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It is unlikely that someone uses an unsupported version of Django, and at his own risks. If ever someone does, it must be his concern to know if a feature exists in the given version. Considering the above, it is useless to mention specificities of an unsupported version. 1.6 This kind of block i...

What is JNA? Java Native Access (JNA) is a community-developed library providing Java programs an easy access to native shared libraries (.dll files on windows, .so files on Unix ...) How can I use it? Firstly, download the latest release of JNA and reference its jna.jar in your project's CLA...

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...

It's possible to clear complex shaped regions by changing the globalCompositeOperation property. // All pixels being drawn will be transparent ctx.globalCompositeOperation = 'destination-out'; // Clear a triangular section ctx.globalAlpha = 1; // ensure alpha is 1 ctx.fillStyle = '#000'; /...

Hi everyone! This is a demo I love running for people that get started with BigQuery. So let's run some simple queries to get you started. Setup You will need a Google Cloud project: Go to http://bigquery.cloud.google.com/. If it tells you to create a project, follow the link to create a proje...

RxSwift provides not only the ways to control your data, but to represent user actions in a reactive way also. RxCocoa contains everything you need. It wraps most of the UI components' properties into Observables, but not really. There are some upgraded Observables called ControlEvents (which repre...

While Runnable provides a means to wrap code to be executed in a different thread, it has a limitation in that it cannot return a result from the execution. The only way to get some return value from the execution of a Runnable is to assign the result to a variable accessible in a scope outside of t...

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...

To make a jar, you need one or more class files. This should have a main method if it is to be run by a double click. For this example, we will use: import javax.swing.*; import java.awt.Container; public class HelloWorld { public static void main(String[] args) { JFrame f = ne...

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 keyword denoting one of the two possible values of type bool. bool ok = true; if (!f()) { ok = false; goto end; }

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; }

A specifier that can be applied to the declaration of a non-static, non-reference data member of a class. A mutable member of a class is not const even when the object is const. class C { int x; mutable int times_accessed; public: C(): x(0), times_accessed(0) { } int get...

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...

This is a mistake that causes real confusion for Java beginners, at least the first time that they do it. Instead of writing this: if (feeling == HAPPY) System.out.println("Smile"); else System.out.println("Frown"); they accidentally write this: if (feeling == HAP...

const url = 'http://api.stackexchange.com/2.2/questions?site=stackoverflow&tagged=javascript'; const questionList = document.createElement('ul'); document.body.appendChild(questionList); const responseData = fetch(url).then(response => response.json()); responseData.then(({item...

5.6 PHP 5.6 introduced variable-length argument lists (a.k.a. varargs, variadic arguments), using the ... token before the argument name to indicate that the parameter is variadic, i.e. it is an array including all supplied parameters from that one onward. function variadic_func($nonVariadic, ...$...

#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...