Android

I have an rotated textview and I want to drag and drop this view.
The problem is that the drag shadow has no rotation.

I found a solution for android in java but this does not work for me. 
Maybe I translate the code wrong 

<a href="https://stackoverflow.com/questions/17049938/how-to-drag-a-rotated-dragshadow"></a>[<a href="https://stackoverflow.com/questions/17049938/how-to-drag-a-rotated-dragshadow" target="_blank" title="New Window">^</a>]

        class CustomDragShdowBuilder : View.DragShadowBuilder
            {
                private View _view;
                public CustomDragShdowBuilder(View view)
                {
                    _view = view;
                }
        
        
                public override void OnDrawShadow(Canvas canvas)
                {
                    double rotationRad = Math.ToRadians(_view.Rotation);
                    int w = (int)(_view.Width * _view.ScaleX);
                    int h = (int)(_view.Height * _view.ScaleY);
                    double s = Math.Abs(Math.Sin(rotationRad));
                    double c = Math.Abs(Math.Cos(rotationRad));
        
                    int width = (int)(w * c + h * s);
                    int height = (int)(w * s + h * c);
        
                    canvas.Scale(_view.ScaleX, _view.ScaleY, width / 2, height / 2);
                    canvas.Rotate(_view.Rotation, width / 2, height / 2);
                    canvas.Translate((width - _view.Width) / 2, (height - _view.Height) / 2);
        
                    base.OnDrawShadow(canvas);
                }
        
                public override void OnProvideShadowMetrics(Point shadowSize, Point shadowTouchPoint)
                {
                    shadowTouchPoint.Set(shadowSize.X / 2, shadowSize.Y / 2);
                    base.OnProvideShadowMetrics(shadowSize, shadowTouchPoint);
                }