如何異步加載可觀察集合列表？

Question

我正在加載圖片在我的應用程序。它需要一些時間來顯示。

我收集項目作爲可觀察的收集列表，其中圖像存儲在獨立存儲中。

我想異步獲取和顯示圖像？

Answer 1

試一下

public class ObservableCollectionThreadSafe<T> : ObservableCollection<T> 
{ 
    // Override the event so this class can access it 
    public override event NotifyCollectionChangedEventHandler CollectionChanged; 

    public ObservableCollectionThreadSafe() 
    { 
    } 

    public ObservableCollectionThreadSafe(IEnumerable<T> items) 
     : base(items) 
    { 
    } 

    protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e) 
    { 
     // Be nice - use BlockReentrancy like MSDN said 
     using (BlockReentrancy()) 
     { 
      NotifyCollectionChangedEventHandler eventHandler = CollectionChanged; 
      if (eventHandler == null) 
       return; 

      Delegate[] delegates = eventHandler.GetInvocationList(); 

      // Walk thru invocation list 
      foreach (NotifyCollectionChangedEventHandler handler in delegates) 
      { 
       DispatcherObject dispatcherObject = handler.Target as DispatcherObject; 

       // If the subscriber is a DispatcherObject and different thread 
       if (dispatcherObject != null && dispatcherObject.CheckAccess() == false) 
       { 
        // Invoke handler in the target dispatcher's thread 
        dispatcherObject.Dispatcher.Invoke(DispatcherPriority.DataBind, handler, this, e); 
       } 
       else // Execute handler as is 
        handler(this, e); 
      } 
     } 
    } 
} 

編輯：順便說一下，這不是我的代碼，它是在網絡上被人發現......所以「某人」如果你意識到你自己，你應該把它的信用...