c# - 如何从 Xamarin Forms 自定义渲染器中的 View 访问方法？

Question

我有以下代码:

public partial class PhrasesFrameRendererClass : Frame
{
    .....
    void getRandomWords() {
       // more code here that involves getting random numbers 
       // and updating a grid's bindingcontext
    }
}

在我的自定义渲染器中，我希望能够在向左滑动手势时调用 getRandomWords，如下所示:

public class PhraseFrameCustomRenderer : FrameRenderer
{
   UISwipeGestureRecognizer leftSwipeGestureRecognizer;
   protected override void OnElementChanged(ElementChangedEventArgs<Frame> e)
   {
       base.OnElementChanged(e);
       leftSwipeGestureRecognizer = new UISwipeGestureRecognizer();
       leftSwipeGestureRecognizer.Direction = UISwipeGestureRecognizerDirection.Left;
       leftSwipeGestureRecognizer.NumberOfTouchesRequired = 1;
       leftSwipeGestureRecognizer.AddTarget((obj) =>
       {
          // Call getRandomWords() here
       });
   }
}

这可能吗？关于如何做到这一点有什么想法吗？

Answer 1

 base.OnElementChanged(e);
   leftSwipeGestureRecognizer = new UISwipeGestureRecognizer();
   leftSwipeGestureRecognizer.Direction = UISwipeGestureRecognizerDirection.Left;
   leftSwipeGestureRecognizer.NumberOfTouchesRequired = 1;
   leftSwipeGestureRecognizer.AddTarget((obj) =>
   {
      // Call getRandomWords() here
      var frame = Element as PhrasesFrameRendererClass ;
      if(frame!=null){
           frame.getRandomWords();
      }
   });