Growing UserControl Size with Style Trigger?
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I would like to cause a custom UserControl to grow by a multiplier when an "IsSelected" DP is set to true.  My current XAML looks like this:

    <ctrl:MyBaseControl x:Class="MyDemo.Controls.MyCustomControl"
             ...>
    <ctrl:MyBaseControl.Resources>
        <Style TargetType="{x:Type ctrl:MyCustomControl}">
            <Setter Property="BorderBrush" Value="White" />
            <Style.Triggers>
                <Trigger Property="IsSelected" Value="True">
                    <Setter Property="BorderThickness" Value="2" />
                    <Setter Property="Width" Value="340" />
                    <Setter Property="Height" Value="260" />
                </Trigger>
            </Style.Triggers>
        </Style>
    </ctrl:MyBaseControl.Resources>
    <Border>
        <StackPanel>
            ...
        </StackPanel>
    </Border>
</ctrl:MyBaseControl>

In the above sample, "MyBaseControl" extends UserControl, and defines the IsSelected DP.

This code just plain isn't working at the moment, which is one of my issues.  The other is that I would like to grow the Width/Height for a certain amount (for example: 0.10) instead of setting it to a hard number.  This way I can set the size when I define the control at the source.

Thanks for any help!