WP7 - Bind a Listbox to a filtered ObservableCollection

I have an ObservableCollection, and this is MyObject definition:

public class MyObject : INotifyPropertyChanged  
{
    private bool favourite; 
    public event PropertyChangedEventHandler PropertyChanged;   

    public b开发者_运维百科ool Favourite
    {
        get
        {
            return favourite; 
        }
        set
        {
            favourite = value;

            var eh = PropertyChanged;
            if (eh != null)
            {
                eh(this, new PropertyChangedEventArgs("Favourite"));
            }
        }
    }

    public bool Name { get; set; }
}

I want to bind this collection to a WP7 listbox, but only the elements that have the property Favourite = true. How should I bind the listbox to the collection? have in consideration that ObservableCollection, that is a global variable, receives changes (Favourite value) from other parts of the application.

I tried this without success (when the favourite property of one element changes, the listbox is not refreshed):

ObservableCollection<Channel> myChannels = 
    (((App)Application.Current).FavouriteChannels
                               .Where(f=>f.Favorito == true)
                               .OrderBy(o => o.SortIndex)
                               .ToList()).ToObservableCollection<Channel>();

this.listFavoritos.ItemsSource = myChannels;

Any ideas?

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In the last line you should be setting the ItemSource of ListBox to myChannels.

this.listFavoritos.ItemSource = myChannels;

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The simplest solution is to create a seaparate collection which just contains the items you want.

Alternatively, you could use a CollectionViewSource.