When should super init be called?
The Swift programming language says a lot about class initializations. Class objects are initialized in two phases. In the first phase, each stored property is assigned an initial value by the class that introduced it.
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Why do we need initialization in Swift?
Swift defines two types of initializers for class types to help ensure that all stored properties receive an initial value. Designated initializers are the main initializers of a class. You can also define a convenience initializer to create an instance of that class for a specific use case or input value type.
What should a convenience initializer call?
A convenience initializer is a secondary initializer that must call a named initializer of the same class. It is useful when you want to provide default values or other custom settings. A class does not require any convenient initializers.
What is the purpose of initializers?
Initialization is the process of locating and using defined values for variable data used by a computer program. For example, an operating system or application program is installed with default or user-specified values that determine certain aspects of how the system or program will function.
What does super()__Init__ do?
__init__() of the superclass ( Square ) will be called automatically. super() returns a delegate object to a parent class, so you call the method you want directly on it: super() . This is especially useful when you have multiple subclasses that inherit from a superclass.
What is super init() Swift?
The init() initializer for Bicycle starts by calling super. init(), which calls the default initializer for the Bicycle class’s superclass, Vehicle. This ensures that Vehicle initializes the numberOfWheels inherited property before Bicycle has a chance to modify the property.
What is a convenience startup called?
All you have to do is instantiate the superclass, using the init convenience, right at the start of the subclass. It then calls the designated startup of the super using the instance you just created.
How do you write a convenience startup Swift?
Usage examples class Player { let name: String let level: Int init(name: String, level: Int) { self.name = name self. level = level } //Add the convenience keyword convenience init(name: String) { self. init(name: name, level: 0) //Yes! Now I can call my initializer partner! } }