Tutorial by Examples: st

Custom Camera Control - Mouse-based Sliding

Here's an example of a custom camera controller. This reads the position of the mouse within the client window, and then slides the camera around as if it were following the mouse on the window. index.html <html> <head> <title>Three.js Custom Mouse Camera Control Ex...

three.js • Camera Controls in Three.js

Discarding slow/outdated rest calls

A common usecase is to discard certain rest-calls, that are not needed any more after certain user-inputs. The most prominent example would be, when a user uses some search-function, makes a request, makes another request and for some reason the first request arrives after the second request and the...

rxjs • Common recipes

Locate a file on your system

Using bash you can easily locate a file with the locate command. For example say you are looking for the file mykey.pem: locate mykey.pem Sometimes files have strange names for example you might have a file like random7897_mykey_0fidw.pem. Let's say you're looking for this file but you only reme...

GNU/Linux • Shell

Using Packages to create classes with the same name

First Test.class: package foo.bar public class Test { } Also Test.class in another package package foo.bar.baz public class Test { } The above is fine because the two classes exist in different packages.

Java Language • Packages

Installation or Setup

jQuery plugins are typically installed via NPM or Yarn (if hosted there), or referencing an external script file containing the plugin, whether from a relative directory or a CDN. <script type="text/javascript" src="/path/to/plugin.jquery.js"></script>

jquery-plugins • Getting started with jquery-plugins

Unit testing with jest

Jest is a javascript testing framework widely used for testing react applications. Its supported by facebook Here's a test import 'react-native'; import React from 'react'; import Index from '../index.android.js'; import renderer from 'react-test-renderer'; it('renders correctly', () =>...

react-native • Unit Testing

Sending Downstream Messages using Postman

To do this in Postman, you simply have to set the following: Set request type to POST In the Headers, set the following: Content-Type = application/json Authorization = < Your FCM Server Key > (See your Firebase Console's Cloud Messaging Tab) Set the payload parameters in the Body...

firebase-cloud-messaging • Firebase Cloud Messaging

Saving this for use in nested functions / objects

One common pitfall is to try and use this in a nested function or an object, where the context has been lost. document.getElementById('myAJAXButton').onclick = function(){ makeAJAXRequest(function(result){ if (result) { // success this.className = 'success'; } }) }...

JavaScript • Context (this)

this in constructor functions

When using a function as a constructor, it has a special this binding, which refers to the newly created object: function Cat(name) { this.name = name; this.sound = "Meow"; } var cat = new Cat("Tom"); // is a Cat object cat.sound; // Returns "Meow" var ca...

JavaScript • Context (this)

Accessing the outer class from a non-static inner class

The reference to the outer class uses the class name and this public class OuterClass { public class InnerClass { public void method() { System.out.println("I can access my enclosing class: " + OuterClass.this); } } } You can access fields and ...

Java Language • Nested and Inner Classes

Elements of String

Elements of String are characters that can be accessed by the indexing operation string[index]. val str = "Hello, World!" println(str[1]) // Prints e String elements can be iterated with a for-loop. for (c in str) { println(c) }

Kotlin • Strings

String Literals

Kotlin has two types of string literals: Escaped string Raw string Escaped string handles special characters by escaping them. Escaping is done with a backslash. The following escape sequences are supported: \t, \b, \n, \r, \', \", \\ and \$. To encode any other character, use the Unicod...

Kotlin • Strings

String Templates

Both escaped strings and raw strings can contain template expressions. Template expression is a piece of code which is evaluated and its result is concatenated into string. It starts with a dollar sign $ and consists of either a variable name: val i = 10 val s = "i = $i" // evaluates to ...

Kotlin • Strings

String Equality

In Kotlin strings are compared with == operator which chect for their structural equality. val str1 = "Hello, World!" val str2 = "Hello," + " World!" println(str1 == str2) // Prints true Referential equality is checked with === operator. val str1 = ""&q...

Kotlin • Strings

Typical jQuery Plugin Structure

While writing jQuery plugins is simple, we want to enclose our plugins in a local scope. This will avoid namespace conflicts as well as polluting the global namespace, on top of ensuring that jQuery is loaded before our plugin extends it. // Encapsulate our plugins in a local scope (function($) { ...

jquery-plugins • Getting started with jquery-plugins

Convert tabs to spaces and spaces to tabs

You can convert tabs to spaces by doing the following: First check that expandtab is switched off :set noexpandtab Then :retab! which replaces spaces of a certain length with tabs If you enable expandtab again :set expandtab then and run the :retab! command then all the tabs becomes spaces...

vim • Whitespace

Creating Custom Error Messages in Model and in Controller

Let's say that you have the following class: public class PersonInfo { public int ID { get; set; } [Display(Name = "First Name")] [Required(ErrorMessage = "Please enter your first name!")] public string FirstName{ get; set; } [Display(Name = "L...

asp.net-mvc • Model validation

ConfigSlurper using string, number, boolean or list

In the file myConfig.groovy is the following content. message = 'Hello World!' aNumber=42 aBoolean=false aList=["apples", "grapes", "oranges"] Then in your main script you create a ConfigSlurper for your myConfig.groovy file which is really just another groovy sc...

groovy • Use ConfigSluper (instead of property files)

Without creating Stub or Java files

public String getCitiesByCountry(String countryName) throws MalformedURLException, IOException { //Code to make a webservice HTTP request String responseString = ""; String outputString = ""; String wsURL = "http://www.webservicex.com/globalweather.asm...

soap • Consuming SOAP Web Service

Examining the Structure of an Expression using Visitor

Define a new visitor class by overriding some of the methods of ExpressionVisitor: class PrintingVisitor : ExpressionVisitor { protected override Expression VisitConstant(ConstantExpression node) { Console.WriteLine("Constant: {0}", node); return base.VisitConstant(...

C# Language • Expression Trees