Question

In a Silverlight app, I’d like my buttons to enlarge by a few pixels when the mouse is hovering over them. I’d also like it to animate to the new size, rather than just suddenly becoming larger. How can I accomplish this in XAML?

Answer 1

Create a ControlTemplate for your button with a storyboard to animate height/width or transform properties, and a trigger to fire the storyboard on MouseEnter event.

Something a bit like this should do the trick.

here is some code…. its a bit lengthy and it uses VisualStates….

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    x:Class="SilverlightApplication1.MainPage"
    Width="640" Height="480">
    <UserControl.Resources>
        <Style x:Key="ButtonStyle1" TargetType="Button">
            <Setter Property="Background" Value="#FF1F3B53"/>
            <Setter Property="Foreground" Value="#FF000000"/>
            <Setter Property="Padding" Value="3"/>
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="BorderBrush">
                <Setter.Value>
                    <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                        <GradientStop Color="#FFA3AEB9" Offset="0"/>
                        <GradientStop Color="#FF8399A9" Offset="0.375"/>
                        <GradientStop Color="#FF718597" Offset="0.375"/>
                        <GradientStop Color="#FF617584" Offset="1"/>
                    </LinearGradientBrush>
                </Setter.Value>
            </Setter>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="Button">
                        <Grid x:Name="grid" RenderTransformOrigin="0.5,0.5">
                            <Grid.RenderTransform>
                                <TransformGroup>
                                    <ScaleTransform/>
                                    <SkewTransform/>
                                    <RotateTransform/>
                                    <TranslateTransform/>
                                </TransformGroup>
                            </Grid.RenderTransform>
                            <VisualStateManager.VisualStateGroups>
                                <VisualStateGroup x:Name="CommonStates">
                                    <VisualState x:Name="Normal"/>
                                    <VisualState x:Name="MouseOver">
                                        <Storyboard>
                                            <DoubleAnimationUsingKeyFrames Storyboard.TargetName="BackgroundAnimation" Storyboard.TargetProperty="Opacity">
                                                <SplineDoubleKeyFrame KeyTime="0" Value="1"/>
                                            </DoubleAnimationUsingKeyFrames>
                                            <ColorAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Rectangle.Fill).(GradientBrush.GradientStops)[1].(GradientStop.Color)">
                                                <SplineColorKeyFrame KeyTime="0" Value="#F2FFFFFF"/>
                                            </ColorAnimationUsingKeyFrames>
                                            <ColorAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Rectangle.Fill).(GradientBrush.GradientStops)[2].(GradientStop.Color)">
                                                <SplineColorKeyFrame KeyTime="0" Value="#CCFFFFFF"/>
                                            </ColorAnimationUsingKeyFrames>
                                            <ColorAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Rectangle.Fill).(GradientBrush.GradientStops)[3].(GradientStop.Color)">
                                                <SplineColorKeyFrame KeyTime="0" Value="#7FFFFFFF"/>
                                            </ColorAnimationUsingKeyFrames>
                                            <DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Duration="00:00:00.0010000" Storyboard.TargetName="grid" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleX)">
                                                <EasingDoubleKeyFrame KeyTime="00:00:00" Value="1.25"/>
                                            </DoubleAnimationUsingKeyFrames>
                                            <DoubleAnimationUsingKeyFrames BeginTime="00:00:00" Duration="00:00:00.0010000" Storyboard.TargetName="grid" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[0].(ScaleTransform.ScaleY)">
                                                <EasingDoubleKeyFrame KeyTime="00:00:00" Value="1.25"/>
                                            </DoubleAnimationUsingKeyFrames>
                                        </Storyboard>
                                    </VisualState>
                                    <VisualState x:Name="Pressed">
                                        <Storyboard>
                                            <ColorAnimationUsingKeyFrames Storyboard.TargetName="Background" Storyboard.TargetProperty="(Border.Background).(SolidColorBrush.Color)">
                                                <SplineColorKeyFrame KeyTime="0" Value="#FF6DBDD1"/>
                                            </ColorAnimationUsingKeyFrames>
                                            <DoubleAnimationUsingKeyFrames Storyboard.TargetName="BackgroundAnimation" Storyboard.TargetProperty="Opacity">
