How to create a singleton in Swift
A step by step tutorial on creating a singleton in Swift (iOS). Github repository available.
The following tutorial builds on our starter project and covers the creation of a singleton through the example of a LanguageCoordinator.
If you are looking for the specific code, please jump to Step Four.
Step One: Create the folder for the singleton
We recommend that you create a folder for your singleton and all associated functionality.
Step Two: Create the file for the singleton
Select your folder and press Command + N to create a file and press next.
Please note that this assumes that a Swift file is auto selected.
Step Three: Name & create the singleton file
Name your singleton and press Create.
Step Four: Code your singleton
Code your class and functionality.
To make it a singleton, add the following line - which makes the singleton accessible via the .shared parameter - i.e. LanguageCoordinator.shared. You can call this whatever you like, i.e. singleton would be accessed by LanguageCoordinator.singleton.
Alternatively, copy and add to the gist below.
Step Five: Verify
Call a function or variable within your singleton within a part of your app to verify that it's been setup correctly.
In our example we call the LanguageCoordinator singleton initialize function from the ViewController on ViewDidLoad.
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Any Questions
We are actively looking for feedback on how to improve this resource. Please send us a note to inquiries@delasign.com with any thoughts or feedback you may have.