I have the next code in XAML :

   
<Grid.RowDefinitions>
       
<RowDefinition Height="6*" />
       
<RowDefinition Height="*" />
   
</Grid.RowDefinitions>

What I want is to modify the code in C#. I'm using the next code :

 ListBoxGrid.RowDefinitions[0].Height = new GridLength(100);
 ListBoxGrid.RowDefinitions[1].Height = new GridLength(800);

Using pixels to set the Height of the rows works just fine, but I would very much like to use the "*"-thing, something like

 ListBoxGrid.RowDefinitions[0].Height = "*";
 ListBoxGrid.RowDefinitions[1].Height = "3*";

How can I do something like that ? I'm thinking that a solution would be to get the Height of the control/page that contains my grid and make :

 ListBoxGrid.RowDefinitions[0].Height =ControlHeight/4;
 ListBoxGrid.RowDefinitions[1].Height =ControlHeight/4*3;

Is there another solution ? More elegant than these operations ? (I will use more than two rows, so it would be nice to not have something very complicated).