Swift：如何啓用和禁用地圖視圖上的註釋？

Question

我有一個代碼在地圖視圖上顯示一些註釋。但是，我試圖在用戶點擊UISwitch按鈕時可以啓用或禁用某些功能。有關我如何實現這一目標的任何建議？提前致謝！

let theHouse = MKPointAnnotation() 
     theHouse.coordinate = CLLocationCoordinate2D(latitude: 38.8977, longitude: -77.0365) 

    theHouse.title = "The House, DC" 
     theHouse.subtitle = "New Jersey, DC" 

    myMapView.addAnnotation(theHouse) 
    myAnnotations.append(theHouse.title!) 

    //Switch that toggles the annotation... 
    @IBAction func turnOffAnnotations(_ sender: UISwitch) { 
    //Code that enables and disables the annotation? 

if toggle.isOn{ 
    let visible = myMapView.visibleMapRect 
    let inRect = myMapView.annotations(in: visible) 

    for annotation: MKAnnotation in myMapView.annotations{ 
     if (inRect.contains(anno as! AnyHashable)){ 
      myMapView.removeAnnotation(annotation) 
     } 
    } 
    } else { 
     let visible = myMapView.visibleMapRect 
     let inRect = myMapView.annotations(in: visible) 

     for annotation: MKAnnotation in myMapView.annotations{ 
      if (inRect.contains(anno as! AnyHashable)){ 
       myMapView.addAnnotation(annotation) 
      } 
     } 
    } 
//How to add back the removed annotations here?... 
    } 

Answer 1

使用viewFor(annotation : MKAnnotation)方法：

斯威夫特3

@IBAction func changeAnnotationsVisibility(_ sender: UISwitch) { 
    let annotationVisible = sender.isOn 

    for annotation in myMapView.annotations { 
     myMapView.view(for: annotation)?.isHidden = !annotationVisible 
    } 
}