WPF-如何获取触发TreeViewItem.Loaded事件的TreeViewItem？

Question

I am trying to attach some handlers to each TreeViewItem as they are loaded and then remove the handlers as they are unloaded.

Here is the Code that I have in my custom control which inherits from TreeView :

public ModdedTreeView()
    {
        this.AddHandler(TreeViewItem.LoadedEvent, new RoutedEventHandler(ItemLoaded));            

        this.AddHandler(TreeViewItem.UnloadedEvent, new RoutedEventHandler(ItemUnloaded));
    }

    protected void ItemLoaded(object sender, RoutedEventArgs e)
    {
        TreeViewItem item = e.OriginalSource as TreeViewItem;

        if (item == null)
            return;

        item.AddHandler(TreeViewItem.CollapsedEvent, new RoutedEventHandler(ItemCollapsed));

        item.AddHandler(TreeViewItem.ExpandedEvent, new RoutedEventHandler(ItemExpanded));

        item.AddHandler(TreeViewItem.SelectedEvent, new RoutedEventHandler(ItemSelected));
    }


    protected void ItemUnloaded(object sender, RoutedEventArgs e)
    {
        TreeViewItem item = e.OriginalSource as TreeViewItem;

        if (item == null)
            return;

        item.RemoveHandler(TreeViewItem.CollapsedEvent, new RoutedEventHandler(ItemCollapsed));

        item.RemoveHandler(TreeViewItem.ExpandedEvent, new RoutedEventHandler(ItemExpanded));

        item.RemoveHandler(TreeViewItem.SelectedEvent, new RoutedEventHandler(ItemSelected));
    }

Edit:

I still can not figure out what is going on. It just seems to be picking up the TreeView loaded event instead of the TreeViewItem loaded event.

Answer 1

加载是一个路由事件，因此您可以在OriginalSource属性中找到其源，该属性应该是触发该事件的treeviewitem。

Answer 2

Apparently the TreeViewItem.Loaded event is a direct event. So there is no way to accomplish what I was trying.