i've created usercontrol with viewbox as a main container. If i add this usercontrol to a window it will place all area of it. How to set up default width and height for the control?
<UserControl>
...
<Viewbox>
<Grid Height="167" Width="178">
<ed:RegularPolygon Fill="#FFF4F4F5" InnerRadius="1" PointCount="3" Stroke="Black" RenderTransformOrigin="0.5,0.5" Margin="-39,52,69,52" >
<ed:RegularPolygon.RenderTransform>
<TransformGroup>
<ScaleTransform/>
<SkewTransform/>
<RotateTransform Angle="90"/>
<TranslateTransform/>
</TransformGroup>
</ed:RegularPolygon.RenderTransform>
</ed:RegularPolygon>
</Grid>
</Viewbox>
</UserControl>