ArcGISPortalViewer.ViewModel.PortalGroupViewModel.PortalGroupViewModel C# (CSharp) Method

        public PortalGroupViewModel()
        {
            Messenger.Default.Register<ChangeGroupSelectedMessage>(this,
                msg => { PortalGroup = msg.Group; });

            // initialize ListGroupContent RelayCommand
            ListGroupContentCommand = new RelayCommand<ArcGISPortalGroup>(async pg =>
            {
                if (pg == null)
                    return;

                var gsItems = await pg.GetItemsAsync();
                if (gsItems == null || !gsItems.Any())
                    return;

                // filter out any ArcGISPortalItem that is not a WebMap
                var webMapItems = gsItems.Where(item => item.Type == ItemType.WebMap);

                // create an observable collection of the WebMap items
                var groupSharedItems = new ObservableCollection<ArcGISPortalItem>(webMapItems);
                if (!groupSharedItems.Any())
                    return;

                // send ChangePortalItemsCollectionMessage message to other ViewModels who are registered with it.
                Messenger.Default.Send<ChangePortalItemsCollectionMessage>(new ChangePortalItemsCollectionMessage()
                {
                    ItemCollection = groupSharedItems,
                    Title = string.Format("Content of Group: {0}", pg.Title)
                });
                // use the navigation service to navigate to the page showing the specific collection of portal items
                (new NavigationService()).Navigate(App.CollectionPageName);
            });
        }