LayerVisual 类

定义

public ref class LayerVisual sealed : ContainerVisual

/// [Windows.Foundation.Metadata.ContractVersion(Microsoft.Foundation.LiftedContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
class LayerVisual final : ContainerVisual

/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
/// [Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
/// [Windows.Foundation.Metadata.ContractVersion(Microsoft.Foundation.WindowsAppSDKContract, 65536)]
class LayerVisual final : ContainerVisual

[Windows.Foundation.Metadata.ContractVersion(typeof(Microsoft.Foundation.LiftedContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
public sealed class LayerVisual : ContainerVisual

[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
[Windows.Foundation.Metadata.Threading(Windows.Foundation.Metadata.ThreadingModel.Both)]
[Windows.Foundation.Metadata.ContractVersion(typeof(Microsoft.Foundation.WindowsAppSDKContract), 65536)]
public sealed class LayerVisual : ContainerVisual

Public NotInheritable Class LayerVisual
Inherits ContainerVisual

继承

Object Platform::Object IInspectable CompositionObject Visual ContainerVisual LayerVisual

属性

ContractVersionAttribute MarshalingBehaviorAttribute ThreadingAttribute

示例

将效果应用于 LayerVisual

private async void InitComposition()
{
  Compositor compositor = ElementCompositionPreview.GetElementVisual(MyGrid).Compositor;

  //Create LayerVisual
  LayerVisual layerVisual = compositor.CreateLayerVisual();
  layerVisual.Size = new Vector2(900,900);

  //Create SpriteVisuals to use as LayerVisual child
  SpriteVisual sv1 = compositor.CreateSpriteVisual();
  sv1.Brush = compositor.CreateColorBrush(Windows.UI.Colors.Blue);
  sv1.Size = new Vector2(300, 300);
  sv1.Offset = new Vector3(200, 200, 0);

  SpriteVisual sv2 = compositor.CreateSpriteVisual();
  sv2.Brush = compositor.CreateColorBrush(Colors.Red);
  sv2.Size = new Vector2(300, 300);
  sv2.Offset = new Vector3(400, 400, 0);

  //Add children to the LayerVisual
  layerVisual.Children.InsertAtTop(sv1);
  layerVisual.Children.InsertAtTop(sv2);

  //Create Effect
  var graphicsEffect = new GaussianBlurEffect
  {
     Name = "Blur",
     Source = new CompositionEffectSourceParameter("Backdrop"),
     BlurAmount = 10.0f,
     BorderMode = EffectBorderMode.Hard,
     Optimization = EffectOptimization.Balanced
  };

  var blurEffectFactory = compositor.CreateEffectFactory(graphicsEffect,
      new[] { "Blur.BlurAmount" });
  var blurBrush = blurEffectFactory.CreateBrush();

  //Apply Effect
  layerVisual.Effect = blurBrush;

  ElementCompositionPreview.SetElementChildVisual(MyGrid, layerVisual);
}        

添加 DropShadow

private async void InitComposition()
{
  Compositor compositor = ElementCompositionPreview.GetElementVisual(MyGrid).Compositor;

  //Create LayerVisual
  LayerVisual layerVisual = compositor.CreateLayerVisual();
  layerVisual.Size = new Vector2(900, 900);

  //Create SpriteVisuals to use as LayerVisual child
  SpriteVisual sv1 = compositor.CreateSpriteVisual();
  sv1.Brush = compositor.CreateColorBrush(Windows.UI.Colors.Blue);
  sv1.Size = new Vector2(300, 300);
  sv1.Offset = new Vector3(200, 200, 0);

  SpriteVisual sv2 = compositor.CreateSpriteVisual();
  sv2.Brush = compositor.CreateColorBrush(Colors.Red);
  sv2.Size = new Vector2(300, 300);
  sv2.Offset = new Vector3(400, 400, 0);

  //Add children to the LayerVisual
  layerVisual.Children.InsertAtTop(sv1);
  layerVisual.Children.InsertAtTop(sv2);

  //Create DropShadow
  DropShadow shadow = compositor.CreateDropShadow();
  shadow.Color = Colors.DarkSlateGray;
  shadow.Offset = new Vector3(40, 40, 0);
  shadow.BlurRadius = 9;
  shadow.SourcePolicy = CompositionDropShadowSourcePolicy.InheritFromVisualContent;

  //Associate Shadow with LayerVisual
  layerVisual.Shadow = shadow;

  ElementCompositionPreview.SetElementChildVisual(MyGrid, layerVisual);
}         

注解

LayerVisual 是一种特殊的输入类型，可用于选择视觉对象树。 使用 LayerVisual 隐式指定树输入。 将 EffectBrush 设置为 LayerVisual 的 Effect 属性时，EffectBrush 会自动使用 Root 位于 LayerVisual 的子树作为输入。 LayerVisual 的隐式输入适用于效果，如下所示：

• 如果效果有一个输入，则 EffectBrush 将使用 Root 位于 LayerVisual 的子树作为输入。
• 如果效果有 2 个输入，则 EffectBrush 的第一个无界输入使用 Root 位于 LayerVisual 的子树作为输入。
• 系统不允许将输入为 0 的效果或所有输入都绑定到 SurfaceBrush 的效果设置为 LayerVisual 的 EffectBrush 的 EffectBrush 属性。 这会引发异常。

属性

方法

适用于

另请参阅

• ContainerVisual
• IClosable