public ActionSheetDelegate (CameraDemoController controller)
 {
     _controller = controller;
 }
 public ActionSheetDelegate(CameraDemoController controller)
 {
     _controller = controller;
 }
 public PickerDelegate (CameraDemoController controller)
 {
     _controller = controller;
 }
 public PickerDelegate(CameraDemoController controller)
 {
     _controller = controller;
 }