How to run storyboard on textblock string is changed in Silverlight? - silverlight

Question

I am wondering if any simple technique to run storyboard if textblock text string was changed. Thank you in advance!

Answer 1

Below is xaml for a user control that will animate the opacity of an item when the Text property of a TextBlock is changed.
It is using a PropertyChangedTrigger and ControlStoryboard action to cause this to happen. These items come from dlls that get installed with Blend, but you can install them separately if you don't have Blend: Blend 4 SDK
<UserControl
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
xmlns:ei="http://schemas.microsoft.com/expression/2010/interactions"
x:Class="TextboxAnimation.MainPage"
Width="640" Height="480">
<UserControl.Resources>
<Storyboard x:Name="AnAnimation">
<DoubleAnimationUsingKeyFrames
Storyboard.TargetProperty="(UIElement.Opacity)"
Storyboard.TargetName="animationTextBlock">
<EasingDoubleKeyFrame KeyTime="0" Value="0"/>
<EasingDoubleKeyFrame KeyTime="0:0:1" Value="1"/>
</DoubleAnimationUsingKeyFrames>
</Storyboard>
</UserControl.Resources>
<StackPanel x:Name="LayoutRoot" Background="White">
<TextBlock x:Name="textBlock"
HorizontalAlignment="Left" Text="Click Me To Change Text"
MouseLeftButtonDown="TextBlockClicked">
<i:Interaction.Triggers>
<ei:PropertyChangedTrigger Binding="{Binding Text, ElementName=textBlock}">
<ei:ControlStoryboardAction Storyboard="{StaticResource AnAnimation}"/>
</ei:PropertyChangedTrigger>
</i:Interaction.Triggers>
</TextBlock>
<TextBlock
x:Name="animationTextBlock"
Text="Animate Me!" Margin="0,8,0,0" Opacity="0"/>
</StackPanel>
</UserControl>
Here is the code behind that is used for the click event, which changes the TextBlock Text property:
int times = 0;
private void TextBlockClicked(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
times++;
textBlock.Text = String.Format("I've been clicked and changed {0} times!", times);
}