注释视图不'；t显示自定义图像-iOS9

我的viewForAnnotation在iOS8中运行良好，但在iOS9中不显示自定义pin图像。图像的路径正常。
怎么了？谢谢大家!

func mapView(mapView: MKMapView, viewForAnnotation annotation: MKAnnotation) -> MKAnnotationView? {
    if annotation is MKUserLocation {
        return nil //return nil so map view draws "blue dot" for standard user location
    }

    let reuseId = "pin"
    var pinView = mapView.dequeueReusableAnnotationViewWithIdentifier(reuseId)

    if pinView == nil {
        pinView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: reuseId)
        pinView!.canShowCallout = true

    }else{
        pinView!.annotation = annotation
    }
    if annotation is MyAnnotation {
        let myPin = annotation as! MyAnnotation

        // Custom image in bubble
        let viewLeftAccessory = UIView(frame: CGRectMake(0, 0, pinView!.frame.size.height + 20, pinView!.frame.size.height + 20))
        let temp = UIImageView(frame: viewLeftAccessory.frame)
        temp.image = UIImage(named: myPin.iconName)
        viewLeftAccessory.addSubview(temp)
        pinView!.leftCalloutAccessoryView = viewLeftAccessory

        pinView!.image = UIImage(named: "BluePin")
        pinView!.rightCalloutAccessoryView = UIButton(type: UIButtonType.DetailDisclosure) as UIView

        return pinView
    }
    return nil
}

改变

到

pinView = MKPinAnnotationView(annotation: annotation, reuseIdentifier: reuseId)

pinView = MKAnnotationView(annotation: annotation, reuseIdentifier: reuseId)