WPF full screen on maximize

Question

I basically want to have my WPF window to go in full screen mode, when F11 is pressed or the maximize button in the right top corner of the window is pressed.

While the following works like a charm for pressing F11:

private void Window_KeyDown(object sender, KeyEventArgs e)
{
    if (e.Key == Key.F11)
    {
        WindowStyle = WindowStyle.None;
        WindowState = WindowState.Maximized;
        ResizeMode = ResizeMode.NoResize;
    }
}

This will still displays the Windows taskbar (tested with Windows 7):

protected override void OnStateChanged(EventArgs e)
{
    if (WindowState == WindowState.Maximized)
    {
        WindowStyle = WindowStyle.None;
        WindowState = WindowState.Maximized;
        ResizeMode = ResizeMode.NoResize;
    }
    base.OnStateChanged(e);
}

What am I missing here? Or can I do it even more elegant?

Answer 1

try this

Topmost="True" and WindowState="Maximized"

you can see your window will cover all screen and hide all with windows taskbar

Answer 2

WPF seems to be making the decision about whether to go full-screen or respect the taskbar based on the WindowStyle at the time of maximisation. So a kludgy but effective solution is to switch the window back to non-maximised, set the WindowStyle, and then set the window back to maximised again:

private bool _inStateChange;

protected override void OnStateChanged(EventArgs e)
{
  if (WindowState == WindowState.Maximized && !_inStateChange)
  {
    _inStateChange = true;
    WindowState = WindowState.Normal;
    WindowStyle = WindowStyle.None;
    WindowState = WindowState.Maximized;
    ResizeMode = ResizeMode.NoResize;
    _inStateChange = false;
  }
  base.OnStateChanged(e);
}

Although the code is obviously ugly, the transition to Normal and then back to Maximized doesn't seem to make the user experience any worse. On my display, I noticed flicker with both the F11 code and the kludge maximise, but not noticeably worse on the kludge maximise. But your mileage may vary!

Answer 3

If you happen to be using WindowChrome to create a custom chrome experience, you'll need to set the GlassFrameThickness to something other than 0 (at least that was the last thing I needed to do to get the TaskBar to be hidden behind the window). That is in addition to the steps provided in the accepted answer.

Answer 4

In my case, minimizing and maximizing will make the fullscreen size to be a little bit bigger than the screen, so the alternative I found is to temporarily set the Visibility to Collapsed then back to Visible afterwards to force redraw.

Visibility = Visibility.Collapsed;
WindowStyle = WindowStyle.None;
WindowState = WindowState.Maximized;
ResizeMode = ResizeMode.NoResize;
Visibility = Visibility.Visible;

Answer 5

I have found easy way to achieve fullscreen in WPF:

    private double LastHeight, LastWidth;
    private System.Windows.WindowState LastState;

    private void Window_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.Key == Key.F11)
        {
            if (WindowStyle != WindowStyle.None)
            {
                LastHeight = Height;
                LastWidth = Width;
                LastState = WindowState;

                Topmost = true;
                Width = System.Windows.Forms.Screen.PrimaryScreen.Bounds.Width;
                Height = System.Windows.Forms.Screen.PrimaryScreen.Bounds.Height;
                Top = 0;
                Left = 0;
                WindowState = System.Windows.WindowState.Normal;
                WindowStyle = WindowStyle.None;
                ResizeMode = System.Windows.ResizeMode.NoResize;
            }
            else
            {
                WindowStyle = WindowStyle.SingleBorderWindow;
                WindowState = LastState; ;
                ResizeMode = ResizeMode.CanResizeWithGrip;
                Topmost = false;
                Width = LastWidth;
                Height = LastHeight;
            }
        }
    }

This works good in Windows 7 with fixed Taskbar.

Answer 6

If there is still someone that need a smooth full screen of course tested only on windows 10! In windows 10 minimized do less flickering if you maintain this code order!

    public bool IsFullscreen = false;
    public WindowState lastWindowState;
    private void player_MouseDoubleClick(object sender, MouseButtonEventArgs e)
    {
        if (IsFullscreen)
        {
            this.WindowStyle = WindowStyle.SingleBorderWindow;
            this.WindowState = lastWindowState;
            IsFullscreen = false;

        }
        else
        {
            lastWindowState = this.WindowState;

            this.WindowStyle = WindowStyle.None;
            if (this.WindowState == WindowState.Maximized)
                this.WindowState = WindowState.Minimized;
            this.WindowState = WindowState.Maximized;
            IsFullscreen = true;
        }
    }