Tutorial by Examples: e

PorterDuff.Mode is used to create a PorterDuffColorFilter. A color filter modifies the color of each pixel of a visual resource. ColorFilter filter = new PorterDuffColorFilter(Color.BLUE, PorterDuff.Mode.SRC_IN); The above filter will tint the non-transparent pixels to blue color. The color fil...

An Xfermode (think "transfer" mode) works as a transfer step in drawing pipeline. When an Xfermode is applied to a Paint, the pixels drawn with the paint are combined with underlying pixels (already drawn) as per the mode: paint.setColor(Color.BLUE); paint.setXfermode(new PorterDuffXferm...

Column aliases are used mainly to shorten code and make column names more readable. Code becomes shorter as long table names and unnecessary identification of columns (e.g., there may be 2 IDs in the table, but only one is used in the statement) can be avoided. Along with table aliases this allows ...

A simple literal function, printing Hello! to stdout: package main import "fmt" func main() { func(){ fmt.Println("Hello!") }() } play it on playground A literal function, printing the str argument to stdout: package main import "fmt&quot...

Warning: be sure you have at least 15 GB of free disk space. Compilation in Ubuntu >=13.04 Option A) Use Git Use git if you want to stay in sync with the latest Ubuntu kernel source. Detailed instructions can be found in the Kernel Git Guide. The git repository does not include necessary ...

In order to test the beginning and ending of a given string in Python, one can use the methods str.startswith() and str.endswith(). str.startswith(prefix[, start[, end]]) As it's name implies, str.startswith is used to test whether a given string starts with the given characters in prefix. >...

Strict mode can be applied on entire scripts by placing the statement "use strict"; before any other statements. "use strict"; // strict mode now applies for the rest of the script Strict mode is only enabled in scripts where you define "use strict". You can combin...

NaN ("Not a Number") is a special value defined by the IEEE Standard for Floating-Point Arithmetic, which is used when a non-numeric value is provided but a number is expected (1 * "two"), or when a calculation doesn't have a valid number result (Math.sqrt(-1)). Any equality or ...

Python's str type also features a number of methods that can be used to evaluate the contents of a string. These are str.isalpha, str.isdigit, str.isalnum, str.isspace. Capitalization can be tested with str.isupper, str.islower and str.istitle. str.isalpha str.isalpha takes no arguments and retu...

try { StyledDocument doc = new DefaultStyledDocument(); doc.insertString(0, "This is the beginning text", null); doc.insertString(doc.getLength(), "\nInserting new line at end of doc", null); MutableAttributeSet attrs = new SimpleAttributeSet(); StyleCons...

try { JTextPane pane = new JTextPane(); StyledDocument doc = new DefaultStyledDocument(); doc.insertString(0, "Some text", null); pane.setDocument(doc); //Technically takes any subclass of Document } catch (BadLocationException ex) { //hand...

StyledDocuments generally do not implement clone, and so have to copy them in a different way if that is necessary. try { //Initialization DefaultStyledDocument sourceDoc = new DefaultStyledDocument(); DefaultStyledDocument destDoc = new DefaultStyledDocument(); ...

There are several PHP functions that accept user-defined callback functions as a parameter, such as: call_user_func(), usort() and array_map(). Depending on where the user-defined callback function was defined there are different ways to pass them: Procedural style: function square($number) { ...

// zoo.php class Animal { public function eats($food) { echo "Yum, $food!"; } } $animal = new Animal(); $animal->eats('meat'); PHP knows what Animal is before executing new Animal, because PHP reads source files top-to-bottom. But what if we wanted to create ...

// Animal.php class Animal { public function eats($food) { echo "Yum, $food!"; } } // zoo.php require 'Animal.php'; $animal = new Animal; $animal->eats('slop'); // aquarium.php require 'Animal.php'; $animal = new Animal; $animal->eats('shrimp'); H...

// autoload.php spl_autoload_register(function ($class) { require_once "$class.php"; }); // Animal.php class Animal { public function eats($food) { echo "Yum, $food!"; } } // zoo.php require 'autoload.php'; $animal = new Animal; $animal->e...

// autoload.php spl_autoload_register(function ($class) { require_once "$class.php"; }); // Animal.php class Animal { public function eats($food) { echo "Yum, $food!"; } } // Ruminant.php class Ruminant extends Animal { public function eat...

Static methods and properties are defined on the class/constructor itself, not on instance objects. These are specified in a class definition by using the static keyword. class MyClass { static myStaticMethod() { return 'Hello'; } static get myStaticProperty() { r...

6 Fetch request promises initially return Response objects. These will provide response header information, but they don't directly include the response body, which may not have even loaded yet. Methods on the Response object such as .json() can be used to wait for the response body to load, then p...

An array in go is an ordered collection of same types elements. The basic notation to represent arrays is to use [] with the variable name. Creating a new array looks like var array = [size]Type, replacing size by a number (for example 42 to specify it will be a list of 42 elements), and replacing...