Reputation: 23
Using a DoubleAnimation, the attached property Canvas.Left should be gradually set to 100:
<Ellipse Width="30" Height="30" Fill="Purple">
<Ellipse.Triggers>
<EventTrigger RoutedEvent="Ellipse.Loaded">
<BeginStoryboard>
<Storyboard>
<DoubleAnimation Duration="0:0:5" Storyboard.TargetProperty="(Canvas.Left)" To="100" RepeatBehavior="Forever" />
</Storyboard>
</BeginStoryboard>
</EventTrigger>
</Ellipse.Triggers>
</Ellipse>
This Ellipse (part of a datatemplate for my viewmodel) is binded to the ItemsControl through ItemsSource:
<ItemsControl ItemsSource="{Binding Components}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<Canvas Background="Beige" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemContainerStyle>
<Style TargetType="ContentPresenter">
<Setter Property="Canvas.Left" Value="{Binding X}" />
<Setter Property="Canvas.Top" Value="{Binding Y}" />
</Style>
</ItemsControl.ItemContainerStyle>
</ItemsControl>
However, when the ellipse is loaded, the following exception occurs:
Cannot animate the 'Left' property on a 'System.Windows.Shapes.Ellipse' using a 'System.Windows.Media.Animation.DoubleAnimation'.
But the targetproperty of the animation is specified as "Canvas.Left" and not "Left"?
Upvotes: 2
Views: 3244
Reputation: 20820
You need to initialize Canvas.Left for the DoubleAnimation to work:
<Ellipse Width="30" Height="30" Fill="Purple" Canvas.Left="0">
Upvotes: 1