public static async Task AddSampleUserActivity()
        {
            var activityId  = nameof(SchemeActivationSamplePage);
            var displayText = "Sample Activity";
            var description = $"Sample UserActivity added from Application '{Package.Current.DisplayName}' at {DateTime.Now.ToShortTimeString()}";
            var imageUrl    = "http://adaptivecards.io/content/cats/2.png";

            var activityData = new UserActivityData(activityId, CreateActivationDataSample(), displayText, Colors.DarkRed);
            var adaptiveCard = CreateAdaptiveCardSample(displayText, description, imageUrl);

            await UserActivityService.CreateUserActivityAsync(activityData, adaptiveCard);
        }
        private async Task StartupAsync()
        {
            await ThemeSelectorService.SetRequestedThemeAsync();

            // TODO WTS: This is a sample to demonstrate how to add a UserActivity. Please adapt and move this method call to where you consider convenient in your app.
            await UserActivityService.AddSampleUserActivity();

            await FirstRunDisplayService.ShowIfAppropriateAsync();

            Singleton <LiveTileService> .Instance.SampleUpdate();

            await WhatsNewDisplayService.ShowIfAppropriateAsync();

            await Singleton <DevCenterNotificationsService> .Instance.InitializeAsync();

            // TODO WTS: Configure and enable Azure Notification Hub integration.
            //  1. Go to the AzureNotificationsService class, in the InitializeAsync() method, provide the Hub Name and DefaultListenSharedAccessSignature.
            //  2. Uncomment the following line (an exception will be thrown if it is executed and the above information is not provided).
            // await Singleton<AzureNotificationsService>.Instance.InitializeAsync();
        }