how to make Image click through?

Question

I wanna display an icon in a window. I want the whole window click through including icon so user can operate other application behind the window as if the window and the icon don't exist. So I create a transparent window and put an Image control on it. Now the window is click through, but user cannot pass mouse click on the icon to the applications behind it. So is it possible to set such an image click through? I have tried to set focusable=false and IsHitTestVisible=false and even set e.Handled = false PreviewMouseLeftButtonDown handler, but no luck.
<Window x:Class="WpfApp1.MainWindow"
........
ShowInTaskbar="True"
BorderBrush="Gray"
Title="WpfAppDemo"
Background="{x:Null}"
AllowsTransparency="True"
WindowStyle="None"
Height="350"
Width="400">
<Border>
<Image Width="24" Height="24" Source="/WpfApp1;component/icon.png"/>
</Border>
</Window>

Answer 1

Hi,@Vincent li . Welcome. Microsoft Q&A.
According to my testing IsHitTestVisible=false works. You could try to refer to the code below.

MainWindow.xaml:

    <Window x:Class="ImageClickThrough.MainWindow"  
....  
            mc:Ignorable="d" ShowInTaskbar="True"  
    BorderBrush="Gray" Background="{x:Null}"  
    AllowsTransparency="True"  
    WindowStyle="None"  
            Title="MainWindow" Height="450" Width="800">  
        <Grid>  
            <TextBlock Text="hello" Foreground="Red" FontSize="20" Height="24" Width="54" PreviewMouseDown="TextBlock_PreviewMouseDown" />  
            <Border>  
                <Image Width="24" Height="24" Source="37.jpg"  IsHitTestVisible="False" MouseLeftButtonDown="Image_MouseDown" />  
            </Border>  
        </Grid>  
    </Window>  

MainWindow.xaml.cs:
275740-clickwindowthrough.txt

The result:

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