Tutorial by Examples: i

In Objective-C, method swizzling is the process of changing the implementation of an existing selector. This is possible due to the way Selectors are mapped on a dispatch table, or a table of pointers to functions or methods. Pure Swift methods are not dynamically dispatched by the Objective-C run...

git diff [HEAD|--staged...] --word-diff Rather than displaying lines changed, this will display differences within lines. For example, rather than: -Hello world +Hello world! Where the whole line is marked as changed, word-diff alters the output to: Hello [-world-]{+world!+} You can omit...

In this approach, the single is accessed via the static method: Singleton.getInstance(); To enforce only one instance of the singleton, a private static variable retains the instance, while any additional attempts to instantiate an instance are enforced within the constructor. package { publ...

Cocoa is Apple's API to develop apps for macOS, formerly known as OS X. Cocoa is a container framework, and contains three sub-frameworks. Foundation AppKit CoreData Cocoa Touch is Apple's version of Cocoa to develop apps for iOS, watchOS and tvOS. Cocoa Touch contains the same sub-framewo...

If you want to download an object from GCS that is publicly viewable, the simplest way is to use a web browser or a command line tool to fetch a URL with this pattern: https://storage.googleapis.com/bucketName/objectName. Example: https://storage.googleapis.com/pub/someOfTheTeam.jpg

You can use git merge --squash to squash changes introduced by a branch into a single commit. No actual commit will be created. git merge --squash <branch> git commit This is more or less equivalent to using git reset, but is more convenient when changes being incorporated have a symbolic...

This filter is very useful. One of the common problems for developers is how to include templates in plugins they develop. The filter is applied immediately after wordpress locates the appropriate template in the active child/parent theme using the wp hierarchy. Be careful to define when you want ...

git stash list This will list all stashes in the stack in reverse chronological order. You will get a list that looks something like this: stash@{0}: WIP on master: 67a4e01 Merge tests into develop stash@{1}: WIP on master: 70f0d95 Add user role to localStorage on user login You can refer t...

Applies the last stash without removing it from the stack git stash apply Or a specific stash git stash apply stash@{n}

function randomMinMax(min:Number, max:Number):Number { return (min + (Math.random() * Math.abs(max - min))); } This function is called by passing a range of minimum and maximum values. Example: randomMinMax(1, 10); Example outputs: 1.661770915146917 2.5521070677787066 9.4362709657...

function randomAngle():Number { return (Math.random() * 360); } Example outputs: 31.554428357630968 230.4078639484942 312.7964010089636

More complicated tests sometimes need to have things set up before you run the code you want to test. It is possible to do this in the test function itself, but then you end up with large test functions doing so much that it is difficult to tell where the setup stops and the test begins. You can als...

To ignore a file foo.txt in any directory you should just write its name: foo.txt # matches all files 'foo.txt' in any directory If you want to ignore the file only in part of the tree, you can specify the subdirectories of a specific directory with ** pattern: bar/**/foo.txt # matches all file...

Example that builds an executable (editor) and links a library (highlight) to it. Project structure is straightforward, it needs a master CMakeLists and a directory for each subproject: CMakeLists.txt editor/ CMakeLists.txt src/ editor.cpp highlight/ CMakeLists.txt in...

Multiple rows can be inserted with a single insert command: INSERT INTO tbl_name (field1, field2, field3) VALUES (1,2,3), (4,5,6), (7,8,9); For inserting large quantities of data (bulk insert) at the same time, DBMS-specific features and recommendations exist. MySQL - LOAD DATA INFILE MSSQL - B...

Travis CI has CMake 2.8.7 pre-installed. A minimal .travis.yml script for an out-of source build language: cpp compiler: - gcc before_script: # create a build folder for the out-of-source build - mkdir build # switch to build directory - cd build # run cmake; here we assume...

The CMake version preinstalled on Travis is very old. You can use the official Linux binaries to build with a newer version. Here is an example .travis.yml: language: cpp compiler: - gcc # the install step will take care of deploying a newer cmake version install: # first we creat...

int a = 1; int *a_pointer = &a; To dereference a_pointer and change the value of a, we use the following operation *a_pointer = 2; This can be verified using the following print statements. printf("%d\n", a); /* Prints 2 */ printf("%d\n", *a_pointer); /* Also prints...

If you need a completely customized view, you'll need to subclass View (the superclass of all Android views) and provide your custom sizing (onMeasure(...)) and drawing (onDraw(...)) methods: Create your custom view skeleton: this is basically the same for every custom view. Here we create the...

Custom views can also take custom attributes which can be used in Android layout resource files. To add attributes to your custom view you need to do the following: Define the name and type of your attributes: this is done inside res/values/attrs.xml (create it if necessary). The following file...