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It's possible to write directly to the rendered image data using putImageData. By creating new image data then assigning it to the canvas, you will clear the entire screen. var imageData = ctx.createImageData(canvas.width, canvas.height); ctx.putImageData(imageData, 0, 0); Note: putImageData is...

Prior to Java 5's concurrent package introduction threading was more low level.The introduction of this package provided several higher level concurrent programming aids/constructs. Locks are thread synchronisation mechanisms that essentially serve the same purpose as synchronized blocks or key wor...

Starting with the Support Library version 22.2.1, it's possible to show and hide a FloatingActionButton from scrolling behavior using a FloatingActionButton.Behavior sublclass that takes advantage of the show() and hide() methods. Note that this only works with a CoordinatorLayout in conjunction wi...

A floating point type. Has the narrowest range out of the three floating point types in C++. float area(float radius) { const float pi = 3.14159f; return pi*radius*radius; }

In R, data objects are manipulated using named data structures. The names of the objects might be called "variables" although that term does not have a specific meaning in the official R documentation. R names are case sensitive and may contain alphanumeric characters(a-z,A-z,0-9), the dot...

#include <stdio.h> #define SIZE (10) int main() { size_t i = 0; int *p = NULL; int a[SIZE]; /* Setting up the values to be i*i */ for(i = 0; i < SIZE; ++i) { a[i] = i * i; } /* Reading the values using pointers */ for(p =...

You can define the signing configuration to sign the apk in the build.gradle file. You can define: storeFile : the keystore file storePassword: the keystore password keyAlias: a key alias name keyPassword: A key alias password You have to define the signingConfigs block to create a signin...

You can define the signing configuration in an external file as a signing.properties in the root directory of your project. For example you can define these keys (you can use your favorite names): STORE_FILE=myStoreFileLocation STORE_PASSWORD=myStorePassword KEY_ALIAS=myKeyAlias KEY_PASSWOR...

You can store the signing information setting environment variables. These values can be accessed with System.getenv("<VAR-NAME>") In your build.gradle you can define: signingConfigs { release { storeFile file(System.getenv("KEYSTORE")) storePasswo...

The Repeat command, executed with the dot or period key (.), is more useful than it first appears. Once learned, you will find yourself using it often. Command:Description.Repeat the last change10.Repeat the last change 10 times So then, for a very simple example, if you make a change to line 1 by...

You can define a method to accept an arbitrary number of keyword arguments using the double splat (**) operator: def say(**args) puts args end say foo: "1", bar: "2" # {:foo=>"1", :bar=>"2"} The arguments are captured in a Hash. You can manip...

SQLite has no separate data type for date or time values. ISO8601 strings The built-in keywords CURRENT_DATE, CURRENT_TIME, and CURRENT_TIMESTAMP return strings in ISO8601 format: > SELECT CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP; CURRENT_DATE CURRENT_TIME CURRENT_TIMESTAMP --------...

The static storage class specifier has three different meanings. Gives internal linkage to a variable or function declared at namespace scope. // internal function; can't be linked to static double semiperimeter(double a, double b, double c) { return (a + b + c)/2.0; } // exported to c...

This is very similar to using an Application subclass and overriding the attachBaseContext() method. However, using this method, you don't need to override attachBaseContext() as this is already done in the MultiDexApplication superclass. Extend MultiDexApplication instead of Application: package...

Automapper can be installed from nuget running the following command in Package Manager Console: Install-Package AutoMapper Then it can be included in different files within the project it has been installed to by using directives: using AutoMapper;

Unlike a parallel for-loop (parfor), which takes the iterations of a loop and distributes them among multiple threads, a single program, multiple data (spmd) statement takes a series of commands and distributes them to all the threads, so that each thread performs the command and stores the results....

Using Alternatives Many Linux distributions use the alternatives command for switching between different versions of a command. You can use this for switching between different versions of Java installed on a machine. In a command shell, set $JDK to the pathname of a newly installed JDK; e.g....

If you need to copy a database from one server to another, you have two options: Option 1: Store the dump file in the source server Copy the dump file to your destination server Load the dump file into your destination server On the source server: mysqldump [options] > dump.sql On th...

Below is example of service decorator, overriding null date returned by service. angular.module('app', []) .config(function($provide) { $provide.decorator('myService', function($delegate) { $delegate.getDate = function() { // override with actual date object return new Date(...

Map has three methods which returns iterators: .keys(), .values() and .entries(). .entries() is the default Map iterator, and contains [key, value] pairs. const map = new Map([[1, 2], [3, 4]]); for (const [key, value] of map) { console.log(`key: ${key}, value: ${value}`); // logs: // ke...