opaque element in a transparent in WPF

Question

In my application I'd like to have a transparent window but fully opaque children controls underneath. However, WPF makes all children transparent.

See the XAML below. The grid is semi-transparent 50% as expected but the rectangle in it is trasparent not opaque even thought opacity="1". Is there any way to achieve this?

<Window x:Class="WpfApplication10.Window1"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="Window1" AllowsTransparency="True" Height="300" ResizeMode="NoResize" Width="300" WindowStyle="None" Background="Transparent"  >

    <Border   BorderBrush="black"  BorderThickness="7" CornerRadius="10">
        <Grid Background="Red" Opacity="0.5"     >

        <Rectangle Width="100" Height="100" Fill="white" Opacity="1"/>

    </Grid>
    </Border></Window>

thanks, cellik

Answer 1

The reason why your rectangle is not fully opaque is because your container (the grid) has an opacity of .5, and opacity gets inherited to the child objects.

Instead, try changing the Background Brush of the Grid to something semi-transparent like:

<Grid Background="#66ff0000">

This should give you a semi-transparent Grid and a fully opaque rectangle.