Tutorial by Topics: ion

Note that a ViewTreeObserver instance associated with a View instance can become invalid while that View is still alive. From the View.getViewTreeObserver javadocs: // The returned ViewTreeObserver observer is not guaranteed to remain // valid for the lifetime of this View. If the caller of this...

A regular expression is a special sequence of characters that helps in matching or finding other strings or sets of strings, using a specialized syntax held in a pattern. Java has support for regular expression usage through the java.util.regex package. This topic is to introduce and help developers...

Optional is a container object which may or may not contain a non-null value. If a value is present, isPresent() will return true and get() will return the value. Additional methods that depend on the presence of the contained value are provided, such as orElse(), which returns a default value if v...

Using HttpUrlConnection on Android requires that you add the Internet permission to your app (in the AndroidManifest.xml). There are also other Java HTTP clients and libraries, such as Square's OkHttp, which are easier to use, and may offer better performance or more features.

In Java, an annotation is a form of syntactic metadata that can be added to Java source code. It provides data about a program that is not part of the program itself. Annotations have no direct effect on the operation of the code they annotate. Classes, methods, variables, parameters and packages ar...

An Android application needs to run on all kinds of devices. Each device may have a different version on Android running on it. Now, each Android version might not support all the features that your app requires, and so while building an app, you need to keep the minimum and maximum Android version...

RMI requires 3 components: client, server and a shared remote interface. The shared remote interface defines the client-server contract by specifying the methods a server must implement. The interface must be visible to the server so that it can implement the methods; the interface must be visible...

JavaScriptSerializer vs Json.NET The JavaScriptSerializer class was introducted in .NET 3.5 and is used internally by .NET's asynchronous communication layer for AJAX-enabled applications. It can be used to work with JSON in managed code. Despite the existence of the JavaScriptSerializer class,...

Functions in JavaScript provide organized, reusable code to perform a set of actions. Functions simplify the coding process, prevent redundant logic, and make code easier to follow. This topic describes the declaration and utilization of functions, arguments, parameters, return statements and scope ...

List comprehensions in Python are concise, syntactic constructs. They can be utilized to generate lists from other lists by applying functions to each element in the list. The following section explains and demonstrates the use of these expressions. [x + 1 for x in (1, 2, 3)] # list comprehen...

PHP's functional programming relies on functions. Functions in PHP provide organized, reusable code to perform a set of actions. Functions simplify the coding process, prevent redundant logic, and make code easier to follow. This topic describes the declaration and utilization of functions, argument...

When using boolean coercion, the following values are considered "falsy": false 0 "" (empty string) null undefined NaN (not a number, e.g. 0/0) document.all¹ (browser context) Everything else is considered "truthy". ¹ willful violation of the ECMAScript ...

Conditional expressions, involving keywords such as if and else, provide JavaScript programs with the ability to perform different actions depending on a Boolean condition: true or false. This section covers the use of JavaScript conditionals, Boolean logic, and ternary statements. if (conditi...

Functions in Python provide organized, reusable and modular code to perform a set of specific actions. Functions simplify the coding process, prevent redundant logic, and make the code easier to follow. This topic describes the declaration and utilization of functions in Python. Python has many bui...

let regex = /pattern/[flags] let regex = new RegExp('pattern', [flags]) let ismatch = regex.test('text') let results = regex.exec('text') FlagsDetailsgglobal. All matches (don't return on the first match).mmulti-line. Causes ^ & $ to match the begin/end of each line (not only begin/e...

“ An optional value either contains a value or contains nil to indicate that a value is missing” Excerpt From: Apple Inc. “The Swift Programming Language (Swift 3.1 Edition).” iBooks. https://itun.es/us/k5SW7.l Basic optional use cases include: for a constant (let), use of an optional within a loo...

Function pointers are pointers that point to functions instead of data types. They can be used to allow variability in the function that is to be called, at run-time. returnType (*name)(parameters) typedef returnType (*name)(parameters) typedef returnType Name(parameters); Name *n...

VersionRelease DatePrivate Beta2016-03-2612016-07-2522016-08-0432016-08-2942016-09-1252016-09-2962016-10-2072016-11-29