ObservableCollection 与 UI 线程

PagedCollectionView taskListView = new PagedCollectionView(cache.Collection4UI);public class TaskCache : SyncCache<Task>{protected override void DoUpdateCache(ObservableCollection<Task> collection){Random random = new Random(102200);int toremove = random.Next(collection.Count);if (toremove > 0){collection.RemoveAt(toremove);}for (int i = 1; i <= 5; i++){collection.Add(new Task(){Area = i / 3D,ProjectName = "公司 " + ((i % 5) + 1).ToString(),TaskName = "Task " + i.ToString(),//Project = list1[i % list1.Count],DueDate = DateTime.Now.AddDays(i),Complete = (i % 2 == 0),Notes = "Task " + i.ToString() + " is due on " + DateTime.Now.AddDays(i) + ". Lorum ipsum..."});}}}public abstract class SyncCache<T>where T : new(){private ObservableCollection<T> _Collection;private ObservableCollection4UI<T> _Collection4UI;private Timer _Timer;public SyncCache(){_Collection = new ObservableCollection<T>();_Collection4UI = new ObservableCollection4UI<T>(_Collection, Deployment.Current.Dispatcher);_Timer = new Timer(CacheUpdateTimerCall);}public ObservableCollection4UI<T> Collection4UI{get { return _Collection4UI; }}public void StartTimer(){_Timer.Change(1000, 1000);}public void StopTimer(){_Timer.Change(-1, -1);}protected abstract void DoUpdateCache(ObservableCollection<T> collection);private void CacheUpdateTimerCall(object state){_Timer.Change(-1, -1);try{this.DoUpdateCache(_Collection);}finally{_Timer.Change(1000, 1000);}}}public class ObservableCollection4UI<T> : ICollection<T>, INotifyCollectionChanged{public ObservableCollection4UI(ObservableCollection<T> collection, Dispatcher dispatcher){this._Source = collection;this._Source.CollectionChanged += new NotifyCollectionChangedEventHandler(Source_CollectionChanged);this._Dispatcher = dispatcher;}void Source_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e){this.OnCollectionChanged(e);}private ObservableCollection<T> _Source;private Dispatcher _Dispatcher;protected void OnCollectionChanged(NotifyCollectionChangedEventArgs e){this._Dispatcher.BeginInvoke(() =>{if (CollectionChanged != null){this.CollectionChanged(this, e);}});}public bool Contains(T item){return _Source.Contains(item);}public void CopyTo(T[] array, int arrayIndex){_Source.CopyTo(array, arrayIndex);}public int Count{get { return _Source.Count; }}public bool IsReadOnly{get { return true; }}#region ICollection<T> 成员void ICollection<T>.Add(T item){throw new NotImplementedException();}void ICollection<T>.Clear(){throw new NotImplementedException();}bool ICollection<T>.Remove(T item){throw new NotImplementedException();}#endregion#region IEnumerable<T> 成员IEnumerator<T> IEnumerable<T>.GetEnumerator(){return _Source.GetEnumerator();}#endregion#region IEnumerable 成员IEnumerator IEnumerable.GetEnumerator(){return _Source.GetEnumerator();}#endregion#region INotifyCollectionChanged 成员public event NotifyCollectionChangedEventHandler CollectionChanged;#endregion}