how to change the height of a grid row in wpf using storyboard

I have a Grid with 2 rows:

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="150"/>
        <RowDefinition />
        <RowDefinition Height="Auto" x:Name="OtherContactsRow" />
    </Grid.RowDefinitions>
    Something here
</Grid>

and 2 Storyboards:

<Storyboard x:Key="MaximizedStoryboard">
    <DoubleAnimation From="20" To="150"  Duration="0:0:2"
                     Storyboard.TargetName="OtherContactsRow"
                     Storyboard.TargetPr开发者_JAVA技巧operty="Height" >    
    </DoubleAnimation>
</Storyboard>

<Storyboard x:Key="MinimizedStoryboard">
    <DoubleAnimation From="150" To="20" Duration="0:0:2"
                     Storyboard.TargetName="OtherContactsRow"
                     Storyboard.TargetProperty="Height">
    </DoubleAnimation>
</Storyboard>

When I try to modify the height of the row named OtherContactsRow I received the following error:

'System.Windows.Media.Animation.DoubleAnimation' animation object cannot be used to animate property 'Height' because it is of incompatible type 'System.Windows.GridLength'.

Any solutions?

You could try the ActualHeight property. It is a double.