[RESOLVED] Get object position during animation

[Kezmondo]

Hi,

I have used Expression Blend to create a very simple animation where an image moves across the screen.

In code (c#), I have a DispatcherTimer which puts the image co-ordinates in a TextBlock with each tick using MyImage.GetValue(Canvas.LeftProperty).

My problem is that the co-ordinates being read never change, they are always the start position, even though I can see the image moving across the screen. If I don't use the storyboard, and instead move the image using MyImage.SetValue(Canvas.LeftProperty, newXpos) then the co-ordinates DO update correctly. It seems that the storyboard method does not update the Canvas.LeftProperty and Canvas.TopProperty values.

Am I missing something here? I want to be able to read the position of an object during an animation, for things like collision detection.

Thanks!


The XAML:

<UserControl
	xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
	xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
	x:Class="AnimateTest.Page"
	Width="640" Height="480">
	<UserControl.Resources>
		<Storyboard x:Name="MoveDuck">
			<DoubleAnimationUsingKeyFrames Storyboard.TargetName="Donald" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[3].(TranslateTransform.X)" BeginTime="00:00:00">
				<SplineDoubleKeyFrame KeyTime="00:00:02" Value="608"/>
			</DoubleAnimationUsingKeyFrames>
			<DoubleAnimationUsingKeyFrames Storyboard.TargetName="Donald" Storyboard.TargetProperty="(UIElement.RenderTransform).(TransformGroup.Children)[3].(TranslateTransform.Y)" BeginTime="00:00:00">
				<SplineDoubleKeyFrame KeyTime="00:00:02" Value="448"/>
			</DoubleAnimationUsingKeyFrames>
			<ColorAnimationUsingKeyFrames Storyboard.TargetName="LayoutRoot" Storyboard.TargetProperty="(Panel.Background).(GradientBrush.GradientStops)[1].(GradientStop.Color)" BeginTime="00:00:00">
				<SplineColorKeyFrame KeyTime="00:00:02" Value="#FFF24D4D"/>
			</ColorAnimationUsingKeyFrames>
			<ColorAnimationUsingKeyFrames Storyboard.TargetName="LayoutRoot" Storyboard.TargetProperty="(Panel.Background).(GradientBrush.GradientStops)[0].(GradientStop.Color)" BeginTime="00:00:00">
				<SplineColorKeyFrame KeyTime="00:00:02" Value="#FF5F5D5D"/>
			</ColorAnimationUsingKeyFrames>
		</Storyboard>
	</UserControl.Resources>

	<Canvas x:Name="LayoutRoot">
		<Canvas.Background>
			<LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
				<GradientStop Color="#FF000000"/>
				<GradientStop Color="#FFFFFFFF" Offset="1"/>
			</LinearGradientBrush>
		</Canvas.Background>
		<Image Source="duck.JPG" Canvas.Top="50" Canvas.Left="50" RenderTransformOrigin="0.5,0.5" x:Name="Donald">
			<Image.RenderTransform>
				<TransformGroup>
					<ScaleTransform/>
					<SkewTransform/>
					<RotateTransform/>
					<TranslateTransform/>
				</TransformGroup>
			</Image.RenderTransform>
		</Image>
		<TextBlock Height="13" Width="65" Canvas.Left="20" Canvas.Top="378" Text="TextBlock" TextWrapping="Wrap" x:Name="txtPos"/>
	</Canvas>
</UserControl>