                                                <SplineDoubleKeyFrame KeyTime="0" Value="1"/>
                                            </DoubleAnimationUsingKeyFrames>
                                            <ColorAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Rectangle.Fill).(GradientBrush.GradientStops)[0].(GradientStop.Color)">
                                                <SplineColorKeyFrame KeyTime="0" Value="#D8FFFFFF"/>
                                            </ColorAnimationUsingKeyFrames>
                                            <ColorAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Rectangle.Fill).(GradientBrush.GradientStops)[1].(GradientStop.Color)">
                                                <SplineColorKeyFrame KeyTime="0" Value="#C6FFFFFF"/>
                                            </ColorAnimationUsingKeyFrames>
                                            <ColorAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Rectangle.Fill).(GradientBrush.GradientStops)[2].(GradientStop.Color)">
                                                <SplineColorKeyFrame KeyTime="0" Value="#8CFFFFFF"/>
                                            </ColorAnimationUsingKeyFrames>
                                            <ColorAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGradient" Storyboard.TargetProperty="(Rectangle.Fill).(GradientBrush.GradientStops)[3].(GradientStop.Color)">
                                                <SplineColorKeyFrame KeyTime="0" Value="#3FFFFFFF"/>
                                            </ColorAnimationUsingKeyFrames>
                                        </Storyboard>
                                    </VisualState>
                                    <VisualState x:Name="Disabled">
                                        <Storyboard>
                                            <DoubleAnimationUsingKeyFrames Storyboard.TargetName="DisabledVisualElement" Storyboard.TargetProperty="Opacity">
                                                <SplineDoubleKeyFrame KeyTime="0" Value=".55"/>
                                            </DoubleAnimationUsingKeyFrames>
                                        </Storyboard>
                                    </VisualState>
                                </VisualStateGroup>
                                <VisualStateGroup x:Name="FocusStates">
                                    <VisualState x:Name="Focused">
                                        <Storyboard>
                                            <DoubleAnimationUsingKeyFrames Storyboard.TargetName="FocusVisualElement" Storyboard.TargetProperty="Opacity">
                                                <SplineDoubleKeyFrame KeyTime="0" Value="1"/>
                                            </DoubleAnimationUsingKeyFrames>
                                        </Storyboard>
                                    </VisualState>
                                    <VisualState x:Name="Unfocused"/>
                                </VisualStateGroup>
                            </VisualStateManager.VisualStateGroups>
                            <Border x:Name="Background" Background="White" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="3">
                                <Grid Margin="1" Background="{TemplateBinding Background}">
                                    <Border x:Name="BackgroundAnimation" Opacity="0" Background="#FF448DCA"/>
                                    <Rectangle x:Name="BackgroundGradient">
                                        <Rectangle.Fill>
                                            <LinearGradientBrush EndPoint=".7,1" StartPoint=".7,0">
                                                <GradientStop Color="#FFFFFFFF" Offset="0"/>
                                                <GradientStop Color="#F9FFFFFF" Offset="0.375"/>
                                                <GradientStop Color="#E5FFFFFF" Offset="0.625"/>
                                                <GradientStop Color="#C6FFFFFF" Offset="1"/>
                                            </LinearGradientBrush>
                                        </Rectangle.Fill>
                                    </Rectangle>
                                </Grid>
                            </Border>
                            <ContentPresenter x:Name="contentPresenter" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}" Content="{TemplateBinding Content}" ContentTemplate="{TemplateBinding ContentTemplate}"/>
                            <Rectangle x:Name="DisabledVisualElement" Fill="#FFFFFFFF" RadiusX="3" RadiusY="3" IsHitTestVisible="false" Opacity="0"/>
                            <Rectangle x:Name="FocusVisualElement" Stroke="#FF6DBDD1" StrokeThickness="1" RadiusX="2" RadiusY="2" Margin="1" IsHitTestVisible="false" Opacity="0"/>
                        </Grid>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>
    </UserControl.Resources>

    <Grid x:Name="LayoutRoot" Background="White">
        <Button HorizontalAlignment="Center" VerticalAlignment="Center" Width="75" Content="Button" Style="{StaticResource ButtonStyle1}"/>
    </Grid>
</UserControl>