private void BtnTerminer_Click(object sender, RoutedEventArgs e) { ac.StopRecord(); Task.Factory.StartNew(() => { //Update Text on the UI thread Application.Current.Dispatcher.BeginInvoke(DispatcherPriority.Input, new Action(() => { var currentActivityIndex = ListActivities.SelectedIndex; var activity = activityListInstance.GetActivity(currentActivityIndex); activityScores[currentActivityIndex] = activity.Courbe_f0_exacteEvaluated ? new Views.CurveResult(activity) : (System.Windows.Controls.UserControl) new Views.FlatResult(activity); this.Results.Content = activityScores[currentActivityIndex]; })); }); BtnDemarrer.IsEnabled = true; BtnLire.IsEnabled = true; BtnTerminer.IsEnabled = false; BtnEcouter.IsEnabled = true; }