Tutorial by Examples: t

If you want to change an attribute of a control such as a textbox or label from another thread than the GUI thread that created the control, you will have to invoke it or else you might get an error message stating: "Cross-thread operation not valid: Control 'control_name' accessed from a th...

This example will show you how you can resolve data fetched from a service before rendering your application's view. Uses angular/router 3.0.0-beta.2 at the time of writing users.service.ts ... import { Http, Response } from '@angular/http'; import { Observable } from 'rxjs/Rx'; import { User ...

using System; using System.IO; public class Program { public static void Main() { string filePath = "somePath"; if(File.Exists(filePath)) { Console.WriteLine("Exists"); } else ...

Methods are defined with the def keyword, followed by the method name and an optional list of parameter names in parentheses. The Ruby code between def and end represents the body of the method. def hello(name) "Hello, #{name}" end A method invocation specifies the method name, the...

Many functions in Ruby accept a block as an argument. E.g.: [0, 1, 2].map {|i| i + 1} => [1, 2, 3] If you already have a function that does what you want, you can turn it into a block using &method(:fn): def inc(num) num + 1 end [0, 1, 2].map &method(:inc) => [1, 2, 3]...

There are three basic rules of semicolon insertion: When, as the program is parsed from left to right, a token (called the offending token) is encountered that is not allowed by any production of the grammar, then a semicolon is automatically inserted before the offending token if one or more o...

empty statement var statement expression statement do-while statement continue statement break statement return statement throw statement Examples: When the end of the input stream of tokens is encountered and the parser is unable to parse the input token stream as a single complete Pro...

$string = "a;b;c\nd;e;f"; // $1, $2 and $3 represent the first, second and third capturing groups echo preg_replace("(^([^;]+);([^;]+);([^;]+)$)m", "$3;$2;$1", $string); Outputs c;b;a f;e;d Searches for everything between semicolons and reverses the order.

// 1. Instantiate an AlertDialog.Builder with its constructor // the parameter this is the context (usually your activity) AlertDialog.Builder builder = new AlertDialog.Builder(this); // 2. Chain together various setter methods to set the dialog characteristics builder.SetMessage(Resource.Str...

HBase Standalone is a mode which allow you to get rid of HDFS and to test HBase before deploying in a cluster, It is not production oriented. Installing HBase in standalone is extremely simple. First you have to download the HBase archive named hbase-X.X.X-bin.tar.gz available on one of the apache ...

In performing parsing, before starting, the grammar for the language needs to be specified. A source of tokens is also needed for the parser. The parser could be hand-written code, or a parser generator tool could be used. If a parser generator tool is used, then that tool will need to be downloade...

Sharing a simple string was easy, but you can do much more. In this example, I'll also store a complete array of strings, along with a gradient brush to be used for the background. This should give you a pretty good idea of just how much you can do with resources: <Window x:Class="WPFApplic...

If you only need a given resource for a specific control, you can make it more local by adding it to this specific control, instead of the window. It works exactly the same way, the only difference being that you can now only access from inside the scope of the control where you put it: <StackPa...

Polymorphism is one of the pillar of OOP. Poly derives from a Greek term which means 'multiple forms'. Below is an example which exhibits Polymorphism. The class Vehicle takes multiple forms as a base class. The Derived classes Ducati and Lamborghini inherits from Vehicle and overrides the base cl...

in this way '0' representing the known values ​​are ranked first, '1' representing the NULL values ​​are sorted by the last: SELECT ID ,REGION ,CITY ,DEPARTMENT ,EMPLOYEES_NUMBER FROM DEPT ORDER BY CASE WHEN REGION IS NULL THEN 1 ELSE 0 END, REGION ...

If you need to send events from fragment to activity, one of the possible solutions is to define callback interface and require that the host activity implement it. Example Send callback to an activity, when fragment's button clicked First of all, define callback interface: public interface Samp...

CREATE TABLE ( id INT UNSIGNED NOT NULL AUTO_INCREMENT, ... PRIMARY KEY(id), ... ); Main notes: Starts with 1 and increments by 1 automatically when you fail to specify it on INSERT, or specify it as NULL. The ids are always distinct from each other, but... Do not make a...

The ToString method on an enum returns the string name of the enumeration. For instance: Module Module1 Enum Size Small Medium Large End Enum Sub Main() Dim shirtSize As Size = Size.Medium Dim output As String = shirtSize.ToString() ...

The following examples use the UTF-8 encoding to represent filenames (and directory names) on disk. If you want to use another encoding, you should use Encode::encode(...). use v5.14; # Make Perl recognize UTF-8 encoded characters in literal strings. # For this to work: Make sure your text-editor...

The quotes property is used to customize the opening and closing quotation marks of the <q> tag. q { quotes: "«" "»"; }