Question

I’ve got a standard WPF MainWindow class, and what I’d like is to show a message box using System.Windows.MessageBox, get a response from the user and then run a long running operation (simulated below by a call to Sleep(...)). I’d like to set the cursor to Cursors.Wait before the operation, and back to normal at the end. Here’s what I’ve got:

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    private void ui_button_Click(object sender, RoutedEventArgs e)
    {
        if (MessageBox.Show("Do you want to change the background?", "Change background", MessageBoxButton.YesNo) == MessageBoxResult.No)
        {
            return;
        }

        Cursor = Cursors.Wait;

        Dispatcher.BeginInvoke(DispatcherPriority.Normal, new Action(() =>
            {
                System.Threading.Thread.Sleep(1500);

                if (Background != Brushes.Green)
                {
                    Background = Brushes.Green;
                }
                else
                {
                    Background = Brushes.White;
                }
                Cursor = Cursors.Arrow;
            }));
    }
}

This doesn’t work: the cursor never appears as the wait cursor. However, if I comment out the MessageBox lines, it does work. What’s going on here, and how can I get it to work as intended?

Answer 1

The following code works for me: instead of

Cursor = Cursors.Wait;

try this:

Mouse.OverrideCursor = Cursors.Wait;
Mouse.UpdateCursor();

You turn off the wait cursor the opposite way:

Mouse.OverrideCursor = null;
Mouse.UpdateCursor();