MVVMCROSS Binding TimeSyncProblem - ios

Question

I've got a special problem with binding data to an itemsource of an mvxtablieviewsource.
I'm trying to generate a list of favorites, which are generated in the core by clicking on a different tablview.
Normally I get the databinding working like this: (Just basic structure)
controller:
var source = new MySource(TableView);
this.AddBindings(new Dictionary<object, string>
{
{source, "ItemsSource Favs"}
});
Source:
private List<FavModel> _favs;
public override IEnumerable ItemsSource
{
get { return _favs; }
set
{
_favs = (List<FavModel>)value;
ReloadTableData();
}
}
protected override UITableViewCell GetOrCreateCellFor(UITableView tableView, NSIndexPath indexPath, object item)
{
var cell = new AdFavCell();
cell.TextLabel.Text = ((FavModel)item).Display;
return cell;
}
Normally it works really great but no in this case where i generate the data by reacting on users touch, I've got this strange failure;
When I set a breakpoint in the setter of the ItemsSource, and wait for a while then it works correctly.
When I run without a breakpoint the tableview keeps empty.
I also figured out that if I insert a manually pause in the setter then it works too:
Setter with pause:
public override IEnumerable ItemsSource
{
get { return _mydata; }
set
{
_favs = (List<FavModel>)value;
ReloadTableData();
Task.Delay(1000).Wait();
}
}
I also tried to do a delaybinding, but it didn't work.
Have anyone an idea where the problem is?
Edit:
Here some additional Information:
How the Data is generated:
I've got a tableview with content and depending on a longclick on a cell, I create a popumenu where you can add your favorites.
Detecting the longclick:
protected override UITableViewCell GetOrCreateCellFor(UITableView tableView, NSIndexPath indexPath, object item)
{
MvxTableViewCell cell = null;
if (item is SoccerEventListModel)
{
cell = tableView.DequeueReusableCell(this.CellIdentifier) as SoccerEvent;
if (cell == null)
{
cell = new SoccerEvent((SoccerEventListModel)item);
cell.AddGestureRecognizer(new UILongPressGestureRecognizer((e) =>
{
if (e.State == UIGestureRecognizerState.Began)
{
var command = ItemLongClickCommand;
if (command != null)
command.Execute(item);
}
}));
return cell;
}
}
}
Binding the Longclick to the core:
EventListViewModel.EventFavViewCallbackEvent += EventListViewModel_EventFavViewCallbackEvent;
void EventListViewModel_EventFavViewCallbackEvent(EventModel e)
{
var StoreFav = new EventFavoritesView { ViewModel = new EventFavoritesViewModel { ID = e.ID } };
View.Add(StoreFav.View);
}
Depending on the ID of the cell, it creates the list of the favorites by sending a request to our server.
Update:
private long _id;
public long ID
{
get { return _id; }
set { _id = value; RaisePropertyChanged(() => ID); Update(); }
}
When the data is received a RaisePropertyChanged() should make the view to reload its content.
private List<FavModel> _favs;
public List<FavModel> Favs
{
get { return _favs; }
set { _favs = value; RaisePropertyChanged(() => Favs); }
}
ViewModel:
public class EventFavoritesViewModel : MvxViewModel
{
private readonly EventFavoritesService _eventFavoriteService;
private readonly UserFavoritesService _userFavoriteService;
private long _id;
public long ID
{
get { return _id; }
set { _id = value; RaisePropertyChanged(() => ID); Update(); }
}
private string _title;
public string Title
{
get { return _title; }
set { _title = value; RaisePropertyChanged(() => Title); }
}
private List<FavModel> _favs;
public List<FavModel> Favs
{
get { return _favs; }
set { _favs = value; RaisePropertyChanged(() => Favs); }
}
private MvxCommand<FavModel> _itemSelectedCommand;
public System.Windows.Input.ICommand ItemSelectedCommand
{
get
{
_itemSelectedCommand = _itemSelectedCommand ?? new MvxCommand<FavModel>(ToggleFav);
return _itemSelectedCommand;
}
}
public void Init(long eventID)
{
MvxTrace.Trace("We get the details", Logger.Errorlevel.Debug);
ID = eventID;
}
public EventFavoritesViewModel()
{
_eventFavoriteService = new EventFavoritesService(UpdateEventFav);
_userFavoriteService = new UserFavoritesService(UpdateUserFav);
}
private void UpdateUserFav(Fav[] favlist)
{
MvxMessenger.Publish(new UserFavUpdateMessage(this, favlist));
}
private void Update()
{
Favs = _eventFavoriteService.GetFavforEvent(ID).MapToFavs();
}
private void UpdateEventFav(Fav[] favlist)
{
Favs = favlist.MapToFavs();
}
private void ToggleFav(FavModel item)
{
MvxTrace.Trace("Got Item: " + item.Display);
item.NewSubscription = !item.NewSubscription;
}
private IMvxMessenger MvxMessenger
{
get
{
return Mvx.Resolve<IMvxMessenger>();
}
}
public void SaveFavs()
{
foreach (var fav in Favs)
{
if (fav.AlreadySubscribed != fav.NewSubscription)
{
if (fav.NewSubscription)
_userFavoriteService.PutToUserFavorites(fav.MapToFav());
else
_userFavoriteService.DeleteFromUserFavorites(fav.MapToFav());
}
}
}
}
I hope this is enough information, otherwise just tell me.:-)
Thanks for any help.