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c#.netwpfuser32taskbar

Flashing Window not working for TabbedThumbnail (custom taskbar preview)

For my application I'm using the FlashWindowEx(ref FLASHWINFO pwfi) form the user32.dll to flash the taskbar and my window for attention.

At this moment I am trying to add a custom image for the preview of the window in the taskbar, best way I found is by using the TaskbarManager in the WindowsAPICodePack.

This works alright, but when I call the method to flash the window, the taskbar is flashing but the Window wich is represented by a TabbedThumbnail is not.

Sample of a program that is using this is Skype for Business (former Lync). To make more clear what is happening and what I would like to have, I added a image and a demo project.

image problem:

image problem

Is there a way to get both of these features together, like skype for business is doing?

image s4b:

image s4b

Source for demo project: http://project14.net/Dev/csharp/FlashingCustomTaskbarItem.zip

Thanks for you time!

Solution

  • I found an answer myself. I downloaded the WindowsAPICodePack and extended the GlassWindow. It took a while to get everything right in WPF.

    Here is a sample for winForms: http://www.codeproject.com/Articles/45567/Creating-a-Timer-Using-the-Amazing-New-Windows-F

    Interceptiinbg the windows messages can be done by adding a hook to the HwndSource.

    protected override void OnSourceInitialized(EventArgs e)
{
    base.OnSourceInitialized(e);
    HwndSource source = PresentationSource.FromVisual(this) as HwndSource;
    source.AddHook(WndProc);
}

private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, 

ref bool handled)
{
    if(msg == (int)TaskbarNativeMethods.WM_DWMSENDICONICLIVEPREVIEWBITMAP)
    {
        // get your bitmap an SetIconicThumbnail...
    }
}

    Still trying to improve my code with some better features now.