protected override void OnPostExecute(string result)
 {
     base.OnPostExecute(result);
     try
     {
         activity.questionList = JsonConvert.DeserializeObject <List <Question> >(result);
         if (activity.questionList.Count != 0)
         {
             QuestionListAdapter adapter = new QuestionListAdapter(Application.Context, activity.questionList);
             list.Adapter       = adapter;
             pgb.Visibility     = ViewStates.Gone;
             holder.Visibility  = ViewStates.Visible;
             holder2.Visibility = ViewStates.Gone;
         }
         else
         {
             pgb.Visibility     = ViewStates.Gone;
             holder.Visibility  = ViewStates.Gone;
             holder2.Visibility = ViewStates.Visible;
         }
     }
     catch (System.Exception ex)
     {
         //activity.topicacctpull.Visibility = ViewStates.Visible;
     }
 }
        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);
            Xamarin.Essentials.Platform.Init(this, savedInstanceState);
            // Set our view from the "View Question" layout resource
            SetContentView(Resource.Layout.view_question_layout);
            manager      = new DataManager();
            btnBack      = FindViewById <Button>(Resource.Id.btnBack);
            listQuestion = FindViewById <ListView>(Resource.Id.listQuestion);

            btnBack.Click += BtnBack_Click;

            adapter = new QuestionListAdapter(this, manager.GetAllQuestion());
            listQuestion.Adapter = adapter;
        }