteritemSpacing
    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        let marginsAndInsets = inset * 2 + collectionView.safeAreaInsets.left + collectionView.safeAreaInsets.right + minimumInteritemSpacing * CGFloat(cellsPerRow - 1)
        let itemWidth = ((collectionView.bounds.size.width - marginsAndInsets) / CGFloat(cellsPerRow)).rounded(.down)
        return CGSize(width: itemWidth, height: itemWidth)
    }

    override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 59
    }

    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath)
        cell.backgroundColor = UIColor.orange
        return cell
    }

    override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        collectionView?.collectionViewLayout.invalidateLayout()
        super.viewWillTransition(to: size, with: coordinator)
    }

}

#4. Subclassing UICollectionViewFlowLayout and using UICollectionViewFlowLayout's estimatedItemSize property

CollectionViewController.swift:

import UIKit

class CollectionViewController: UICollectionViewController {

    let items = [
        "Lorem ipsum dolor sit amet, consectetur adipiscing elit.",
        "Lorem ipsum dolor sit amet, consectetur.",
        "Lorem ipsum dolor sit amet.",
        "Lorem ipsum dolor sit amet, consectetur.",
        "Lorem ipsum dolor sit amet, consectetur adipiscing.",
        "Lorem ipsum.",
        "Lorem ipsum dolor sit amet.",
        "Lorem ipsum dolor sit.",
        "Lorem ipsum dolor sit amet, consectetur adipiscing.",
        "Lorem ipsum dolor sit amet, consectetur adipiscing elit.",
        "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor.",
        "Lorem ipsum dolor sit amet, consectetur."
    ]

    let columnLayout = FlowLayout(
        cellsPerRow: 3,
        minimumInteritemSpacing: 10,
        minimumLineSpacing: 10,
        sectionInset: UIEdgeInsets(top: 10, left: 10, bottom: 10, right: 10)
    )

    override func viewDidLoad() {
        super.viewDidLoad()

        collectionView?.collectionViewLayout = columnLayout
        collectionView?.contentInsetAdjustmentBehavior = .always
        collectionView?.register(Cell.self, forCellWithReuseIdentifier: "Cell")
    }

    override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return items.count
    }

    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) as! Cell
        cell.label.text = items[indexPath.row]
        return cell
    }

    override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        collectionView?.collectionViewLayout.invalidateLayout()
        super.viewWillTransition(to: size, with: coordinator)
    }

}

FlowLayout.swift:

import UIKit

class FlowLayout: UICollectionViewFlowLayout {

    let cellsPerRow: Int

    required init(cellsPerRow: Int = 1, minimumInteritemSpacing: CGFloat = 0, minimumLineSpacing: CGFloat = 0, sectionInset: UIEdgeInsets = .zero) {
        self.cellsPerRow = cellsPerRow

        super.init()

        self.minimumInteritemSpacing = minimumInteritemSpacing
        self.minimumLineSpacing = minimumLineSpacing
        self.sectionInset = sectionInset
        estimatedItemSize = UICollectionViewFlowLayout.automaticSize
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override func layoutAttributesForItem(at indexPath: IndexPath) -> UICollectionViewLayoutAttributes? {
        guard let layoutAttributes = super.layoutAttributesForItem(at: indexPath) else { return nil }
        guard let collectionView = collectionView else { return layoutAttributes }

        let marginsAndInsets = collectionView.safeAreaInsets.left + collectionView.safeAreaInsets.right + sectionInset.left + sectionInset.right + minimumInteritemSpacing * CGFloat(cellsPerRow - 1)
        layoutAttributes.bounds.size.width = ((collectionView.bounds.width - marginsAndInsets) / CGFloat(cellsPerRow)).rounded(.down)

        return layoutAttributes
    }

    override func layoutAttributesForElements(in rect: CGRect) -> [UICollectionViewLayoutAttributes]? {
        let superLayoutAttributes = super.layoutAttributesForElements(in: rect)!.map { $0.copy() as! UICollectionViewLayoutAttributes }
        guard scrollDirection == .vertical else { return superLayoutAttributes }

        let layoutAttributes = superLayoutAttributes.compactMap { layoutAttribute in
            return layoutAttribute.representedElementCategory == .cell ? layoutAttributesForItem(at: layoutAttribute.indexPath) : layoutAttribute
        }

        // (optional) Uncomment to top align cells that are on the same line
        /*
        let cellAttributes = layoutAttributes.filter({ $0.representedElementCategory == .cell })
        for (_, attributes) in Dictionary(grouping: cellAttributes, by: { ($0.center.y / 10).rounded(.up) * 10 }) {
            guard let max = attributes.max(by: { $0.size.height < $1.size.height }) else { continue }
            for attribute in attributes where attribute.size.height != max.size.height {
                attribute.frame.origin.y = max.frame.origin.y
            }
        }
         */

        // (optional) Uncomment to bottom align cells that are on the same line
        /*
        let cellAttributes = layoutAttributes.filter({ $0.representedElementCategory == .cell })
        for (_, attributes) in Dictionary(grouping: cellAttributes, by: { ($0.center.y / 10).rounded(.up) * 10 }) {
            guard let max = attributes.max(by: { $0.size.height < $1.size.height }) else { continue }
            for attribute in attributes where attribute.size.height != max.size.height {
                attribute.frame.origin.y += max.frame.maxY - attribute.frame.maxY
            }
        }
         */

        return layoutAttributes
    }

}

Cell.swift:

import UIKit

class Cell: UICollectionViewCell {

    let label = UILabel()

    override init(frame: CGRect) {
        super.init(frame: frame)

        label.numberOfLines = 0
        backgroundColor = .orange
        contentView.addSubview(label)

        label.translatesAutoresizingMaskIntoConstraints = false
        label.topAnchor.constraint(equalTo: contentView.layoutMarginsGuide.topAnchor).isActive = true
        label.leadingAnchor.constraint(equalTo: contentView.layoutMarginsGuide.leadingAnchor).isActive = true
        label.trailingAnchor.constraint(equalTo: contentView.layoutMarginsGuide.trailingAnchor).isActive = true
        label.bottomAnchor.constraint(equalTo: contentView.layoutMarginsGuide.bottomAnchor).isActive = true
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override func preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes {
        layoutIfNeeded()
        label.preferredMaxLayoutWidth = label.bounds.size.width
        layoutAttributes.bounds.size.height = contentView.systemLayoutSizeFitting(UIView.layoutFittingCompressedSize).height
        return layoutAttributes
    }

