WPF XAML Animation (Newbie)

animation, wpf, xaml

Solution

You need to declare a `Storyboard` and start it upon load:

 <TextBlock x:Name="Text" Text="Hello!!">
            <TextBlock.Triggers>
                <EventTrigger RoutedEvent="FrameworkElement.Loaded">
                    <EventTrigger.Actions>
                        <BeginStoryboard>
                            <Storyboard Duration="00:00:01" RepeatBehavior="Forever" AutoReverse="True">
                                <DoubleAnimation From="10" To="20" Storyboard.TargetName="Text" Storyboard.TargetProperty="FontSize"/>   
                            </Storyboard>                            
                        </BeginStoryboard>
                    </EventTrigger.Actions>
                </EventTrigger>
            </TextBlock.Triggers>
    </TextBlock>

Problem

I am trying to test animation in XAML. My intension was to make a font-size pulse (increase and decrease forever). But when I type in the code below, Visual studio does not recognize the class `DoubleAnimation`. What am I doing wrong? ``` <Window x:Class="testingAnimation.MainWindow" xmlns="http://schemas.microsoft.com/netfx/2007/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="MainWindow" Height="350" Width="525"> <StackPanel> <TextBlock Text="HELLO"> <TextBlock.FontSize> <DoubleAnimation /> </TextBlock.FontSize> </TextBlock> </StackPanel> </Window> ```

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