WPF in "Kiosk" mode - how to get back application focus when it lost it?

Question

Hello,

We are using WPF aplication in "Kiosk" mode like this:

Window w = new Window();
w.WindowStyle = WindowStyle.None;
w.WindowState = WindowState.Maximized;
w.TopMost = true;
w.ResizeMode=NoResize;
w.Show();

Sometimes taskbar shows (look here for this invalid state ), i.e. when system yellow info balloon shows near the clock - no network connection, system info...etc., and our application lost focus.
How we can get our application focus when it lost it automatically but not to compromise keyboard focus?

we have a barcode scanner so when it scans our application textbox should show the scanned value no matter if application is in focus or not.

Regards
Matjaž

Answer 1

I believe you can call UIElement.Focus() (on any event handler) to set focus on an UIElement (including Window, in your case, perhaps w.Focus()) and it makes the window actived.

---

William

Answer 2

w.Focus() didn't helped us but this helped (using Interop):

//Interop.cs
using System.Runtime.InteropServices;
using System.Windows.Interop;

public class Interop
{
        [DllImport("user32.dll")]
        public static extern bool SetForegroundWindow(IntPtr hWnd);

        [DllImport("user32.dll")]
        public static extern IntPtr GetForegroundWindow();

        public static IntPtr GetWindowHandle(Window window)
        {
            return new WindowInteropHelper(window).Handle;
        }
}

//Somewhere in main window
IntPtr window = Interop.GetWindowHandle(this);
IntPtr focused = Interop.GetForegroundWindow();
if (window != focused)
{
    Interop.SetForegroundWindow(window);
}

So it is solved.

Regards
Matjaž