    // Alternative implementation
    /*
    override func preferredLayoutAttributesFitting(_ layoutAttributes: UICollectionViewLayoutAttributes) -> UICollectionViewLayoutAttributes {
        label.preferredMaxLayoutWidth = layoutAttributes.size.width - contentView.layoutMargins.left - contentView.layoutMargins.right
        layoutAttributes.bounds.size.height = contentView.systemLayoutSizeFitting(UIView.layoutFittingCompressedSize).height
        return layoutAttributes
    }
    */

}

enter image description here

How to serve an image using nodejs

You should use the express framework.

npm install express

and then

var express = require('express');
var app = express();
app.use(express.static(__dirname + '/public'));
app.listen(8080);

and then the URL localhost:8080/images/logo.gif should work.

Hide div element when screen size is smaller than a specific size

The easiest approach I know of is using onresize() func:

   window.onresize = function(event) {
        ...
    }

Here is a fiddle for it

Get drop down value

If your dropdown is something like this:

<select id="thedropdown">
  <option value="1">one</option>
  <option value="2">two</option>
</select>

Then you would use something like:

var a = document.getElementById("thedropdown");
alert(a.options[a.selectedIndex].value);

But a library like jQuery simplifies things:

alert($('#thedropdown').val());

Calculating powers of integers

import java.util.*;

public class Power {

    public static void main(String args[])
    {
        Scanner sc=new Scanner(System.in);
        int num = 0;
        int pow = 0;
        int power = 0;

        System.out.print("Enter number: ");
        num = sc.nextInt();

        System.out.print("Enter power: ");
        pow = sc.nextInt();

        System.out.print(power(num,pow));
    }

    public static int power(int a, int b)
    {
        int power = 1;

        for(int c = 0; c < b; c++)
            power *= a;

        return power;
    }

}

UIScrollView scroll to bottom programmatically

valdyr, hope this will help you:

CGPoint bottomOffset = CGPointMake(0, [textView contentSize].height - textView.frame.size.height);

if (bottomOffset.y > 0)
 [textView setContentOffset: bottomOffset animated: YES];

Changing image sizes proportionally using CSS?

Put it as a background on your holder e.g.

<div style="background:url(path/to/image/myimage.jpg) center center; width:120px; height:120px;">
&nbsp;
</div>

This will center your image inside a 120x120 div chopping off any excess of the image

PHP how to get value from array if key is in a variable

As others stated, it's likely failing because the requested key doesn't exist in the array. I have a helper function here that takes the array, the suspected key, as well as a default return in the event the key does not exist.

    protected function _getArrayValue($array, $key, $default = null)
    {
        if (isset($array[$key])) return $array[$key];
        return $default;
    }

hope it helps.

How to get text and a variable in a messagebox

As has been suggested, using the string.format method is nice and simple and very readable.

In vb.net the " + " is used for addition and the " & " is used for string concatenation.

In your example:

MsgBox("Variable = " + variable)

becomes:

MsgBox("Variable = " & variable)

I may have been a bit quick answering this as it appears these operators can both be used for concatenation, but recommended use is the "&", source http://msdn.microsoft.com/en-us/library/te2585xw(v=VS.100).aspx

maybe call

variable.ToString()

update:

Use string interpolation (vs2015 onwards I believe):

MsgBox($"Variable = {variable}")

What is the difference between active and passive FTP?

Active and passive are the two modes that FTP can run in.

For background, FTP actually uses two channels between client and server, the command and data channels, which are actually separate TCP connections.

The command channel is for commands and responses while the data channel is for actually transferring files.

This separation of command information and data into separate channels a nifty way of being able to send commands to the server without having to wait for the current data transfer to finish. As per the RFC, this is only mandated for a subset of commands, such as quitting, aborting the current transfer, and getting the status.


In active mode, the client establishes the command channel but the server is responsible for establishing the data channel. This can actually be a problem if, for example, the client machine is protected by firewalls and will not allow unauthorised session requests from external parties.

In passive mode, the client establishes both channels. We already know it establishes the command channel in active mode and it does the same here.

However, it then requests the server (on the command channel) to start listening on a port (at the servers discretion) rather than trying to establish a connection back to the client.

As part of this, the server also returns to the client the port number it has selected to listen on, so that the client knows how to connect to it.

Once the client knows that, it can then successfully create the data channel and continue.

More details are available in the RFC: https://www.ietf.org/rfc/rfc959.txt

Prevent WebView from displaying "web page not available"

try this shouldOverrideUrlLoading , before redirect to another url check for internet conncetion based on that page should be loaded or not.

Spring AMQP + RabbitMQ 3.3.5 ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN

The error

ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN. For details see the broker logfile.

can occur if the credentials that your application is trying to use to connect to RabbitMQ are incorrect or missing.

I had this happen when the RabbitMQ credentials stored in my ASP.NET application's web.config file had a value of "" for the password instead of the actual password string value.

Moving from JDK 1.7 to JDK 1.8 on Ubuntu

Just use these command lines:

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java8-installer

If needed, you can also follow this Ubuntu tutorial.

mysql data directory location

As suggested, I edited this message to place a proper answer.

The 'physical' location of the mysql databases are under /usr/local/mysql

the mysql is a symlink to the current active mysql installation, in my case the exact folder is mysql-5.6.10-osx10.7-x86_64.

Inside that folder you'll see another data folder, inside it are RESTRICTED folders with your databases.

You can't actually see the size of your databases (that was my issue) from the Finder because the folder are protected, you can though see from the terminal with sudo du -sh /usr/local/mysql/data/{your-database-name} and like this you'll get a nice formatted output with the size.

In those folder you have different files with all the folders present in your database, so it's safer to check the db's folder to get a size.

That's it. Enjoy!

