Auto logoff service in wpf application

Question

I'm trying to create a auto logout service in a wpf solution, which is listing to the keyboard and mouse usage. At the moment im using this code( see below ). But it does not take in effect to any windows other than the main. Are there other ways to handle this without being attached to the mainwindow?

 public AutoLogOffService(
            System.Windows.Window applicationWindow,
            IUserProfileManager userProfileManager,
            IDefaultUserDataProvider defaultUserDataProvider,
            IEventAggregator eventAggregator,
            int inactivityInterval)
        {
            _userProfileManager = userProfileManager;
            _defaultUser = defaultUserDataProvider.GetDefaultUser();

            _lastActivity = DateTime.Now;

            var timer = new Timer(1000);
            timer.Elapsed += (sender, args) =>
            {
                //report
                if (DisableAutoLogout)
                {
                    eventAggregator.Publish<ILogOffServiceTimeRemaining>(x =>
                    {
                        x.Percent = 100;
                        x.Seconds = inactivityInterval * 60;
                        x.AutoLogOffDisabled = true;
                    });
                }
                else
                {
                    var remainingSeconds = Convert.ToInt32((_lastActivity.AddMinutes(inactivityInterval) - DateTime.Now).TotalSeconds);
                    remainingSeconds = remainingSeconds < 0 ? 0 : remainingSeconds;
                    var remainingPercent = (int)((double)remainingSeconds / (inactivityInterval * 60) * 100);

                    eventAggregator.Publish<ILogOffServiceTimeRemaining>(x =>
                    {
                        x.Percent = remainingPercent;
                        x.Seconds = remainingSeconds;
                    });
                }

                if (DisableAutoLogout == false && _userProfileManager.CurrentUser != _defaultUser
                    && _lastActivity < DateTime.Now - TimeSpan.FromMinutes(inactivityInterval))
                {
                    DispatcherHelper.SafeInvoke(() => _userProfileManager.CurrentUser = _defaultUser);
                }
            };

            timer.Start();

            var windowSpecificOSMessageListener = HwndSource.FromHwnd(new WindowInteropHelper(applicationWindow).Handle);
            if (windowSpecificOSMessageListener != null)
            {
                windowSpecificOSMessageListener.AddHook((IntPtr hwnd, int msg, IntPtr param, IntPtr lParam, ref bool handled) =>
                {
                    //  Listening OS message to test whether it is a user activity
                    if ((msg >= 0x0200 && msg <= 0x020A) || (msg <= 0x0106 && msg >= 0x00A0) || msg == 0x0021)
                    {
                        //Debug.WriteLine("Message {0:X}", msg);
                        _lastActivity = DateTime.Now;
                    }
                    return IntPtr.Zero;
                });
            }
        }

That's a terrible idea... what would happen if a user had some unsaved work, or changes that they *didn't* want to save, or just left the application at some particular page or position, ready for the next day's work? — Sheridan, May 19 '14 at 14:12
[Related](http://stackoverflow.com/q/5815424/1997232) (hooking keyboard as service). — Sinatr, May 19 '14 at 14:35
@Sheridan . The program is going to be used in a production environment, and the reason for my question is that the program has a lot of popupwindows which is not affected by the this service. — mortenstarck, May 20 '14 at 06:07

score 2 · Accepted Answer · answered May 20 '14 at 08:09

You can access every Window in a WPF Application using the Application.Current.Windows object:

foreach (Window window in Application.Current.Windows)
{
    AutoLogOffService autoLogOffService = new AutoLogOffService(window);
}

You can also just select custom Windows of a particular type

foreach (CustomWindow window in Application.Current.Windows.OfType<CustomWindow>())
{
    AutoLogOffService autoLogOffService = new AutoLogOffService(window);
}

Auto logoff service in wpf application

1 Answers1