Use this :
//Define your function like this
func initWithAnnotation(annotation:MKAnnotation, reuseIdentifier:String, completion: ()->Void) {
//Your implementation goes here
//for call back
completion()
}
//call above function by this:
self.initWithAnnotation(Your_MKProtocol, reuseIdentifier: "identifier", completion: {
//Your call back implementations
//Similar to delegate callback
})
solved How to write following method in swift? [closed]