C# cannot convert method to non delegate type

Because getTitle is not a string, it returns a reference or delegate to a method (if you like), if you don't explicitly call the method.

Call your method this way:

string t= obj.getTitle() ; //obj.getTitle()  says return the title string object

However, this would work:

Func<string> method = obj.getTitle; // this compiles to a delegate and points to the method

string s = method();//call the delegate or using this syntax `method.Invoke();`

How to change context root of a dynamic web project in Eclipse?

In Glassfish you must also change the file WEB-INF/glassfish-web.xml

<glassfish-web-app>
    <context-root>/myapp</context-root>
</glassfish-web-app>

So when you click in "Run as> Run on server" it will open correctly.

Table-level backup

If you are looking to be able to restore a table after someone has mistakenly deleted rows from it you could maybe have a look at database snapshots. You could restore the table quite easily (or a subset of the rows) from the snapshot. See http://msdn.microsoft.com/en-us/library/ms175158.aspx

Is 'bool' a basic datatype in C++?

yes, it was introduced in 1993.

for further reference: Boolean Datatype

How can I use nohup to run process as a background process in linux?

In general, I use nohup CMD & to run a nohup background process. However, when the command is in a form that nohup won't accept then I run it through bash -c "...".

For example:

nohup bash -c "(time ./script arg1 arg2 > script.out) &> time_n_err.out" &

stdout from the script gets written to script.out, while stderr and the output of time goes into time_n_err.out.

So, in your case:

nohup bash -c "(time bash executeScript 1 input fileOutput > scrOutput) &> timeUse.txt" &

PowerShell : retrieve JSON object by field value

In regards to PowerShell 5.1 (this is so much easier in PowerShell 7)...

Operating off the assumption that we have a file named jsonConfigFile.json with the following content from your post:

{
    "Stuffs": [
        {
            "Name": "Darts",
            "Type": "Fun Stuff"
        },
        {
            "Name": "Clean Toilet",
            "Type": "Boring Stuff"
        }
    ]
}

This will create an ordered hashtable from a JSON file to help make retrieval easier:

$json = [ordered]@{}

(Get-Content "jsonConfigFile.json" -Raw | ConvertFrom-Json).PSObject.Properties |
    ForEach-Object { $json[$_.Name] = $_.Value }

$json.Stuffs will list a nice hashtable, but it gets a little more complicated from here. Say you want the Type key's value associated with the Clean Toilet key, you would retrieve it like this:

$json.Stuffs.Where({$_.Name -eq "Clean Toilet"}).Type

It's a pain in the ass, but if your goal is to use JSON on a barebones Windows 10 installation, this is the best way to do it as far as I've found.

Allow 2 decimal places in <input type="number">

For currency, I'd suggest:

<div><label>Amount $
    <input type="number" placeholder="0.00" required name="price" min="0" value="0" step="0.01" title="Currency" pattern="^\d+(?:\.\d{1,2})?$" onblur="
this.parentNode.parentNode.style.backgroundColor=/^\d+(?:\.\d{1,2})?$/.test(this.value)?'inherit':'red'
"></label></div>

See http://jsfiddle.net/vx3axsk5/1/

The HTML5 properties "step", "min" and "pattern" will be validated when the form is submit, not onblur. You don't need the step if you have a pattern and you don't need a pattern if you have a step. So you could revert back to step="any" with my code since the pattern will validate it anyways.

If you'd like to validate onblur, I believe giving the user a visual cue is also helpful like coloring the background red. If the user's browser doesn't support type="number" it will fallback to type="text". If the user's browser doesn't support the HTML5 pattern validation, my JavaScript snippet doesn't prevent the form from submitting, but it gives a visual cue. So for people with poor HTML5 support, and people trying to hack into the database with JavaScript disabled or forging HTTP Requests, you need to validate on the server again anyways. The point with validation on the front-end is for a better user experience. So as long as most of your users have a good experience, it's fine to rely on HTML5 features provided the code will still works and you can validate on the back-end.

ResourceDictionary in a separate assembly

I'm working with .NET 4.5 and couldn't get this working... I was using WPF Custom Control Library. This worked for me in the end...

<ResourceDictionary Source="/MyAssembly;component/mytheme.xaml" />

source: http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/11a42336-8d87-4656-91a3-275413d3cc19

How to change the style of alert box?

I use sweetalert2 library. It's really simple, a lot of customization, modern, animated windows, eye-catching, and also nice design.

Swal.fire({
  icon: 'error',
  title: 'Oops...',
  text: 'Something went wrong!',
  footer: '<a href>Why do I have this issue?</a>'
})

Check this link

Is it possible to set ENV variables for rails development environment in my code?

The way I am trying to do this in my question actually works!

# environment/development.rb

ENV['admin_password'] = "secret" 

I just had to restart the server. I thought running reload! in rails console would be enough but I also had to restart the web server.

I am picking my own answer because I feel this is a better place to put and set the ENV variables

HTML anchor link - href and onclick both?

Just return true instead?

The return value from the onClick code is what determines whether the link's inherent clicked action is processed or not - returning false means that it isn't processed, but if you return true then the browser will proceed to process it after your function returns and go to the proper anchor.

How to show the "Are you sure you want to navigate away from this page?" when changes committed?

When the user starts making changes to the form, a boolean flag will be set. If the user then tries to navigate away from the page, you check that flag in the window.onunload event. If the flag is set, you show the message by returning it as a string. Returning the message as a string will popup a confirmation dialog containing your message.

If you are using ajax to commit the changes, you can set the flag to false after the changes have been committed (i.e. in the ajax success event).

Clang vs GCC - which produces faster binaries?

Phoronix did some benchmarks about this, but it is about a snapshot version of Clang/LLVM from a few months back. The results being that things were more-or-less a push; neither GCC nor Clang is definitively better in all cases.

Since you'd use the latest Clang, it's maybe a little less relevant. Then again, GCC 4.6 is slated to have some major optimizations for Core 2 and i7, apparently.

I figure Clang's faster compilation speed will be nicer for original developers, and then when you push the code out into the world, Linux distro/BSD/etc. end-users will use GCC for the faster binaries.

Replacing H1 text with a logo image: best method for SEO and accessibility?

I don't know but this is the format have used...

<h1>
    <span id="site-logo" title="xxx" href="#" target="_self">
        <img src="http://www.xxx.com/images/xxx.png" alt="xxx" width="xxx" height="xxx" />
        <a style="display:none">
            <strong>xxx</strong>
        </a>
    </span>
</h1>

Simple and it has not done my site any harm as far as I can see. You could css it but I don't see it loading any faster.

How to display binary data as image - extjs 4

In front-end JavaScript/HTML, you can load a binary file as an image, you do not have to convert to base64:

<img src="http://engci.nabisco.com/artifactory/repo/folder/my-image">

my-image is a binary image file. This will load just fine.

Get value when selected ng-option changes

Best practise is to create an object (always use a . in ng-model)

In your controller:

var myObj: {
     ngModelValue: null
};

and in your template:

<select 
    ng-model="myObj.ngModelValue" 
    ng-options="o.id as o.name for o in options">
</select>

Now you can just watch

myObj.ngModelValue

or you can use the ng-change directive like so:

<select 
    ng-model="myObj.ngModelValue" 
    ng-options="o.id as o.name for o in options"
    ng-change="myChangeCallback()">
</select>

The egghead.io video "The Dot" has a really good overview, as does this very popular stack overflow question: What are the nuances of scope prototypal / prototypical inheritance in AngularJS?

How to convert InputStream to FileInputStream

Use ClassLoader#getResource() instead if its URI represents a valid local disk file system path.

URL resource = classLoader.getResource("resource.ext");
File file = new File(resource.toURI());
FileInputStream input = new FileInputStream(file);
// ...

If it doesn't (e.g. JAR), then your best bet is to copy it into a temporary file.

Path temp = Files.createTempFile("resource-", ".ext");
Files.copy(classLoader.getResourceAsStream("resource.ext"), temp, StandardCopyOption.REPLACE_EXISTING);
FileInputStream input = new FileInputStream(temp.toFile());
// ...

That said, I really don't see any benefit of doing so, or it must be required by a poor helper class/method which requires FileInputStream instead of InputStream. If you can, just fix the API to ask for an InputStream instead. If it's a 3rd party one, by all means report it as a bug. I'd in this specific case also put question marks around the remainder of that API.

Push eclipse project to GitHub with EGit

The key lies in when you create the project in eclipse.

First step, you create the Java project in eclipse. Right click on the project and choose Team > Share>Git.

In the Configure Git Repository dialog, ensure that you select the option to create the Repository in the parent folder of the project.. enter image description here Then you can push to github.

N.B: Eclipse will give you a warning about putting git repositories in your workspace. So when you create your project, set your project directory outside the default workspace.

RabbitMQ / AMQP: single queue, multiple consumers for same message?

If you happen to be using the amqplib library as I am, they have a handy example of an implementation of the Publish/Subscribe RabbitMQ tutorial which you might find handy.

Difference between Spring MVC and Struts MVC

Spring MVC is deeply integreated in Spring, Struts MVC is not.

Pause Console in C++ program

Late response, but I think it will help others.

Part of imitating system("pause") is imitating what it asks the user to do: "Press any key to continue . . . " So, we need something that does not wait for simply a return as std::cin.get() would do. Even getch() has its problems when used twice (the second time call has been noticed to skip pausing generally if it's immediately paused again afterwards on the same key press). I think it has to do with the input buffer. System("pause") is usually not recommended, but we still need something to imitate what users might already expect. I prefer getch() because it doesn't echo to the screen, and it works dynamically.

The solution is to do the following using a do-while loop:

void Console::pause()
{ 
    int ch = 0;

    std::cout << "\nPress any key to continue . . . ";

    do {
        ch = getch();
    } while (ch != 0);

    std::cout << std::endl;
} 

Now it waits for the user to press any key. If it's used twice, it waits for the user again instead of skipping.

Fatal error: Class 'SoapClient' not found

On Centos 7.8 and PHP 7.3

yum install php-soap
service httpd restart

Improving bulk insert performance in Entity framework

Currently there is no better way, however there may be a marginal improvement by moving SaveChanges inside for loop for probably 10 items.

int i = 0;

foreach (Employees item in sequence)
{
   t = new Employees ();
   t.Text = item.Text;
   dataContext.Employees.AddObject(t);   

   // this will add max 10 items together
   if((i % 10) == 0){
       dataContext.SaveChanges();
       // show some progress to user based on
       // value of i
   }
   i++;
}
dataContext.SaveChanges();

You can adjust 10 to be closer to better performance. It will not greatly improve speed but it will allow you to show some progress to user and make it more user friendly.

How do I insert non breaking space character &nbsp; in a JSF page?

If your using the RichFaces library you can also use the tag rich:spacer which will add an "invisible" image with a given length and height. Usually much easier and prettier than to add tons of nbsp;.

Where you want your space to show you simply add:

<rich:spacer height="1" width="2" />

Can Android Studio be used to run standard Java projects?

I found a somewhat hacky, annoying and not-completely-sure-it-always-works solution to this. I wanted to share in case someone else finds it useful.

In Android Studio, you can right-click a class with a main method and select "Run .main()". This will create a new Run configuration for YourClass, although it won't quite work: it will be missing some classpath entries.

In order to fix the missing classpath entries, go into the Project Structure and manually add the output folder location for your module and any other module dependencies that you need, like so:

  • File -> Project Structure ...
  • Select "Modules" in the Project Settings panel on the left-column panel
  • Select your module on the list of modules in the middle-column panel
  • Select the "Dependencies" tab on the right-column panel

And then for the module where you have your Java application as well as for each of the module dependencies you need: - Click "+" -> "Jars or directories" on the far right of the right-column panel - Navigate to the output folder of the module (e.g.: my_module/build/classes/main/java) and click "OK" - On the new entry to the Dependencies list, on the far right, change the select box from "Compile" to "Runtime"

After this, you should be able to execute the Run configuration you just created to run the simple Java application.

One thing to note is that, for my particular [quite involved] Android Studio project set-up, I have to manually build the project with gradle, from outside Android Studio in order to get my simple Java Application classes to build, before I run the application - I think this is because the Run configuration of type "Application" is not triggering the corresponding Gradle build.

Finally, this was done on Android Studio 0.4.0.

I hope others find it useful. I also hope Google comes around to supporting this functionality soon.

Android translate animation - permanently move View to new position using AnimationListener

This is what worked for me perfectly:-

// slide the view from its current position to below itself
public void slideUp(final View view, final View llDomestic){

    ObjectAnimator animation = ObjectAnimator.ofFloat(view, "translationY",0f);
    animation.setDuration(100);
    llDomestic.setVisibility(View.GONE);
    animation.start();

}

// slide the view from below itself to the current position
public void slideDown(View view,View llDomestic){
    llDomestic.setVisibility(View.VISIBLE);
    ObjectAnimator animation = ObjectAnimator.ofFloat(view, "translationY",   0f);
    animation.setDuration(100);
    animation.start();
}

llDomestic : The view which you want to hide. view: The view which you want to move down or up.

How to parse/format dates with LocalDateTime? (Java 8)

Parsing a string with date and time into a particular point in time (Java calls it an "Instant") is quite complicated. Java has been tackling this in several iterations. The latest one, java.time and java.time.chrono, covers almost all needs (except Time Dilation :) ).

However, that complexity brings a lot of confusion.

The key to understand date parsing is:

Why does Java have so many ways to parse a date

  1. There are several systems to measure a time. For instance, the historical Japanese calendars were derived from the time ranges of the reign of the respective emperor or dynasty. Then there is e.g. UNIX timestamp. Fortunately, the whole (business) world managed to use the same.
  2. Historically, the systems were being switched from/to, for various reasons. E.g. from Julian calendar to Gregorian calendar in 1582. So 'western' dates before that need to be treated differently.
  3. And of course the change did not happen at once. Because the calendar came from the headquarteds of some religion and other parts of Europe believed in other dieties, for instance Germany did not switch until the year 1700.

...and why is the LocalDateTime, ZonedDateTime et al. so complicated

  1. There are time zones. A time zone is basically a "stripe"*[1] of the Earth's surface whose authorities follow the same rules of when does it have which time offset. This includes summer time rules.
    The time zones change over time for various areas, mostly based on who conquers whom. And one time zone's rules change over time as well.

  2. There are time offsets. That is not the same as time zones, because a time zone may be e.g. "Prague", but that has summer time offset and winter time offset.
    If you get a timestamp with a time zone, the offset may vary, depending on what part of the year it is in. During the leap hour, the timestamp may mean 2 different times, so without additional information, it can't be reliably converted.
    Note: By timestamp I mean "a string that contains a date and/or time, optionally with a time zone and/or time offset."

  3. Several time zones may share the same time offset for certain periods. For instance, GMT/UTC time zone is the same as "London" time zone when the summer time offset is not in effect.

To make it a bit more complicated (but that's not too important for your use case) :

  1. The scientists observe Earth's dynamic, which changes over time; based on that, they add seconds at the end of individual years. (So 2040-12-31 24:00:00 may be a valid date-time.) This needs regular updates of the metadata that systems use to have the date conversions right. E.g. on Linux, you get regular updates to the Java packages including these new data.
  2. The updates do not always keep the previous behavior for both historical and future timestamps. So it may happen that parsing of the two timestamps around some time zone's change comparing them may give different results when running on different versions of the software. That also applies to comparing between the affected time zone and other time zone.

    Should this cause a bug in your software, consider using some timestamp that does not have such complicated rules, like UNIX timestamp.

  3. Because of 7, for the future dates, we can't convert dates exactly with certainty. So, for instance, current parsing of 8524-02-17 12:00:00 may be off a couple of seconds from the future parsing.

JDK's APIs for this evolved with the contemporary needs

  • The early Java releases had just java.util.Date which had a bit naive approach, assuming that there's just the year, month, day, and time. This quickly did not suffice.
  • Also, the needs of the databases were different, so quite early, java.sql.Date was introduced, with it's own limitations.
  • Because neither covered different calendars and time zones well, the Calendar API was introduced.
  • This still did not cover the complexity of the time zones. And yet, the mix of the above APIs was really a pain to work with. So as Java developers started working on global web applications, libraries that targeted most use cases, like JodaTime, got quickly popular. JodaTime was the de-facto standard for about a decade.
  • But the JDK did not integrate with JodaTime, so working with it was a bit cumbersome. So, after a very long discussion on how to approach the matter, JSR-310 was created mainly based on JodaTime.

How to deal with it in Java's java.time

Determine what type to parse a timestamp to

When you are consuming a timestamp string, you need to know what information it contains. This is the crucial point. If you don't get this right, you end up with a cryptic exceptions like "Can't create Instant" or "Zone offset missing" or "unknown zone id" etc.

Does it contain the date and the time?

  1. Does it have a time offset?
    A time offset is the +hh:mm part. Sometimes, +00:00 may be substituted with Z as 'Zulu time', UTC as Universal Time Coordinated, or GMT as Greenwich Mean Time. These also set the time zone.
    For these timestamps, you use OffsetDateTime.

  2. Does it have a time zone?
    For these timestamps, you use ZonedDateTime.
    Zone is specified either by

    • name ("Prague", "Pacific Standard Time", "PST"), or
    • "zone ID" ("America/Los_Angeles", "Europe/London"), represented by java.time.ZoneId.

    The list of time zones is compiled by a "TZ database", backed by ICAAN.

    According to ZoneId's javadoc, The zone id's can also somehow be specified as Z and offset. I'm not sure how this maps to real zones. If the timestamp, which only has a TZ, falls into a leap hour of time offset change, then it is ambiguous, and the interpretation is subject of ResolverStyle, see below.

  3. If it has neither, then the missing context is assumed or neglected. And the consumer has to decide. So it needs to be parsed as LocalDateTime and converted to OffsetDateTime by adding the missing info:

    • You can assume that it is a UTC time. Add the UTC offset of 0 hours.
    • You can assume that it is a time of the place where the conversion is happening. Convert it by adding the system's time zone.
    • You can neglect and just use it as is. That is useful e.g. to compare or substract two times (see Duration), or when you don't know and it doesn't really matter (e.g. local bus schedule).

