How to make a WPF window be on top of all other windows of my app (not system wide)?

Question

I want my window to be on top of all other windows in my application only. If I set the TopMost property of a window, it becomes on top of all windows of al

Answer 1

I ran into a very similar situation as you. Most of the searches I came across stated all I needed to do was set the Owner of the windows I wish to be Topmost to the main window or whatever window that called Show.

Anyways, I'll go ahead and post a solution that worked well for me.

I created event handlers for Window.Activated and Window.Deactived in the window that was supposed to be Topmost with respect to my application.

private void Window_Activated(object sender, EventArgs e)
{
    Topmost = true;
}

private void Window_Deactived(object sender, EventArgs e)
{
    if(Owner == null || Owner.IsActive)
        return;
    bool hasActiveWindow = false;
    foreach(Window ownedWindow in Owner.OwnedWindows)
    {
        if(ownedWindow.IsActive)
            hasActiveWindow = true; 
    }

    if(!hasActiveWindow)
        Topmost = false;
}

It works great for me. Hopefully this is useful to someone else out there. :o)