private void StartButton_OnClick(object sender, RoutedEventArgs e)
 {
     int n;
     if (int.TryParse(SessionNumber.Text, out n) && Student1ComboBox.SelectedItem != null &&
         Student2ComboBox.SelectedItem != null)
     {
         var learner1Info = ((LearnerInfo)Student1ComboBox.SelectedItem);
         var learner2Info = ((LearnerInfo)Student2ComboBox.SelectedItem);
         if (learner1Info != null && learner2Info != null)
         {
             if (Client != null)
             {
                 var startInfo = new StartMessageInfo()
                 {
                     Students = new List<LearnerInfo>() {learner1Info, learner2Info},
                     SessionId = int.Parse(SessionNumber.Text), /// NOT SAFE AT ALL!!!
                     ScenarioXmlName = "",
                     Language = ScenarioLanguages.English,
                     IsEmpathic = (bool) IsEmpathicCheckBox.IsChecked
                 };
                 Client.LDBPublisher.Start(startInfo.SerializeToJson());
             }
             Started = true;
             CountDownUserControl.Start();
         }
         else
         {
             MessageBox.Show("Select both students", "Warning", MessageBoxButton.OK, MessageBoxImage.Warning);
         }
     }
     else
     {
         MessageBox.Show("Check your input");
     }
 }
 private void StartButton_OnClick(object sender, RoutedEventArgs e)
 {
     
     if (Student1ComboBox.SelectedItem != null)
     {
         var learner1Info = ((LearnerInfo)Student1ComboBox.SelectedItem);
         var learner2Info = ((LearnerInfo)Student2ComboBox.SelectedItem);
         int SessID = Convert.ToInt32(SessionNumberComboBox.SelectedValue);
     
         if (learner1Info != null)
         {
             if (Client != null)
             {
                 var startInfo = new StartMessageInfo()
                 {
                     Students = new List<LearnerInfo>() { learner1Info, learner2Info },
                     SessionId = SessID,//int.Parse(SessionNumberTextBox.Text), /// NOT SAFE AT ALL!!!
                     ScenarioXmlName = (string) ScenarioComboBox.SelectedItem,
                     Language = (ScenarioLanguages)LanguageComboBox.SelectedItem,
                     IsEmpathic = Convert.ToBoolean(IsEmpathicCheckBox.IsChecked),
                 };
                 Client.LDBPublisher.Start(startInfo.SerializeToJson());
             }
             Started = true;
             CountDownUserControl.Start();
             ButtonStop.IsEnabled = true;
             ButtonStart.IsEnabled = false;
         }
         else
         {
             MessageBox.Show("Select the student", "Warning", MessageBoxButton.OK, MessageBoxImage.Warning);
         }
     }
     else
     {
         MessageBox.Show("Check your input");
     }
 }