Partial time information

  • Based on what the timestamp contains, you can take LocalDate, LocalTime, OffsetTime, MonthDay, Year, or YearMonth out of it.

If you have the full information, you can get a java.time.Instant. This is also internally used to convert between OffsetDateTime and ZonedDateTime.

Figure out how to parse it

There is an extensive documentation on DateTimeFormatter which can both parse a timestamp string and format to string.

The pre-created DateTimeFormatters should cover moreless all standard timestamp formats. For instance, ISO_INSTANT can parse 2011-12-03T10:15:30.123457Z.

If you have some special format, then you can create your own DateTimeFormatter (which is also a parser).

private static final DateTimeFormatter TIMESTAMP_PARSER = new DateTimeFormatterBuilder()
   .parseCaseInsensitive()
   .append(DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SX"))
   .toFormatter();

I recommend to look at the source code of DateTimeFormatter and get inspired on how to build one using DateTimeFormatterBuilder. While you're there, also have a look at ResolverStyle which controls whether the parser is LENIENT, SMART or STRICT for the formats and ambiguous information.

TemporalAccessor

Now, the frequent mistake is to go into the complexity of TemporalAccessor. This comes from how the developers were used to work with SimpleDateFormatter.parse(String). Right, DateTimeFormatter.parse("...") gives you TemporalAccessor.

// No need for this!
TemporalAccessor ta = TIMESTAMP_PARSER.parse("2011-... etc");

But, equiped with the knowledge from the previous section, you can conveniently parse into the type you need:

OffsetDateTime myTimestamp = OffsetDateTime.parse("2011-12-03T10:15:30.123457Z", TIMESTAMP_PARSER);

You do not actually need to the DateTimeFormatter either. The types you want to parse have the parse(String) methods.

OffsetDateTime myTimestamp = OffsetDateTime.parse("2011-12-03T10:15:30.123457Z");

Regarding TemporalAccessor, you can use it if you have a vague idea of what information there is in the string, and want to decide at runtime.

I hope I shed some light of understanding onto your soul :)

Note: There's a backport of java.time to Java 6 and 7: ThreeTen-Backport. For Android it has ThreeTenABP.

[1] Not just that they are not stripes, but there also some weird extremes. For instance, some neighboring pacific islands have +14:00 and -11:00 time zones. That means, that while on one island, there is 1st May 3 PM, on another island not so far, it is still 30 April 12 PM (if I counted correctly :) )

How to use GROUP BY to concatenate strings in MySQL?

SELECT id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;

:- In MySQL, you can get the concatenated values of expression combinations . To eliminate duplicate values, use the DISTINCT clause. To sort values in the result, use the ORDER BY clause. To sort in reverse order, add the DESC (descending) keyword to the name of the column you are sorting by in the ORDER BY clause. The default is ascending order; this may be specified explicitly using the ASC keyword. The default separator between values in a group is comma (“,”). To specify a separator explicitly, use SEPARATOR followed by the string literal value that should be inserted between group values. To eliminate the separator altogether, specify SEPARATOR ''.

GROUP_CONCAT([DISTINCT] expr [,expr ...]
             [ORDER BY {unsigned_integer | col_name | expr}
                 [ASC | DESC] [,col_name ...]]
             [SEPARATOR str_val])

OR

mysql> SELECT student_name,
    ->     GROUP_CONCAT(DISTINCT test_score
    ->               ORDER BY test_score DESC SEPARATOR ' ')
    ->     FROM student
    ->     GROUP BY student_name;

javascript cell number validation

<script type="text/javascript">
    function MobileNoValidation()
    {
       var phno=/^\d{10}$/
       if(textMobileNo.value=="")
       {
        alert("Mobile No Should Not Be Empty");
       }
       else if(!textMobileNo.value.match(phno))
       {
        alert("Mobile no must be ten digit");
       }
       else
       {
        alert("valid Mobile No");
       }
    }
</script>

Change image size with JavaScript

You can change the actual width/height attributes like this:

var theImg = document.getElementById('theImgId');
theImg.height = 150;
theImg.width = 150;

How do I make background-size work in IE?

you can use this file (https://github.com/louisremi/background-size-polyfill “background-size polyfill”) for IE8 that is really simple to use:

.selector {
background-size: cover;
-ms-behavior: url(/backgroundsize.min.htc);
}

How do I group Windows Form radio buttons?

I like the concept of grouping RadioButtons in WPF. There is a property GroupName that specifies which RadioButton controls are mutually exclusive (http://msdn.microsoft.com/de-de/library/system.windows.controls.radiobutton.aspx).

So I wrote a derived class for WinForms that supports this feature:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;
using System.Windows.Forms.VisualStyles;
using System.Drawing;
using System.ComponentModel;

namespace Use.your.own
{
    public class AdvancedRadioButton : CheckBox
    {
        public enum Level { Parent, Form };

        [Category("AdvancedRadioButton"),
        Description("Gets or sets the level that specifies which RadioButton controls are affected."),
        DefaultValue(Level.Parent)]
        public Level GroupNameLevel { get; set; }

        [Category("AdvancedRadioButton"),
        Description("Gets or sets the name that specifies which RadioButton controls are mutually exclusive.")]
        public string GroupName { get; set; }

        protected override void OnCheckedChanged(EventArgs e)
        {
            base.OnCheckedChanged(e);

            if (Checked)
            {
                var arbControls = (dynamic)null;
                switch (GroupNameLevel)
                {
                    case Level.Parent:
                        if (this.Parent != null)
                            arbControls = GetAll(this.Parent, typeof(AdvancedRadioButton));
                        break;
                    case Level.Form:
                        Form form = this.FindForm();
                        if (form != null)
                            arbControls = GetAll(this.FindForm(), typeof(AdvancedRadioButton));
                        break;
                }
                if (arbControls != null)
                    foreach (Control control in arbControls)
                        if (control != this &&
                            (control as AdvancedRadioButton).GroupName == this.GroupName)
                            (control as AdvancedRadioButton).Checked = false;
            }
        }

        protected override void OnClick(EventArgs e)
        {
            if (!Checked)
                base.OnClick(e);
        }

        protected override void OnPaint(PaintEventArgs pevent)
        {
            CheckBoxRenderer.DrawParentBackground(pevent.Graphics, pevent.ClipRectangle, this);

