Tutorial by Examples: d

XML fragments, also known under the name of external parsed entities, can be stored in separate files. XML fragments, unlike XML documents, are less restrictive, in that several elements can appear top-level, as well as text nodes. Like an XML document, an external parsed entity may begin with an X...

// initialize pubnub object var pubnub = new PubNub({ subscribeKey: "yourSubscribeKey", publishKey: "myPublishKey" // optional }) // get up to the last 100 messages // published to the channel pubnub.history( { channel: 'channel1' }, func...

AndroidManifest.xml: <activity android:name="com.example.MainActivity" > <intent-filter> <action android:name="android.intent.action.VIEW" /> <category android:name="android.intent.category.DEFAULT" /> <c...

AndroidManifest.xml: <activity android:name="com.example.MainActivity" > <intent-filter> <action android:name="android.intent.action.VIEW" /> <category android:name="android.intent.category.DEFAULT" /> <c...

AndroidManifest.xml: <activity android:name="com.example.MainActivity" > <intent-filter> <action android:name="android.intent.action.VIEW" /> <category android:name="android.intent.category.DEFAULT" /> <categ...

AndroidManifest.xml: <activity android:name="com.example.MainActivity" > <intent-filter> <action android:name="android.intent.action.VIEW" /> <category android:name="android.intent.category.DEFAULT" /> <categ...

There is also the ability to evaluate expressions when naming methods similar to how you can access an objects' properties with []. This can be useful for having dynamic property names, however is often used in conjunction with Symbols. let METADATA = Symbol('metadata'); class Car { construct...

For programs with a single source file, using gcc is simple. /* File name is hello_world.c */ #include <stdio.h> int main(void) { int i; printf("Hello world!\n"); } To compile the file hello_world.c from the command line: gcc hello_world.c gcc will then compil...

Feature detection of classes can partly be done with the property_exists and method_exists functions. class MyClass { public $public_field; protected $protected_field; private $private_field; static $static_field; const CONSTANT = 0; public function public_function() {...

Here is a basic setting of the Header to change to a new page when a button is clicked. if(isset($_REQUEST['action'])) { switch($_REQUEST['action']) { //Setting the Header based on which button is clicked case 'getState': header("Location: http://NewPageForSta...

Retrieve the last ID generated by an INSERT query on a table with an AUTO_INCREMENT column. Object-oriented Style $id = $conn->insert_id; Procedural Style $id = mysqli_insert_id($conn); Returns zero if there was no previous query on the connection or if the query did not update an AUTO...

There are three ways to set the classpath. It can be set using the CLASSPATH environment variable : set CLASSPATH=... # Windows and csh export CLASSPATH=... # Unix ksh/bash It can be set on the command line as follows java -classpath ... javac -classpath ... Note ...

If you want to add all the JARs in directory to the classpath, you can do this concisely using classpath wildcard syntax; for example: someFolder/* This tells the JVM to add all JAR and ZIP files in the someFolder directory to the classpath. This syntax can be used in a -cp argument, a CLASSPA...

Sometimes, just adding all the JARs from a folder isn't enough, for example when you have native code and need to select a subset of JARs. In this case, you need two main() methods. The first one builds a classloader and then uses this classloader to call the second main(). Here is an example which...

CSS div { height: 200px; width: 200px; background: url(http://lorempixel.com/200/200/nature/1); mask-image: linear-gradient(to right, white, transparent); } HTML <div></div> In the above example there is an element with an image as its background. The mask that is a...

The content mode property of a view tells how its content should be laid out. In the Interface Builder, the various modes can be selected in the Attributes Inspector. Let's use two image views to see how the various modes work. Scale to Fill The image heights and widths are stretched to mat...

The following might have undefined behavior due to incorrect pointer alignment: char *memory_block = calloc(sizeof(uint32_t) + 1, 1); uint32_t *intptr = (uint32_t*)(memory_block + 1); /* possible undefined behavior */ uint32_t mvalue = *intptr; The undefined behavior happens as the pointer...

The following code has undefined behavior: char buffer[6] = "hello"; char *ptr1 = buffer - 1; /* undefined behavior */ char *ptr2 = buffer + 5; /* OK, pointing to the '\0' inside the array */ char *ptr3 = buffer + 6; /* OK, pointing to just beyond */ char *ptr4 = buffer + 7; /* un...

An extension to PHP called Xdebug is available to assist in profiling PHP applications, as well as runtime debugging. When running the profiler, the output is written to a file in a binary format called "cachegrind". Applications are available on each platform to analyze these files. To...

for /r command can be used to recursively visit all the directories in a directory tree and perform a command. @echo off rem start at the top of the tree to visit and loop though each directory for /r %%a in (.) do ( rem enter the directory pushd %%a echo In directory: cd rem leave...