private void InsertShade(int insertIndex, Shade shade)
{
shade.PropertyChanged -= ShadePropertyChanged;
InternalLogger.Debug(LogTag, () => $"InsertShade( insertIndex: {insertIndex}, shade: {shade} )");
// https://docs.microsoft.com/en-US/windows/uwp/composition/using-the-visual-layer-with-xaml
var ttv = _shadowSource.TransformToVisual(_shadowsCanvas);
Windows.Foundation.Point offset = ttv.TransformPoint(new Windows.Foundation.Point(0, 0));
double width = _shadowSource.ActualWidth;
double height = _shadowSource.ActualHeight;
var shadowHost = new Rectangle()
{
Fill = Xamarin.Forms.Color.White.ToBrush(),
Width = width,
Height = height,
RadiusX = _cornerRadius,
RadiusY = _cornerRadius,
};
Canvas.SetLeft(shadowHost, offset.X);
Canvas.SetTop(shadowHost, offset.Y);
_shadowsCanvas.Children.Insert(insertIndex, shadowHost);
if (_compositor == null)
{
Visual hostVisual = ElementCompositionPreview.GetElementVisual(_shadowsCanvas);
_compositor = hostVisual.Compositor;
}
var dropShadow = _compositor.CreateDropShadow();
dropShadow.BlurRadius = (float)shade.BlurRadius * 2;
dropShadow.Opacity = (float)shade.Opacity;
dropShadow.Color = shade.Color.ToWindowsColor();
dropShadow.Offset = new Vector3((float)shade.Offset.X - SafeMargin, (float)shade.Offset.Y - SafeMargin, 0);
dropShadow.Mask = shadowHost.GetAlphaMask();
var shadowVisual = _compositor.CreateSpriteVisual();
shadowVisual.Size = new Vector2((float)width, (float)height);
shadowVisual.Shadow = dropShadow;
_shadowVisuals.Insert(insertIndex, shadowVisual);
ElementCompositionPreview.SetElementChildVisual(shadowHost, shadowVisual);
shade.PropertyChanged += ShadePropertyChanged;
}
private void UpdateShadow(PancakeView pancake)
{
//For now gets the shadow only when the CornerRadius has the same value for all sides.
if (Control != null && pancake.Shadow != null && pancake.Width > 0 && pancake.Height > 0 &&
pancake.CornerRadius.TopLeft == pancake.CornerRadius.BottomRight &&
pancake.CornerRadius.TopLeft == pancake.CornerRadius.BottomLeft &&
pancake.CornerRadius.BottomRight == pancake.CornerRadius.TopRight)
{
rectangle.Fill = new Windows.UI.Xaml.Media.SolidColorBrush(Windows.UI.Colors.Black);
rectangle.Width = pancake.Width;
rectangle.Height = pancake.Height;
rectangle.RadiusX = pancake.CornerRadius.TopRight + 5;
rectangle.RadiusY = pancake.CornerRadius.TopRight + 5;
var compositor = ElementCompositionPreview.GetElementVisual(rectangle).Compositor;
visual = compositor.CreateSpriteVisual();
visual.Size = new Vector2((float)pancake.Width, (float)pancake.Height);
var shadow = compositor.CreateDropShadow();
shadow.BlurRadius = pancake.Shadow.BlurRadius;
shadow.Mask = rectangle.GetAlphaMask();
shadow.Opacity = pancake.Shadow.Opacity;
shadow.Color = pancake.Shadow.Color.ToWindowsColor();
shadow.Offset = new Vector3((float)pancake.Shadow.Offset.X, (float)pancake.Shadow.Offset.Y, 0);
visual.Shadow = shadow;
ElementCompositionPreview.SetElementChildVisual(rectangle, visual);
}
else
{
if (rectangle != null)
{
rectangle.Fill = new Windows.UI.Xaml.Media.SolidColorBrush(Windows.UI.Colors.Transparent);
}
if (visual != null)
{
visual.Shadow = null;
ElementCompositionPreview.SetElementChildVisual(rectangle, null);
}
}
}