            RadioButtonState radioButtonState;
            if (Checked)
            {
                radioButtonState = RadioButtonState.CheckedNormal;
                if (Focused)
                    radioButtonState = RadioButtonState.CheckedHot;
                if (!Enabled)
                    radioButtonState = RadioButtonState.CheckedDisabled;
            }
            else
            {
                radioButtonState = RadioButtonState.UncheckedNormal;
                if (Focused)
                    radioButtonState = RadioButtonState.UncheckedHot;
                if (!Enabled)
                    radioButtonState = RadioButtonState.UncheckedDisabled;
            }

            Size glyphSize = RadioButtonRenderer.GetGlyphSize(pevent.Graphics, radioButtonState);
            Rectangle rect = pevent.ClipRectangle;
            rect.Width -= glyphSize.Width;
            rect.Location = new Point(rect.Left + glyphSize.Width, rect.Top);

            RadioButtonRenderer.DrawRadioButton(pevent.Graphics, new System.Drawing.Point(0, rect.Height / 2 - glyphSize.Height / 2), rect, this.Text, this.Font, this.Focused, radioButtonState);
        }

        private IEnumerable<Control> GetAll(Control control, Type type)
        {
            var controls = control.Controls.Cast<Control>();

            return controls.SelectMany(ctrl => GetAll(ctrl, type))
                                      .Concat(controls)
                                      .Where(c => c.GetType() == type);
        }
    }
}

What do <o:p> elements do anyway?

Couldn't find any official documentation (no surprise there) but according to this interesting article, those elements are injected in order to enable Word to convert the HTML back to fully compatible Word document, with everything preserved.

The relevant paragraph:

Microsoft added the special tags to Word's HTML with an eye toward backward compatibility. Microsoft wanted you to be able to save files in HTML complete with all of the tracking, comments, formatting, and other special Word features found in traditional DOC files. If you save a file in HTML and then reload it in Word, theoretically you don't loose anything at all.

This makes lots of sense.

For your specific question.. the o in the <o:p> means "Office namespace" so anything following the o: in a tag means "I'm part of Office namespace" - in case of <o:p> it just means paragraph, the equivalent of the ordinary <p> tag.

I assume that every HTML tag has its Office "equivalent" and they have more.

Storing Images in PostgreSQL

Re jcoby's answer:

bytea being a "normal" column also means the value being read completely into memory when you fetch it. Blobs, in contrast, you can stream into stdout. That helps in reducing the server memory footprint. Especially, when you store 4-6 MPix images.

No problem with backing up blobs. pg_dump provides "-b" option to include the large objects into the backup.

So, I prefer using pg_lo_*, you may guess.

Re Kris Erickson's answer:

I'd say the opposite :). When images are not the only data you store, don't store them on the file system unless you absolutely have to. It's such a benefit to be always sure about your data consistency, and to have the data "in one piece" (the DB). BTW, PostgreSQL is great in preserving consistency.

However, true, reality is often too performance-demanding ;-), and it pushes you to serve the binary files from the file system. But even then I tend to use the DB as the "master" storage for binaries, with all the other relations consistently linked, while providing some file system-based caching mechanism for performance optimization.

Delete duplicate elements from an array

It's easier using Array.filter:

var unique = arr.filter(function(elem, index, self) {
    return index === self.indexOf(elem);
})

Where does forever store console.log output?

This worked for me :

forever -a -o out.log -e err.log app.js

How to set a default row for a query that returns no rows?

How about this:

SELECT DEF.Rate, ACTUAL.Rate, COALESCE(ACTUAL.Rate, DEF.Rate) AS UseThisRate
FROM 
  (SELECT 0) DEF (Rate) -- This is your default rate
LEFT JOIN (
  select rate 
  from d_payment_index
  --WHERE 1=2   -- Uncomment this line to simulate a missing value

  --...HERE IF YOUR ACTUAL WHERE CLAUSE. Removed for testing purposes...
  --where fy = 2007
  -- and payment_year = 2008
  --  and program_id = 18
) ACTUAL (Rate) ON 1=1

Results

Valid Rate Exists

Rate        Rate        UseThisRate
----------- ----------- -----------
0           1           1

Default Rate Used

Rate        Rate        UseThisRate
----------- ----------- -----------
0           NULL        0

Test DDL

CREATE TABLE d_payment_index (rate int NOT NULL)
INSERT INTO d_payment_index VALUES (1)

Copy data from another Workbook through VBA

The best (and easiest) way to copy data from a workbook to another is to use the object model of Excel.

Option Explicit
Sub test()
    Dim wb As Workbook, wb2 As Workbook
    Dim ws As Worksheet
    Dim vFile As Variant

    'Set source workbook
    Set wb = ActiveWorkbook
    'Open the target workbook
    vFile = Application.GetOpenFilename("Excel-files,*.xls", _
        1, "Select One File To Open", , False)
    'if the user didn't select a file, exit sub
    If TypeName(vFile) = "Boolean" Then Exit Sub
    Workbooks.Open vFile
    'Set targetworkbook
    Set wb2 = ActiveWorkbook

    'For instance, copy data from a range in the first workbook to another range in the other workbook
    wb2.Worksheets("Sheet2").Range("C3:D4").Value = wb.Worksheets("Sheet1").Range("A1:B2").Value
End Sub

In Perl, how to remove ^M from a file?

This one liner replaces all the ^M characters:

dos2unix <file-name>

You can call this from inside Perl or directly on your Unix prompt.

