Display a message for 3 seconds and then continue

Question

I have a very short method that deletes a record from a database, and if successful, then displays a message to the user to confirm that the record has been deleted...

    private void BtnConfirmDelete_Click(object sender, RoutedEventArgs e)
    {
        // Hide "Record deleted" message
        lblDeleteSuccessful.Visibility = Visibility.Hidden;

        // Call interface method to delete record
        Record recInstance = new Record();
        recInstance.DeleteItemFromDatabase<Record>(recordNum);

        // Display "Record deleted" message
        lblDeleteSuccessful.Visibility = Visibility.Visible;
    }

I have tried...

    private void Delay()
    {
        // Will delay for 3 seconds
        DateTime timeNow = DateTime.Now;
        DateTime afterDelay = timeNow.AddSeconds(3);

        do
        {
            // Nothing !!!
        } while (timeNow != afterDelay);
    }

... and...

    private void Delay()
    {
        int delay = 3000; // Three seconds
        Thread.Sleep(delay);
    }

... but neither of these work.

Is there a way to do this??

Answer 1

It looks like you are using something like WPF.

If you are using Thread.Sleep, the whole thread will stop. So if you call the Delay method in the UI-Thread, it will freeze and you will not see any change in the UI.

Instead you can run the code in a different thread, so that the UI thread will be able to change the UI in the meantime.

Here is one way how to implement this using an asynchronous method:

private async Task ToggleVisibilityForThreeSeconds()
{
    lblDeleteSuccessful.Visibility = Visibility.Visible;
    await Task.Delay(3000);
    lblDeleteSuccessful.Visibility = Visibility.Hidden;
}