ObservableCollection不引发CollectionChnaged

Question

我查了几个ObservableCollection的实现，下面是我最后得到的结果。在启动服务时，我得到了添加触发的事件，但是当我调用并更新列表中的对象的属性时，集合根本不通知或触发。

ObservableCollection处理程序

public class iGamingObservableCollection 
{
    ObservableCollection<GameInstance> _contentList;
    public iGamingObservableCollection()
    {
        _contentList = new ObservableCollection<GameInstance>();
        _contentList.CollectionChanged += ContentCollectionChanged;
    }
    public ObservableCollection<GameInstance> ContentList
    {
        get { return _contentList; }
    }

    public void ContentCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
    {
        if (e.Action == NotifyCollectionChangedAction.Remove)
        {
            foreach (GameInstance item in e.OldItems)
            {
                Console.WriteLine("removed: State is now: " + item.InstanceState);
                //Removed items

            }
        }
        else if (e.Action == NotifyCollectionChangedAction.Add)
        {
            foreach (GameInstance item in e.NewItems)
            {
                Console.WriteLine("added: State is now: " + item.InstanceState);
                //Added items
                //item.PropertyChanged += InstancePropertyChange;
            }
        }
        else if (e.Action == NotifyCollectionChangedAction.Replace)
        {
            foreach (GameInstance item in e.NewItems)
            {
                Console.WriteLine("changed: State is now: " + item.InstanceState);
                //Changed items

                //item.PropertyChanged += InstancePropertyChange;

            }
        }
        else if (e.Action == NotifyCollectionChangedAction.Replace)
        {
            foreach (GameInstance item in e.OldItems)
            {
                Console.WriteLine("changed: State is now: " + item.InstanceState);
                //Changed items

                //item.PropertyChanged += InstancePropertyChange;

            }
        }
    }

ObservableCollection控制器

public class InstanceManagerService : IInstanceManager
{
    //TODO: FIX THAT CLASS.. THIS IS INITIAL IMPLEMENTATION!!!
    IGameInstanceRepository instanceRepository;
    iGamingObservableCollection notifyList = new iGamingObservableCollection();
    //private Timer updateNotifierTimer;
    public InstanceManagerService(IGameInstanceRepository instanceRepository)
    {
        this.instanceRepository = instanceRepository;
        populateNotifyList();
        //updateNotifierTimer = new Timer((e) => { populateNotifyList(); }, null, 120 , (int)(TimeSpan.FromMinutes(2).TotalMilliseconds));
    }

    private void populateNotifyList()
    {
        var list = instanceRepository.getInstances();

        foreach (var l in list)
        {
            notifyList.ContentList.Clear();
            notifyList.ContentList.Add(l);
        }
        Console.WriteLine("Notify list content updated.");
    }

public bool releaseInstance(Guid instanceId)
    {
        if (instanceRepository.UpdateGameInstanceToFree(instanceId))
        {
            var notifyTask = notifyList.ContentList.Where(g => g.Id == instanceId).FirstOrDefault();
            notifyTask.InstanceState = InstanceState.Free;

            return true;
        }
        return false;
    }

Answer 1

但是，当我调用和更新列表中的对象的属性时，集合根本不通知或触发。

ObservableCollection不是这样工作的。当在集合中添加/删除对象时，就会触发CollectionChanged。这就是为什么NotifyCollectionChangedAction没有Updated值的原因。要做您想做的事情，在类中实现INotififyPropertyChanged。