How do I mock a service that returns promise in AngularJS Jasmine unit test?

describe('testing a method() on a service', function () {    

    var mock, service

    function init(){
         return angular.mock.inject(function ($injector,, _serviceUnderTest_) {
                mock = $injector.get('service_that_is_being_mocked');;                    
                service = __serviceUnderTest_;
            });
    }

    beforeEach(module('yourApp'));
    beforeEach(init());

    it('that has a then', function () {
       //arrange                   
        var spy= spyOn(mock, 'actionBeingCalled').and.callFake(function () {
            return {
                then: function (callback) {
                    return callback({'foo' : "bar"});
                }
            };
        });

        //act                
        var result = service.actionUnderTest(); // does cleverness

        //assert 
        expect(spy).toHaveBeenCalled();  
    });
});

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

A somewhat better solution:

atexit([] { system("PAUSE"); });

at the beginning of your program.

Pros:

  • can use std::exit()
  • can have multiple returns from main
  • you can run your program under the debugger
  • IDE independent (+ OS independent if you use the cin.sync(); cin.ignore(); trick instead of system("pause");)

Cons:

  • have to modify code
  • won't pause on std::terminate()
  • will still happen in your program outside of the IDE/debugger session; you can prevent this under Windows using:

extern "C" int __stdcall IsDebuggerPresent(void);
int main(int argc, char** argv) {
    if (IsDebuggerPresent())
        atexit([] {system("PAUSE"); });
    ...
}

Reset Windows Activation/Remove license key

  1. Open a command prompt as an Administrator.

  2. Enter slmgr /upk and wait for this to complete. This will uninstall the current product key from Windows and put it into an unlicensed state.

  3. Enter slmgr /cpky and wait for this to complete. This will remove the product key from the registry if it's still there.

  4. Enter slmgr /rearm and wait for this to complete. This is to reset the Windows activation timers so the new users will be prompted to activate Windows when they put in the key.

This should put the system back to a pre-key state.

Hope this helps you out!

How can I count the number of elements with same class?

You can get to the parent node and then query all the nodes with the class that is being searched. then we get the size

_x000D_
_x000D_
var parent = document.getElementById("parentId");_x000D_
var nodesSameClass = parent.getElementsByClassName("test");_x000D_
console.log(nodesSameClass.length);
_x000D_
<div id="parentId">_x000D_
  <p class="prueba">hello word1</p>_x000D_
  <p class="test">hello word2</p>_x000D_
  <p class="test">hello word3</p>_x000D_
  <p class="test">hello word4</p>_x000D_
</div>
_x000D_
_x000D_
_x000D_

ionic build Android | error: No installed build tools found. Please install the Android build tools

I Search this problem for days.... I hope it will be usefull

FINAL SOLUTION: (I assume that you have installed Oracle-JDK and ANDROID)

open /etc/environment with

 sudo nano /etc/environment


PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/home/shoniisra/Android/Sdk/tools:/home/shoniisra/Android/Sdk/platform-tools:/home/shoniisra/Android/Sdk/build-tools:/home/shoniisra/Android/Sdk:/home/shoniisra/android-studio/bin"
JAVA_HOME="/home/shoniisra/java/jdk1.8.0_231"
ANDROID_HOME="/home/shoniisra/Android/Sdk/build-tools/29.0.2"
ANDROID_SDK_ROOT="/home/shoniisra/Android/Sdk"
ANT_HOME="/home/shoniisra/ant/apache-ant-1.9.14"

Save and exit (CTRL+o CTRL+X)

Reload file source /etc/environment

If you recently installed Android you should accept some licences

cd ~/Android/Sdk/tools/bin/

Execute sdkmanager:

./sdkmanager --licenses

Then Accept all, and Finally generate your APK

cd {yourproyect}
sudo ionic cordova build android

Reading/Writing a MS Word file in PHP

I don't know what you are going to use it for, but I needed .doc support for search indexing; What I did was use a little commandline tool called "catdoc"; This transfers the contents of the Word document to plain text so it can be indexed. If you need to keep formatting and stuff this is not your tool.

Java check to see if a variable has been initialized

Instance variables or fields, along with static variables, are assigned default values based on the variable type:

  • int: 0
  • char: \u0000 or 0
  • double: 0.0
  • boolean: false
  • reference: null

Just want to clarify that local variables (ie. declared in block, eg. method, for loop, while loop, try-catch, etc.) are not initialized to default values and must be explicitly initialized.

Read whole ASCII file into C++ std::string

I don't think you can do this without an explicit or implicit loop, without reading into a char array (or some other container) first and ten constructing the string. If you don't need the other capabilities of a string, it could be done with vector<char> the same way you are currently using a char *.

converting string to long in python

Well, longs can't hold anything but integers.

One option is to use a float: float('234.89')

The other option is to truncate or round. Converting from a float to a long will truncate for you: long(float('234.89'))

>>> long(float('1.1'))
1L
>>> long(float('1.9'))
1L
>>> long(round(float('1.1')))
1L
>>> long(round(float('1.9')))
2L

What's the @ in front of a string in C#?

Since you explicitly asked for VB as well, let me just add that this verbatim string syntax doesn't exist in VB, only in C#. Rather, all strings are verbatim in VB (except for the fact that they cannot contain line breaks, unlike C# verbatim strings):

Dim path = "C:\My\Path"
Dim message = "She said, ""Hello, beautiful world."""

Escape sequences don't exist in VB (except for the doubling of the quote character, like in C# verbatim strings) which makes a few things more complicated. For example, to write the following code in VB you need to use concatenation (or any of the other ways to construct a string)

string x = "Foo\nbar";

In VB this would be written as follows:

Dim x = "Foo" & Environment.NewLine & "bar"

(& is the VB string concatenation operator. + could equally be used.)

ASP.Net MVC: Calling a method from a view

I tried lashrah's answer and it worked after changing syntax a little bit. this is what worked for me:

@(
  ((HomeController)this.ViewContext.Controller).Method1();
)

How to make IPython notebook matplotlib plot inline

To make matplotlib inline by default in Jupyter (IPython 3):

  1. Edit file ~/.ipython/profile_default/ipython_config.py

  2. Add line c.InteractiveShellApp.matplotlib = 'inline'

Please note that adding this line to ipython_notebook_config.py would not work. Otherwise it works well with Jupyter and IPython 3.1.0