initialization - what initializers should a MKAnnotationView subclass have in Swift? -

i'm creating subclass of mkannotationview in project. needs have 2 properties storing subviews need initialize somewhere @ beginning.

mkannotationview has 1 initializer listed in documentation, initwithannotation:reuseidentifier:, figured i'd override that:

class pulsatingdotmarker: mkannotationview {      let innercircle: uiview     let outercircle: uiview      override init!(annotation: mkannotation!, reuseidentifier: string!) {         innercircle = ...         outercircle = ...          super.init(annotation: annotation, reuseidentifier: reuseidentifier)     }      ... } 

but causes runtime exception:

fatal error: use of unimplemented initializer 'init(frame:)' class 'pulsatingdotmarker'

ok, guess initwithannotation:reuseidentifier: internally calls initwithframe:, it's 1 should override instead. let's try that:

class pulsatingdotmarker: mkannotationview {      let innercircle: uiview     let outercircle: uiview      override init(frame: cgrect) {         innercircle = ...         outercircle = ...          super.init(frame: frame)     }      ... } 

this causes compile error when creating annotation view object:

extra argument 'reuseidentifier' in call

hmm, if implement (required) initializer initwithframe:, loses default initializer initwithannotation:reuseidentifier:?

maybe if added override of initwithannotation:reuseidentifier: calls super available again, work?

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)     }      ... } 

nope, still not - compile error:

property 'self.innercircle' not initialized @ super.init call

ok, if had initwithframe:, initialized subviews in initwithannotation:reuseidentifier:? (but if calls initwithframe: directly?...)

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)     }      ... } 

not surprisingly, swift protects me telling me:

property 'self.innercircle' not initialized @ super.init call

(this time in initwithframe:).

so supposed do? can't create subviews both here , 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) {         innercircle = ...         outercircle = ...          super.init(frame: frame)     }      ... } 

wrong again, works - though i'm assigning constant property twice in same object (!).

does have idea how should done properly?

(note: class included required initwithcoder: initializer calls fatalerror first example, object never created storyboard.)

unfortunately mkannotationview forces implement init(frame: cgrect) means have initialise instance variables in method well.

this article explains bit more

for variables can initialised passed in values have make variables optional , set them nil in init(frame: cgrect).

the reason suspect mkannotationview calling self.initwithframe: rect in objective-c init method. if subclass overrides initwithframe:(cgrect) rect called. however, causes problem in swift because if declare custom designated initialiser not inherit initialisers of superclass. therefore have implement init(frame: cgrect) in subclass.

i have had same problem uitableveiwcontroller. header looks follow same pattern. i.e 2 faliable designated initialisers.

it makes me sad. can do.