Question

I am using Window.ShowDialog() to open a modal window in my WPF (MVVM) application, but it lets me navigate to other windows using the Windows taskbar (Windows 7).

Consider this:
I have 3 non-modal windows open in my application. Now One of these opens a modal window using Window.ShowDialog(). I also set Application.MainWindow as the owner of the modal window. This is so because I am using MVVM messaging and the message handler to open a new window is centralized in App.xaml.cs. The window does opens modally – no issues there. However, Windows 7 allows me to swtich to the other application windows from the taskbar. This leads to a situation where the modal window goes behind another window, which I prefer not to have.

I can’t do anything on other windows as long as I have the modal open, but it would be nice if the modal window always remained on top as long as it’s open. Is there a way I can disable taskbar switching when the modal is open? FYI – all open windows launched from the app appear as separate entries on the taskbar.

Thanks in advance!

Answer 1

There isn’t any code to base this off of, but it sounds like you have left off some properties on the Window you’ve created and expected ShowDialog to apply additional “dialog” semantics:

Window window = new Window()
{
    Title = "Modal Dialog",
    ShowInTaskbar = false,               // don't show the dialog on the taskbar
    Topmost = true,                      // ensure we're Always On Top
    ResizeMode = ResizeMode.NoResize,    // remove excess caption bar buttons
    Owner = Application.Current.MainWindow,
};

window.ShowDialog();