Tutorial by Examples: w

When an API is marked with NS_REFINED_FOR_SWIFT, it will be prefixed with two underscores (__) when imported to Swift: @interface MyClass : NSObject - (NSInteger)indexOfObject:(id)obj NS_REFINED_FOR_SWIFT; @end The generated interface looks like this: public class MyClass : NSObject { publ...

All Kotlin programs start at the main function. Here is an example of a simple Kotlin "Hello World" program: package my.program fun main(args: Array<String>) { println("Hello, world!") } Place the above code into a file named Main.kt (this filename is entirel...

// Check if service worker is available. if ('serviceWorker' in navigator) { navigator.serviceWorker.register('/sw.js').then(function(registration) { console.log('SW registration succeeded with scope:', registration.scope); }).catch(function(e) { console.log('SW registration failed...

In this case, building against API 23, so permissions are handled too. You must add in the Manifest the following permission (wherever the API level you're using): <uses-permission android:name="android.permission.CAMERA"/> We're about to create an activity (Camera2Activity.java...

In this example, we can use GROUP BY not only determined the sort of the rows returned, but also what rows are returned, since we're using TOP to limit the result set. Let's say we want to return the top 5 highest reputation users from an unnamed popular Q&A site. Without ORDER BY This query ...

This uses the Dropbox .NET SDK to download a file from the Dropbox API at the remote path /Homework/math/Prime_Numbers.txt to the local file Prime_Numbers.txt: using (var response = await client.Files.DownloadAsync("/Homework/math/Prime_Numbers.txt")) { using (var fileStream = File....

This uses the Dropbox Python SDK to create a shared link for a file and also supplies a requested visibility and expiration in the settings: import datetime import dropbox dbx = dropbox.Dropbox("<ACCESS_TOKEN>") expires = datetime.datetime.now() + datetime.timedelta(days=30...

Note: The width and height attributes are not deprecated on images and never have been. Their use has been made much stricter though. The dimensions of an image can be specified using the width and height attributes of the image tag: <img src="images/200x200-img.png" width="2...

Let's say you want to generate counts or subtotals for a given value in a column. Given this table, "Westerosians": NameGreatHouseAllegienceAryaStarkCerceiLannisterMyrcellaLannisterYaraGreyjoyCatelynStarkSansaStark Without GROUP BY, COUNT will simply return a total number of rows: SELE...

Syntax for accessing rows and columns: [, [[, and $ This topic covers the most common syntax to access specific rows and columns of a data frame. These are Like a matrix with single brackets data[rows, columns] Using row and column numbers Using column (and row) names Like a list: Wi...

var widget = $( "#accordion" ).accordion( "widget" ); This method returns a jQuery object containing the accordion.

Switch statements compare the value of an expression against 1 or more values and executes different sections of code based on that comparison. var value = 1; switch (value) { case 1: console.log('I will always run'); break; case 2: console.log('I will never run'); break;...

First, create a new SoapClient object, passing the URL to the WSDL file and optionally, an array of options. // Create a new client object using a WSDL URL $soap = new SoapClient('https://example.com/soap.wsdl', [ # This array and its values are optional 'soap_version' => SOAP_1_2, ...

This is similar to WSDL mode, except we pass NULL as the WSDL file and make sure to set the location and uri options. $soap = new SoapClient(NULL, [ 'location' => 'https://example.com/soap/endpoint', 'uri' => 'namespace' ]);

Steam has a games under $10 section of their store page. Somewhere deep in the heart of their systems, there's probably a query that looks something like: SELECT * FROM Items WHERE Price < 10

Available in the standard library as defaultdict from collections import defaultdict d = defaultdict(int) d['key'] # 0 d['key'] = 5 d['key'] # 5 d = defaultdict(lambda: 'empty') d['key'] # 'empty' d['key'] = 'full' ...

When ASP.NET handles a request, a thread is assigned from the thread pool and a request context is created. The request context contains information about the current request which can be accessed through the static HttpContext.Current property. The request context for the request is then assigned t...

Most browsers support using color keywords to specify a color. For example, to set the color of an element to blue, use the blue keyword: .some-class { color: blue; } CSS keywords are not case sensitive—blue, Blue and BLUE will all result in #0000FF. Color Keywords Color nameHex valueRGB...

The Edges The browser creates a rectangle for each element in the HTML document. The Box Model describes how the padding, border, and margin are added to the content to create this rectangle. Diagram from CSS2.2 Working Draft The perimeter of each of the four areas is called an edge. Each edge ...

Given a function that accepts a Node-style callback, fooFn(options, function callback(err, result) { ... }); you can promisify it (convert it to a promise-based function) like this: function promiseFooFn(options) { return new Promise((resolve, reject) => fooFn(options, (err, re...