Question

I am trying to animate an error message popup to expand itself slightly then contract to its original size all in about a half second interval to give emphasis to it in WPF. The window is designed as a border with another border inside that houses a stack panel with an icon on the left and a messagebox to the right. On initialization the messagebox gets the exception populated and the whole window’s size is set to sizetocontent. By the way I am using .NET 3.5. Please help!

Answer 1

Add this to your xaml within the outside Border or to the Window

<Style>
  <Setter Property="Border.RenderTransform">
   <Setter.Value>
     <ScaleTransform CenterX="50" CenterY="50" ScaleX="1" ScaleY="1" />
   </Setter.Value>
  </Setter>
<Style.Triggers>
  <EventTrigger RoutedEvent="Border.Loaded">
    <EventTrigger.Actions>
      <BeginStoryboard >
        <Storyboard>
          <DoubleAnimation Duration="0:0:0.5" 
                           Storyboard.TargetProperty="RenderTransform.ScaleX" 
                           From="1.0" To="1.1" Duration="0:0:0.5" 
                           AutoReverse="True"/>
          <DoubleAnimation Duration="0:0:0.5" 
                           Storyboard.TargetProperty="RenderTransform.ScaleY" 
                           From="1.0" To="1.1" Duration="0:0:0.5" 
                           AutoReverse="True"/>
        </Storyboard>
      </BeginStoryboard>
    </EventTrigger.Actions>
  </EventTrigger>
</Style.Triggers>
</Style>