Tutorial by Examples: v

The Service Locator design pattern is very nearly dependency injection. Like the Bridge Pattern, this pattern can be used to reference platform-dependent code from a platform-independent context. Most interestingly, this pattern relies on the singleton pattern -- everything you put into the service ...

Mediator pattern defines an object (Mediator) that encapsulates how a set of objects interact. It enables many-to-many communication. UML diagram: Key components: Mediator: Defines an interface for communication between Colleagues. Colleague: Is an abstract class, which defines the events to b...

Installation npm install forever -g cd /node/project/directory Usages forever start app.js

To use the value stored in a variable, use the dollar sign followed by the variable name enclosed by parentheses or curly braces. x = hello y = $(x) # y now contains the value "hello" y = ${x} # parentheses and curly braces are treated exactly the same If a variable's name is only ...

Simply-expanded variables behave like variables from traditional programming languages. The expression on the right-hand side is evaluated, and the result is stored in the variable. If the right-hand side contains a variable reference, that variable is expanded before the assignment takes place. ...

When defining a recursively-expanded variable, the contents of the right-hand side are stored as-is. If a variable reference is present, the reference itself is stored (not the value of the variable). Make waits to expand the variable references until the variable is actually used. x = hello y =...

Within the context of an individual rule, Make automatically defines a number of special variables. These variables can have a different value for each rule in a makefile and are designed to make writing rules simpler. These variables can only be used in the recipe portion of a rule. VariableDesc...

The ?= operator is an extension that behaves like =, except that the assignment only occurs if the variable is not already set. x = hello x ?= world # $(x) will yield "hello"

The += operator is a common extension that adds the specified content to the end of the variable, separated by a space. x = hello x += world Variable references in the right-hand side will be expanded if and only if the original variable was defined as a simply-expanded variable.

Helpers and fakeApplication Class Helpers is used a lot for unit tests. It imitates a Play application, fakes HTTP requests and responses, session, cookies - all whatever may be needed for tests. A controller under the test should be executed in a context of a Play application. The Helpers method f...

This is such a common requirement in iOS development, and it was always something that had to be done purely in code (or using images - yuck!). Now it's incredibly easy to preview his kind of thing in Interface Builder, there's absolutely no excuse for not using it. Here's the code:- import UIKit ...

File Structure: pom.xml src/test/java/PlayStoreAutomation.java Launch command: mvn test -Dtest=PlayStoreAutomation PlayStoreAutomation.java import org.junit.AfterClass; import org.junit.BeforeClass; import org.junit.Test; import io.appium.java_client.android.AndroidDriver; import i...

The below example widget demonstrates how to format individual cells of a TreeView column conditionally, depending on value of the field in the particular cell. If value of field is negative, then it'll be displayed in red color and minus symbol will be hidden, otherwise it'll be displayed in normal...

The sequence for an error is usually: error is triggered by looking up the error name in errordict and executing this procedure. the errordict procedure calls signalerror, passing it the error name. signalerror takes snapshots of the stacks, saving the snapshots in $error, and then calls stop. ...

The documentation for docker events provides details, but when debugging it may be useful to launch a container and be notified immediately of any related event: docker run... & docker events --filter 'container=$(docker ps -lq)' In docker ps -lq, the l stands for last, and the q for quiet. Th...

Usually the case when one wants to change a field type to another, for instance the original collection may have "numerical" or "date" fields saved as strings: { "name": "Alice", "salary": "57871", "dob": "198...

Android Studio -> Preferences -> Gradle -> Tick Offline work and then restart your Android studio. Reference screenshot:

In order to put your view on top of every application, you have to assign your view to the corresponding window manager. For that you need the system alert permission, which can be requested by adding the following line to your manifest file: <uses-permission android:name="android.permissio...

You can get easily get this information by barfing out the input in your handler function. For example, in Java: public String handleRequest(String input, Context context) { context.getLogger().log("Input: " + input); String output = "Input:" + System.getProperty(&qu...

Just add this function to your functions.php. It will remove the version from all enqueued js and css files. function remove_cssjs_ver( $src ) { if( strpos( $src, '?ver=' ) ) $src = remove_query_arg( 'ver', $src ); return $src; } add_filter( 'style_loader_src', 'remove_cssjs_ver', 9...