Swift MKAnnotationView WTF

MKAnnotationView-v1.swift

/*
  MKAnnotationView has one init listed in its documentation, initWithAnnotation:reuseIdentifier:, so let's override that.
  But this causes a runtime exception:

  fatal error: use of unimplemented initializer 'init(frame:)' for class 'PulsatingDotMarker'
*/

class PulsatingDotMarker: MKAnnotationView {

    let innerCircle: UIView
    let outerCircle: UIView

    override init!(annotation: MKAnnotation!, reuseIdentifier: String!) {
        innerCircle = ...
        outerCircle = ...

        super.init(annotation: annotation, reuseIdentifier: reuseIdentifier)
    }

    ...
}

MKAnnotationView-v2.swift

/*
  Ok, I guess initWithAnnotation:reuseIdentifier: internally calls initWithFrame:, so it's probably that one that I should
  override instead. So let's do that.

  Nice try - compile error: "Extra argument 'reuseIdentifier' in call" when creating the object... So if I implement the (required)
  initializer initWithFrame:, it now loses the default initializer initWithAnnotation:reuseIdentifier:, wtf?
*/

class PulsatingDotMarker: MKAnnotationView {

    let innerCircle: UIView
    let outerCircle: UIView

    override init(frame: CGRect) {
        innerCircle = ...
        outerCircle = ...

        super.init(frame: frame)
    }

    ...
}

MKAnnotationView-v3.swift

/*
  Maybe if I added an override of initWithAnnotation:reuseIdentifier: that just calls super it will be available again?

  Nope, still not good - compile error: "Property 'self.innerCircle' not initialized at super.init call". Well, duh, it isn't,
  because it's only set in initWithFrame: which you told me to implement...
*/

class PulsatingDotMarker: MKAnnotationView {

    let innerCircle: UIView
    let outerCircle: UIView

    init!(annotation: MKAnnotation!, reuseIdentifier: String!) {
        super.init(annotation: annotation, reuseIdentifier: reuseIdentifier)
    }

    override init(frame: CGRect) {
        innerCircle = ...
        outerCircle = ...

        super.init(frame: frame)
    }

    ...
}

MKAnnotationView-v4.swift

/*
  What if I had an initWithFrame:, but initialized the subviews in initWithAnnotation:reuseIdentifier:? But then what if someone
  just calls initWithFrame: directly, which they can do since I explicitly made that initializer available (because I had to)?

  Yeah, of course, Swift protects me from that too by telling me "Property 'self.innerCircle' not initialized at super.init call"
  again, this time in initWithFrame:...

  So what am I supposed to do? I can't create the subviews both here and there, right?
*/

class PulsatingDotMarker: MKAnnotationView {

    let innerCircle: UIView
    let outerCircle: UIView

    init!(annotation: MKAnnotation!, reuseIdentifier: String!) {
        innerCircle = ...
        outerCircle = ...

        super.init(annotation: annotation, reuseIdentifier: reuseIdentifier)
    }

    override init(frame: CGRect) {
        super.init(frame: frame)
    }

    ...
}

MKAnnotationView-v5.swift

/*
  And surprise surprise, this works - even though I'm assigning a constant property twice in the same object (?!?!).
*/

class PulsatingDotMarker: MKAnnotationView {

    let innerCircle: UIView
    let outerCircle: UIView

    init!(annotation: MKAnnotation!, reuseIdentifier: String!) {
        innerCircle = ...
        outerCircle = ...

        super.init(annotation: annotation, reuseIdentifier: reuseIdentifier)
    }

    override init(frame: CGRect) {
        innerCircle = ...
        outerCircle = ...

        super.init(frame: frame)
    }

    ...
}