Animating Grid Column or Grid Row in XAML?

Question

Is there any way I can animate Grid column width or Grid row height from XAML?

Answer 1

How about a work around? Why not place a grid(or any other desired control) inside the particular row that you want to animate, set the row height to "Auto", then animate the height of the control. It worked for me.

<Grid>
  <Grid.RowDefinitions>
    <RowDefinition Height="30"/>
    <RowDefinition Height="Auto"/>
  </Grid.RowDefinitions>
  <Button x:Name="ExpandCollapseBtn" Width="100" Click="ExpandCollapse_Click"/>
  <WrapPanel x:Name="ToolBox" Grid.Row="1" Height="0">
    <Button Content="1" Width="50" Height="50"/>
    <Button Content="2" Width="50" Height="50"/>
    <Button Content="3" Width="50" Height="50"/>
    <Button Content="4" Width="50" Height="50"/>
  </WrapPanel>
</Grid>

Code behind:

private bool Expanded = false;
void ExpandCollapse_Click(object sender, RoutedEventArgs e)
{
  if (Expanded)
  {
    var anim = new DoubleAnimation(0, (Duration)TimeSpan.FromSeconds(0.3));
    anim.Completed += (s, _) => Expanded = false;
    ToolBox.BeginAnimation(ContentControl.HeightProperty, anim);
  }
  else
  {
    var anim = new DoubleAnimation(100, (Duration)TimeSpan.FromSeconds(0.3));
    anim.Completed += (s, _) => Expanded = true;
    ToolBox.BeginAnimation(ContentControl.HeightProperty, anim);
  }
}

I admit its not what you are looking for. But its a quick solution(Assuming of course that ultimately you want the UIElement placed inside the grid animated by animating the grid row). You can similarly do it for column width.

Answer 2

The ColumnDefinition.Width and RowDefinition.Height properties are of type GridLength, and there is no built-in animations for this type. So if you want to do that, you will probably have to create your own GridLengthAnimation class. That's probably not too impossible if you take DoubleAnimation as an example, but not easy either...

EDIT: actually, there are several interesting results if you search "GridLength animation" on Google...

http://windowsclient.net/learn/video.aspx?v=70654
http://marlongrech.wordpress.com/2007/08/20/gridlength-animation/
http://www.codeproject.com/KB/WPF/GridLengthAnimation.aspx