Question

我有以下方法（在棱镜的RegionAdapter中）。

protected override void Adapt(IRegion region, DocumentPane regionTarget)
{
    region.Views.CollectionChanged += delegate(object sender, NotifyCollectionChangedEventArgs e)
    {
        OnViewsCollectionChanged(sender, e, region, regionTarget);
    };
}

我的问题是，通过这种方式订阅事件，我有内存泄漏。但是region和regionTarget参数是Adapt的局部变量。

我试着查看是否有人以不同的方式处理该场景，但MSDN和MVP都使用这种漏洞的方法......

我该如何处理它以便以后可以取消订阅该事件？

修改
上面的代码只是一个例子，我认为这清楚地说明了问题泄漏内存的实际代码如下：

private void OnViewsCollectionChanged(object sender, 
    NotifyCollectionChangedEventArgs e, IRegion region, 
    DocumentPane regionTarget)
{
    if (e.Action == NotifyCollectionChangedAction.Add)
    {
        //Add content panes for each associated view.
        foreach (object item in e.NewItems)
        {
            UIElement view = item as UIElement;

            if (view != null)
            {
                DockableContent newContentPane = new DockableContent();
                newContentPane.IsCloseable = true;
                newContentPane.HideOnClose = false;

                ScrollViewer sViewer = new ScrollViewer()
                {
                    Content = item,
                    HorizontalScrollBarVisibility = ScrollBarVisibility.Auto,
                    VerticalScrollBarVisibility = ScrollBarVisibility.Auto
                };
                newContentPane.Content = sViewer;

                //When contentPane is closed remove the associated region
                // (MEMORY LEAK)
                newContentPane.Closed += (contentPaneSender, args) =>
                {
                    DockableContent docker =
                        contentPaneSender as DockableContent;
                    ScrollViewer scroller = docker.Content as ScrollViewer;
                    region.Remove(scroller.Content);
                    IDisposable dispView = scroller.Content as IDisposable;
                    if (dispView != null) dispView.Dispose();
                    scroller.Content = null;
                };
                regionTarget.Items.Add(newContentPane);
                newContentPane.Activate();
            }
        }
    }
}

谢谢，

巴布。

Answer 1

使用具体方法代替匿名。例如：

   private Region _region;
   DocumentPane _regionTarget
   protected override void Adapt(IRegion region, DocumentPane regionTarget)
    {
        _region = region;
        _regionTarget = regionTarget;
        region.Views.CollectionChanged += OnCollectionChanged;
    }

    private void OnCollectionChanged (object sender, NotifyCollectionChangedEventArgs e) 
    {
        OnViewsCollectionChanged(sender, e, _region, _regionTarget);
    }

    ...
    private void Unsubscribe() 
    {
      _region.Views.CollectionChanged -= OnCollectionChanged;
    }

内存泄漏和局部变量

1 个答案: