Tutorial by Examples: v

Sometimes we need to perform basic operations like hide/show view based on single value, for that single variable we cannot create model or it is not good practice to create model for that. DataBinding supports basic datatypes to perform those oprations. <layout xmlns:android="http://schema...
First Initialize FirebaseDatabase: FirebaseDatabase database = FirebaseDatabase.getInstance(); Write to your database: // Write a message to the database FirebaseDatabase database = FirebaseDatabase.getInstance(); DatabaseReference myRef = database.getReference("message"); myRef....
NIO appeared in Java 1.4 and introduced the concept of "Channels", which are supposed to be faster than regular I/O. Network-wise, the SelectableChannel is the most interesting as it allows to monitor different states of the Channel. It works in a similar manner as the C select() system ca...
You can retrieve the data stored at the located referenced by the pointer variable, using the ToString() method. The following example demonstrates this: using System; namespace UnsafeCodeApplication { class Program { public static void Main() { unsafe { ...
The PATH environment variable is generally defined in ~/.bashrc or ~/.bash_profile or /etc/profile or ~/.profile or /etc/bash.bashrc (distro specific Bash configuration file) $ echo $PATH /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/usr/lib/jv...
a Character evaluates to true if it's value is not zero, false if zero assert ! new Character((char)0) assert ! new Character('\u0000Hello Zero Char'.charAt(0)) assert new Character('Hello'.charAt(0))
a Matcher evaluates to true if it can find at least one match, false if no match is found // a match is found => true assert 'foo' =~ /[a-z]/ // the regexp does not match fully => no match => false assert !( 'foo' ==~ /[a-z]/ ) // a match is found => true assert 'foo' =~ /o/ // no...
The evaluation of a closure is the evaluation of the result of the closure. All rules applies : if the closure returns a null , zero number or empty String, Collection, Map or Array it evaluates to false otherwise to true. // Closure return non zero number => true assert { 42 }() // closure ...
There are frequent behavior patterns that can result in a lot of boilerplate code. By declaring a method that takes a Closure as a parameter, you can simplify your program. As an example, it is a common pattern to retrieve a database connection, start a transaction, do work, and then either commit ...
To remove a PATH from a PATH environment variable, you need to edit ~/.bashrc or ~/.bash_profile or /etc/profile or ~/.profile or /etc/bash.bashrc (distro specific) file and remove the assignment for that particular path. Instead of finding the exact assignment, you could just do a replacement in t...
app.ts import {Component} from '@angular/core'; import {Platform, ionicBootstrap} from 'ionic-angular'; import {StatusBar} from 'ionic-native'; import {LoginPage} from './pages/login/login'; import {FIREBASE_PROVIDERS, defaultFirebase, AuthMethods, AuthProviders, firebaseAuthConfig} from 'angul...
Information about a path can be get using the methods of a Path object: toString() returns the string representation of the path Path p1 = Paths.get("/var/www"); // p1.toString() returns "/var/www" getFileName() returns the file name (or, more specifically, the last ...
To interact with the filesystem you use the methods of the class Files. Checking existence To check the existence of the file or directory a path points to, you use the following methods: Files.exists(Path path) and Files.notExists(Path path) !Files.exists(path) does not neccesarily have t...
Elm defines the following special type variables that have a particular meaning to the compiler: comparable: Comprised of Int, Float, Char, String and tuples thereof. This allows the use of the < and > operators. Example: You could define a function to find the smallest and largest eleme...
$ printf -v now '%(%T)T' $ echo "$now" 12:42:47
C# inherits from C and C++ the usage of void* as a type-agnostic and size-agnostic pointer. void* ptr; Any pointer type can be assigned to void* using an implicit conversion: int* p1 = (int*)IntPtr.Zero; void* ptr = p1; The reverse requires an explicit conversion: int* p1 = (int*)IntPtr.Ze...
So, you have completed installation it's time now to Run you program with it. Netbeans has created a shortcut to your desktop, "Double click" that to open the IDE. To Create a new project 1. Click this button OR Goto: files >> New Project then this window will popup Select...
An implementation of IDatabaseInitializer that will use Code First Migrations to update the database to the latest version. To use this initializer you have to use DbMigrationsConfiguration type too. Usage: public class MyContext : DbContext { public MyContext() { Database.SetInitial...
CREATE TABLE [dbo].[MemOptimizedTemporalTable] ( [BusinessDocNo] [bigint] NOT NULL, [ProductCode] [int] NOT NULL, [UnitID] [tinyint] NOT NULL, [PriceID] [tinyint] NOT NULL, [SysStartTime] [datetime2](7) GENERATED ALWAYS AS ROW START NOT NULL, [SysEndTime] [datetime2](7...
This class enables a programmer to create an object and protect its confidentiality with a cryptographic algorithm. Given any Serializable object, one can create a SealedObject that encapsulates the original object, in serialized format (i.e., a "deep copy"), and seals (encrypts) its seri...

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