private void OpenGlobalCommandExecute(UserViewModel user)
 {
     NavigationService.Navigate(ViewLocator.SendRequest, user);
 }
 private async Task OpenLocalCommandExecute(UserViewModel user)
 {
     var dialogsManager = ServiceLocator.Locator.Get<IDialogsManager>();
     var userDialog = dialogsManager.Dialogs.FirstOrDefault(d => d.DialogType == DialogType.Private && d.OccupantIds.Contains(user.UserId));
     if (userDialog != null)
     {
         NavigationService.Navigate(ViewLocator.Chat, new ChatNavigationParameter { Dialog = userDialog });
     }
     else
     {
         var response = await QuickbloxClient.ChatClient.CreateDialogAsync(user.FullName, DialogType.Private, user.UserId.ToString());
         if (response.StatusCode == HttpStatusCode.Created)
         {
             var dialogVm = DialogViewModel.FromDialog(response.Result);
             dialogVm.Image = user.Image;
             dialogVm.PrivatePhotoId = user.ImageUploadId;
             dialogVm.Name = user.FullName;
             dialogsManager.Dialogs.Insert(0, dialogVm);
             NavigationService.Navigate(ViewLocator.Chat, new ChatNavigationParameter { Dialog = dialogVm });
         }
     }
 }