How to handle Multi-Touch events with SkiaSharp? Xamarin - xamarin

Question

Skiasharp enables to manipulate touch events with the method:
private void OnTouch(object sender, SKTouchEventArgs args)
With this method I can handle only one touch point coordinates:
args.Location.X, args.Location.Y
But how can I detect multitouch event?
The Android native API for example enables you to manage two finger locations in order to detect multitouch.
How can I achieve that with SkiaSharp?

Answer 1

Ok, I found a solution for my question here is the code.
//Multitouch handling
Dictionary<long, SKPoint> dragDictionary = new Dictionary<long, SKPoint>();
private void OnTouch(object sender, SKTouchEventArgs e)
{
switch (e.ActionType)
{
case SKTouchAction.Pressed:
dragDictionary[e.Id] = e.Location;
break;
case SKTouchAction.Entered:
break;
case SKTouchAction.Moved:
if (dragDictionary.Keys.Count > 1)
{
dragDictionary[e.Id] = e.Location;
SKPoint? p1 = null;
SKPoint? p2 = null;
foreach (long key in dragDictionary.Keys)
{
if (p1 == null)
{
p1 = dragDictionary[key];
}
else if (p2 == null)
{
p2 = dragDictionary[key];
}
}
//MultiTouch handle
}
else
{
//SingleTouch handle
}
break;
case SKTouchAction.Released:
dragDictionary.Remove(e.Id);
break;
case SKTouchAction.Exited:
break;
}
// we have handled these events
e.Handled = true;
((SKCanvasView)sender).InvalidateSurface();
}