Cambio de fondo de WPF de Border OnMouseDown

storyboard eventtrigger

Question

Estoy tratando de cambiar el fondo de un borde en el botón izquierdo del mouse hacia abajo. Botón No lo entiendo Por supuesto, mi gradiente tiene 3 paradas.

Eventtrigger:

<EventTrigger  RoutedEvent="UIElement.PreviewMouseLeftButtonDown" SourceName="border">
    <BeginStoryboard x:Name="MouseDown_BeginStoryboard" Storyboard="{StaticResource OnMouseDown}"/>
</EventTrigger>

StoryBoard:

<Storyboard x:Key="OnMouseDown">
    <ColorAnimation Duration="0:0:0.15" Storyboard.TargetName="border" Storyboard.TargetProperty="Background.GradientStops[0].Color" To="Red" />
    <ColorAnimation Duration="0:0:0.15" Storyboard.TargetName="border" Storyboard.TargetProperty="Background.GradientStops[1].Color" To="Red" />
    <ColorAnimation Duration="0:0:0.15" Storyboard.TargetName="border" Storyboard.TargetProperty="Background.GradientStops[2].Color" To="Red" />
</Storyboard>

Si alguien ve el error, por favor dímelo;)

Answer 1

No veo ningún error obvio y el proyecto de muestra que creé usando el código que publicó funciona bien. Tal vez puedas usarlo para encontrar la fuente de tu problema

<Window.Resources>
    <Storyboard x:Key="OnMouseDown">
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[0].Color"
                        To="Red" />
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[1].Color"
                        To="Red" />
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[2].Color"
                        To="Red" />
    </Storyboard>
</Window.Resources>
<Grid>
    <Border Name="border">
        <Border.Background>
            <LinearGradientBrush>
                <GradientStop Color="Red" Offset="0"/>
                <GradientStop Color="Green" Offset="0.5"/>
                <GradientStop Color="Blue" Offset="1.0"/>
            </LinearGradientBrush>
        </Border.Background>
        <Border.Triggers>
            <EventTrigger RoutedEvent="PreviewMouseLeftButtonDown"
                          SourceName="border">
                <BeginStoryboard x:Name="MouseDown_BeginStoryboard"
                                 Storyboard="{StaticResource OnMouseDown}"/>
            </EventTrigger>
        </Border.Triggers>
    </Border>
</Grid>

Actualizar

Intenté agregar un evento MouseLeave también y sigue funcionando.

Actualización 2

MouseEnter agregado

<Window.Resources>
    <Storyboard x:Key="OnMouseDown">
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[0].Color"
                        To="Red" />
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[1].Color"
                        To="Red" />
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[2].Color"
                        To="Red" />
    </Storyboard>
    <Storyboard x:Key="OnMouseLeave">
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[0].Color"
                        To="Blue" />
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[1].Color"
                        To="Blue" />
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[2].Color"
                        To="Blue" />
    </Storyboard>
    <Storyboard x:Key="OnMouseEnter">
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[0].Color"
                        To="Green" />
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[1].Color"
                        To="Green" />
        <ColorAnimation Duration="0:0:0.15"
                        Storyboard.TargetName="border"
                        Storyboard.TargetProperty="Background.GradientStops[2].Color"
                        To="Green" />
    </Storyboard>
</Window.Resources>
<Grid>
    <Border Name="border">
        <Border.Background>
            <LinearGradientBrush>
                <GradientStop Color="Red" Offset="0"/>
                <GradientStop Color="Green" Offset="0.5"/>
                <GradientStop Color="Blue" Offset="1.0"/>
            </LinearGradientBrush>
        </Border.Background>
        <Border.Triggers>
            <EventTrigger RoutedEvent="PreviewMouseLeftButtonDown" SourceName="border">
                <BeginStoryboard x:Name="MouseDown_BeginStoryboard" Storyboard="{StaticResource OnMouseDown}"/>
            </EventTrigger>
            <EventTrigger RoutedEvent="MouseLeave" SourceName="border">
                <BeginStoryboard x:Name="MouseLeave_BeginStoryboard" Storyboard="{StaticResource OnMouseLeave}"/>
            </EventTrigger>
            <EventTrigger RoutedEvent="MouseEnter" SourceName="border">
                <BeginStoryboard x:Name="MouseEnter_BeginStoryboard" Storyboard="{StaticResource OnMouseEnter}"/>
            </EventTrigger>
        </Border.Triggers>
    </Border>
</Grid>