“Only a single ContentDialog can be open at any time.” error while opening another contentdialog

Question

I am using Windows.UI.Xaml.Controls.ContentDialog to show a confirmation. And based on the response from the first dialog I would (or would not) show another di

Answer 1

I like this answer https://stackoverflow.com/a/47986634/942855, this will allow us ot handle binding all events.

So extended it a little to check the multiple calls to show dialog.

 private int _dialogDisplayCount;
 private async void Logout_OnClick(object sender, RoutedEventArgs e)
        {
            try
            {    
                _dialogDisplayCount++;
                ContentDialog noWifiDialog = new ContentDialog
                {
                    Title = "Logout",
                    Content = "Are you sure, you want to Logout?",
                    PrimaryButtonText = "Yes",
                    CloseButtonText = "No"
                };
                noWifiDialog.PrimaryButtonClick += ContentDialog_PrimaryButtonClick;
                //await noWifiDialog.ShowAsync();
                await noWifiDialog.EnqueueAndShowIfAsync(() => _dialogDisplayCount);
            }
            catch (Exception exception)
            {
                _rootPage.NotifyUser(exception.ToString(), NotifyType.DebugErrorMessage);
            }
            finally
            {
                _dialogDisplayCount = 0;
            }
        }

modified predicate

public class Null { private Null() { } }
    public static class ContentDialogExtensions
    {
        public static async Task EnqueueAndShowIfAsync(this ContentDialog contentDialog, Func predicate = null)
        {
            TaskCompletionSource currentDialogCompletion = new TaskCompletionSource();

            // No locking needed since we are always on the UI thread.
            if (!CoreApplication.MainView.CoreWindow.Dispatcher.HasThreadAccess) { throw new NotSupportedException("Can only show dialog from UI thread."); }
            var previousDialogCompletion = _previousDialogCompletion;
            _previousDialogCompletion = currentDialogCompletion;

            if (previousDialogCompletion != null)
            {
                await previousDialogCompletion.Task;
            }
            var whichButtonWasPressed = ContentDialogResult.None;
            if (predicate == null || predicate() <=1)
            {
                whichButtonWasPressed = await contentDialog.ShowAsync();
            }
            currentDialogCompletion.SetResult(null);
            return whichButtonWasPressed;
        }

        private static TaskCompletionSource _previousDialogCompletion;
    }