StartListenPointer Sample

StartListenPointer.cs

private void StartListenPointer()
{
  var pointerPressed = Observable.FromEvent<PointerEventHandler, PointerRoutedEventArgs>(
      h => (sender, e) => h(e),
      h => AssociatedSelector.PointerPressed += h,
      h => AssociatedSelector.PointerPressed -= h)
    .Where(e => e.Pointer.PointerDeviceType == PointerDeviceType.Mouse);

  var pointerMoved = Observable.FromEvent<PointerEventHandler, PointerRoutedEventArgs>(
      h => (sender, e) => h(e),
      h => AssociatedSelector.PointerMoved += h,
      h => AssociatedSelector.PointerMoved -= h);

  var pointerUnpressed = Observable.Merge(
    Observable.FromEvent<PointerEventHandler, PointerRoutedEventArgs>(
      h => (sender, e) => h(e),
      h => AssociatedSelector.PointerReleased += h,
      h => AssociatedSelector.PointerReleased -= h),
    Observable.FromEvent<PointerEventHandler, PointerRoutedEventArgs>(
      h => (sender, e) => h(e),
      h => AssociatedSelector.PointerCanceled += h,
      h => AssociatedSelector.PointerCanceled -= h),
    Observable.FromEvent<PointerEventHandler, PointerRoutedEventArgs>(
      h => (sender, e) => h(e),
      h => AssociatedSelector.PointerCaptureLost += h,
      h => AssociatedSelector.PointerCaptureLost -= h));

  disposer.Add(pointerMoved
    .SkipUntil(pointerPressed.Do(e => OnPointerPressed(e)))
    .TakeUntil(pointerUnpressed.Do(e => OnPointerUnpressed(e)))
    .Throttle(TimeSpan.FromMilliseconds(10)) // 10 msec throttling
    .ObserveOn(SynchronizationContext.Current)
    .Repeat()
    .Subscribe(e => OnPointerMoved(e)));
}