Question

My app has a UserControl that wraps a ServiceController to expose start/stop/restart win service functionality to the user. My concern at the moment is restarting. It takes a small amount of time and I want to reflect the restarting status inside of the control. This is roughly what I have for the restart button click handler

private void RestartButton_Click(object sender, RoutedEventArgs e)
{
    startStopButton.Visibility = Visibility.Hidden;
    restartButton.Visibility   = Visibility.Hidden;
    statusTextBlock.Text = "Restarting...";

    Controller.Stop();
    Controller.WaitForStatus(ServiceControllerStatus.Stopped);
    Controller.Start();
    Controller.WaitForStatus(ServiceControllerStatus.Running);

    startStopButton.Visibility = Visibility.Visible;
    restartButton.Visibility   = Visibility.Visible;

    statusTextBlock.Text = Controller.Status.ToString();
}

Even when I step through the debugger I don’t see these changes reflected in the application. Must be something that I’m missing. Also, I’ve tried disabling the buttons instead of hiding them and that does not work either.

Answer 1

You’re doing everything on the UI thread, so the UI isn’t updated until this code completes. You should do the heavy lifting on a background thread. The BackgroundWorker component makes this easy:

private void RestartButton_Click(object sender, RoutedEventArgs e)
{
    startStopButton.Visibility = Visibility.Hidden;
    restartButton.Visibility   = Visibility.Hidden;
    statusTextBlock.Text = "Restarting...";

    var backgroundWorker = new BackgroundWorker();

    // this delegate will run on a background thread
    backgroundWorker.DoWork += delegate
    {
        Controller.Stop();
        Controller.WaitForStatus(ServiceControllerStatus.Stopped);
        Controller.Start();
        Controller.WaitForStatus(ServiceControllerStatus.Running);
    };

    // this delegate will run on the UI thread once the work is complete
    backgroundWorker.RunWorkerCompleted += delegate
    {
        startStopButton.Visibility = Visibility.Visible;
        restartButton.Visibility   = Visibility.Visible;

        statusTextBlock.Text = Controller.Status.ToString();
    };

    backgroundWorker.RunWorkerAsync();
}