Subclassing NSObject in Swift - Best Practice with Initializers

Here is the layout of an example Class, can someone guide me on what's best practice when creating a subclass of NSObject?

class MyClass: NSObject {

var someProperty: NSString! = nil

override init() {
self.someProperty = "John"
super.init()
}

init(fromString string: NSString) {
self.someProperty = string
super.init()
}

}

Is this correct, am I following best practice here?

I wonder if I'm correctly setting up the initializers (one that sets the string to a default, and one which I can pass in a string)?

Should I call `super.init()` at the end of each of the initializers?

Should my more **specific** (the one that takes a string) initializer simply call `self.init()` at the end rather than `super.init()`?

What is the right way to set up the initializers in Swift when subclassing `NSObject`? - and how should I call the super init ?

This question (albeit in Objective C) suggests you should have an init, which you always call and simply set the properties in more specific inits:

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I'm not Swift ninja but I would write `MyClass` as:

class MyClass: NSObject {

var someProperty: NSString // no need (!). It will be initialised from controller

init(fromString string: NSString) {
self.someProperty = string
super.init() // can actually be omitted in this example because will happen automatically.
}

convenience override init() {
self.init(fromString:"John") // calls above mentioned controller with default name
}
}

----

See the [initialization section of the documentation][1]


[1]:

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In complement to the answers, a good idea is to call super.init() *before* other statements. I think it's a stronger requirement in Swift because allocations are implicit.

If someProperty can be nil, then I think you want to define the property as:

var someProperty: NSString?

This also eliminates the need for a custom initializer (at least, for this property), since the property doesn't require a value at initialization time.