Ich möchte eine ObservableCollection nach Typ (Typ AddPoint) in eine Teilmenge filtern und sie ohne Duplikate aufsteigend sortieren. Meine Basisklasse ist ModelBase mit den Unterklassen AddPoint, Time, Repeat usw. Die ObservableCollection MotionSequenceCollection wird mit diesen Typen in beliebiger Reihenfolge gefüllt, und einige werden dupliziert.

Ich habe es mehrere Male versucht und sie unten in der ICollectionView-Eigenschaft gezeigt, von der ich 'gezogen' habe:Teilmenge der Sammlung binden.

BEOBACHTBARE SAMMLUNG

private ObservableCollection<ModelBase> _motionSequenceCollection = 
        new ObservableCollection<ModelBase>();

    public ObservableCollection<ModelBase> MotionSequenceCollection
    {
        get
        {
            return _motionSequenceCollection;
        }

        set
        {
            if (_motionSequenceCollection == value)
            {
                return;
            }

            var oldValue = _motionSequenceCollection;
            _motionSequenceCollection = value;

            // Update bindings, no broadcast
            RaisePropertyChanged();
        }
    }

    public ICollectionView Location
    {
        get
        {
             var location = CollectionViewSource.GetDefaultView(_motionSequenceCollection);

            //DOES NOT WORK.  PROBLEM: GetType() creates type of system.type() and AddPoint, which don't work.  Need a cast, or something??  
            // found at https://stackoverflow.com/questions/9621393/bind-subset-of-collection  The problem is that there is an error:
            //    Cannot apply operator '==' to operands of type 'System.Type' and 'MotionSeq.Model.AddPoint',
            //    candidates are:
            //          bool ==(System.Reflection.MemberInfo, System.Reflection.memberInfo) (in class MemberInfo)
            //          bool ==(System.type, System.Type) (in class Type)
            //location.Filter = p => (p as ModelBase).GetType() == AddPoint;

            //DOES NOT WORK.  PROBLEM: Affects the main collection and won't let TIME type added.
            //location.Filter = o1 => (o1 is AddPoint);

            //DOES NOT WORK.  PROBLEM: Sorts fine, but also sorts MotionSequenceCollection!!  What up w/ that!?  
            //location.SortDescriptions.Add(new SortDescription("AddPointClassName", ListSortDirection.Ascending));

            //DOES NOT WORK.  PROBLEM: MotionSequenceCollection does not update.
            //location.Filter = p => (p as ModelBase) == AddPoint;

            //DOES NOT WORK.  PROBLEM: Source is not instantiated(?) and exmaple from stackoverflow and not sure how that got there in the first place.
            //source.Filter = p => (p as ModelBase).GetType() == "AddPoint";
            //return source;

            return location;
        }
    }