protected override void OnSourceInitialized(EventArgs e)
{
if (!(PresentationSource.FromVisual(this) is HwndSource source))
{
throw new InvalidOperationException("Cannot find a valid HwndSource");
}
_keyboardHwndSourceHook = new KeyboardHwndSourceHook(source, true);
_keyboardHwndSourceHook.KeyPressed += OnKeyPressed;
_keyboardHwndSourceHook.InputDeviceChange += OnInputDeviceChange;
_keyboardDevices = RawKeyboardDevice.GetDevices();
DeviceCount = _keyboardDevices.Count;
base.OnSourceInitialized(e);
}
private void OnInputDeviceChange(object sender, EventArgs e)
{
_keyboardDevices = RawKeyboardDevice.GetDevices();
}