Come animare l'opacità di un DropShadowEffect?
-
07-07-2019 - |
Domanda
Ho un progetto WPF con un bordo usando il seguente stile. Il piano è di far sbiadire l'effetto bagliore quando il mouse si sposta oltre il bordo e svanire quando esce.
<Style x:Key="BorderGlow" TargetType="Border">
<Style.Resources>
<Storyboard x:Key="GlowOn">
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetProperty="(DropShadowEffect.Opacity)">
<SplineDoubleKeyFrame KeyTime="0:0:0.3" Value="1"/>
</DoubleAnimationUsingKeyFrames>
</Storyboard>
<Storyboard x:Key="GlowOff">
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Storyboard.TargetProperty="(DropShadowEffect.Opacity)">
<SplineDoubleKeyFrame KeyTime="0:0:0.3" Value="0"/>
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</Style.Resources>
<Setter Property="CornerRadius" Value="6,1,6,1" />
<Setter Property="BorderBrush" Value="{StaticResource SelectedBorder}" />
<Setter Property="BorderThickness" Value="1" />
<Setter Property="Background" Value="{StaticResource DeselectedBackground}" />
<Setter Property="RenderTransformOrigin" Value="0.5,0.5" />
<Setter Property="TextBlock.Foreground" Value="{StaticResource SelectedForeground}" />
<Setter Property="RenderTransform">
<Setter.Value>
<RotateTransform Angle="90"/>
</Setter.Value>
</Setter>
<Setter Property="Effect">
<Setter.Value>
<DropShadowEffect ShadowDepth="0" BlurRadius="8" Color="#FFB0E9EF"/>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Trigger.EnterActions>
<BeginStoryboard Storyboard="{StaticResource GlowOn}"/>
</Trigger.EnterActions>
<Trigger.ExitActions>
<BeginStoryboard Storyboard="{StaticResource GlowOff}"/>
</Trigger.ExitActions>
</Trigger>
</Style.Triggers>
</Style>
Il problema è che non succede nulla! L'animazione funziona se cambio " DropShadowEffect " a "UIElement" nella Storyboard TargetProperty, ma questo svanisce l'intero controllo.
Come posso sfumare solo DropShadowEffect? ??
Soluzione
Un paio di punti da notare
1) Devi scegliere come target una proprietà effettiva di Border: stai effettivamente cercando di scegliere come target il valore (DropShadowEffect) della proprietà Effect, non la proprietà stessa.
2) Devi ordinare la sintassi del PropertyPath .
Cambia la proprietà Storyboard.Target in quanto segue e dovresti andare bene:
Storyboard.TargetProperty="(Effect).Opacity"
MODIFICA Codice di lavoro come indicato nel commento:
<Border BorderThickness="10" Height="100" Width="100">
<Border.BorderBrush>
<SolidColorBrush Color="Red"></SolidColorBrush>
</Border.BorderBrush>
<Border.Style>
<Style TargetType="Border">
<Style.Resources>
<Storyboard x:Key="GlowOn">
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00"
Storyboard.TargetProperty="(Effect).Opacity">
<SplineDoubleKeyFrame KeyTime="0:0:0.3" Value="1"/>
</DoubleAnimationUsingKeyFrames>
</Storyboard>
<Storyboard x:Key="GlowOff">
<DoubleAnimationUsingKeyFrames BeginTime="00:00:00"
Storyboard.TargetProperty="(Effect).Opacity">
<SplineDoubleKeyFrame KeyTime="0:0:0.3" Value="0"/>
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</Style.Resources>
<Setter Property="CornerRadius" Value="6,1,6,1" />
<!--<Setter Property="BorderBrush"
Value="{StaticResource SelectedBorder}" />-->
<Setter Property="BorderThickness" Value="1" />
<!--<Setter Property="Background"
Value="{StaticResource DeselectedBackground}" />-->
<Setter Property="RenderTransformOrigin" Value="0.5,0.5" />
<!--<Setter Property="TextBlock.Foreground"
Value="{StaticResource SelectedForeground}" />-->
<Setter Property="RenderTransform">
<Setter.Value>
<RotateTransform Angle="90"/>
</Setter.Value>
</Setter>
<Setter Property="Effect">
<Setter.Value>
<DropShadowEffect ShadowDepth="20"
BlurRadius="8"
Color="#FFB0E9EF"/>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Trigger.EnterActions>
<BeginStoryboard
Storyboard="{StaticResource GlowOn}"/>
</Trigger.EnterActions>
<Trigger.ExitActions>
<BeginStoryboard
Storyboard="{StaticResource GlowOff}"/>
</Trigger.ExitActions>
</Trigger>
</Style.Triggers>
</Style>
</Border.Style>
</Border>