I am opening a modal xamDialogWindow in several places in my application (the main window and child windows). By default, when you click the close button, the window only gets hidden. That's no good in this situation, because these windows could be opened and closed lots of times and I don't want to reuse the existing one. So to make sure it's unloaded properly, I am handling the WindowStateChanged event and removing it from the parent grid, like so:

private void XamDialogWindow_WindowStateChanged(object sender, WindowStateChangedEventArgs e)
{
    if (e.NewWindowState == Infragistics.Controls.Interactions.WindowState.Hidden)
    {
        Panel p = VisualTreeHelper.GetParent(this) as Panel;
        if (p != null)
        {
            p.Children.Remove(this);
        }
                
    }
}

I'm not sure if this is the correct way to do it, but on the surface, it appears to work fine.

However, the problem that arises is that your internal DialogManager class holds on to references to the container, and this is only cleaned up in the Unloaded event of the xamDialogWindow. If I've already removed the window from it's parent grid then the cleanup code is unable to work out how to properly clean it up, and you get stuck with references to the child windows and so they won't get garabage collected even after they're closed. 

I've attached some sample code which demonstrates this problem. Attaching a memory profilier, or looking at DialogManager in the debugger will show that every ChildWindow which has had a DialogWindow opened inside it will still be hanging around even when closed.

So, the question is, how can I close (not just hide) the xamDialogWindow so that it, and it's parent container, can be garbage collected?

Thanks,

Richard