MVVMCross iOS: Come attivare RowSelected su un TableViewSource personalizzato utilizzando CreateBindingSet?

Question

La mia domanda è per MVVMCross in iOS. Ho un TableView personalizzato e un detailView. Come posso associare il mio "showDetailCommand", quindi quando l'utente fa clic su una delle righe su TableView con trigger RowSelected per passare a detailViewModel?

Qui è la mia struttura di codice:

public class SearchResultsViewModel: MvxViewModel 
{ 
    private MvxCommand _showDetailCommand; 
    public IMvxCommand ShowDetailCommand 
    { 
     get 
     { 
      _showDetailCommand = _showDetailCommand ?? new MvxCommand(ShowDetailCommandHandler); 
      return _showMapCommand; 
     } 
    } 

    private void ShowDetailCommandHandler() 
    { 
     ShowViewModel<ResultDetailViewModel>(new 
      { 
       city = _filter.City, 
       state = _filter.State, 
       interstate = _filter.Interstate, 
       travelPlaza = _filter.SearchTravelPlaza, 
       hasCatScale = _filter.HasCatScale, 
       hasWashoutExpress = _filter.HasWashoutExpress, 
       hasUndercarriage = _filter.HasUndercarriage, 
       nearest = _nearest 
      }); 
    } 
} 

[Register("SearchResults")] 
public class SearchResultsView : MvxTableViewController 
{ 
    public override void ViewDidLoad() 
    { 
       Title = "List"; 
       base.ViewDidLoad(); 
       var source = new TableViewSource(TableView); 

       var bindings = this.CreateBindingSet<SearchResultsView, SearchResultsViewModel>(); 
       bindings.Bind(source).To(vm => vm.Items); 
       bindings.Apply(); 

       TableView.BackgroundColor = UIColor.Clear; 
       TableView.ShowsVerticalScrollIndicator = false; 
       TableView.ScrollEnabled = true; 
       TableView.SeparatorStyle = UITableViewCellSeparatorStyle.None; 
       TableView.Source = source; 

       TableView.ReloadData(); 

    } 

    public class TableViewSource : MvxTableViewSource 
    { 
     public TableViewSource(UITableView tableView) 
      : base(tableView) 
     { 
      tableView.RegisterClassForCellReuse(typeof(TableViewCell), TableViewCell.CellIdentifier); 
     } 

     public override float GetHeightForRow(UITableView tableView, NSIndexPath indexPath) 
     { 
      var item = GetItemAt(indexPath); 
      return TableViewCell.CellHeight(item); 
     } 

     protected override UITableViewCell GetOrCreateCellFor(UITableView tableView, NSIndexPath indexPath, object item) 
     { 
      var cell = tableView.DequeueReusableCell(TableViewCell.CellIdentifier) ?? new TableViewCell(); 
      return cell; 
     } 
    } 

} 

[Register("TableViewCell")] 
public class TableViewCell : MvxTableViewCell 
{ 

    public static readonly NSString CellIdentifier = new NSString("TableViewCell"); 

    public TableViewCell() 
     : base() 
    { 
     Initialise(); 
    } 

    public TableViewCell(IntPtr handle) 
     : base(handle) 
    { 
     Initialise(); 
    } 

    private void Initialise() 
    { 

     var titleLabel = new UILabel(new RectangleF(10, 2, 200, 25)); 
     Add(titleLabel); 

     this.DelayBind(() => 
     { 
      var bindings = this.CreateBindingSet<TableViewCell, SearchResultsItemViewModel>(); 
      bindings.Bind(titleLabel).For(x => x.Text).To(vm => vm.Name); 
      bindings.Bind(??).For(x => x.SelectionChangeCommand).To(vm => vm.showDetailCommand); // what should be in this line ?? 
      bindings.Apply(); 
     }); 

    } 

} 

Answer 1

è possibile associare un comando di visualizzazione modello al SelectionChangedCommand sulla sorgente tavolo.

Questa tecnica è illustrata in diversi campioni - per esempio

• N = 27 http://www.youtube.com/watch?v=h0Eww89c9DM&feature=youtu.be&t=47m30s

• https://github.com/slodge/MvvmCross-Tutorials/tree/master/DailyDilbert

  // command 
  new Cirrious.MvvmCross.ViewModels.MvxCommand<DilbertItem>((dilbertItem) => 
  { 
      // note that we can only pass an id here - do *not* serialiase the whole dilbertItem 
      ShowViewModel<DilbertDetailViewModel>(new { id = dilbertItem.Id }); 
  }); 
  
  // binding 
  set.Bind(source) 
      .For(s => s.SelectionChangedCommand) 
      .To(s => s.ShowDetailCommand); 
  

In alternativa, si può anche mettere i comandi dentro le voci di elenco e può quindi associare all'interno di ogni cella a un SelectedCommand (o qualche altro evento personalizzato all'interno di la tua cella).

Per esempi, consultare alcuni dei campioni con menu - ad es. il campione ValueConversion