为什么TreeViewItem中的项目继承父级的事件处理程序？ [英] Why do items in TreeViewItem inherit the event handlers of parent?

问题描述

所以，我创建一个TreeViewItem（parentNode），并将TreeViewItem添加到parentNode TreeViewItem中。然后我将一个MouseButtonEventHandler添加到parentNode，现在parentNode中的所有TreeViewItem都有MouseButtonEventHandler。我已经运行调试器来查看我是否有意外写入添加MouseButtonHandler的代码，但是没有...

So, I create a TreeViewItem (parentNode), and I add TreeViewItems into the parentNode TreeViewItem. I then add a MouseButtonEventHandler to the parentNode, and now all the TreeViewItems inside parentNode have the MouseButtonEventHandler. I've run the debugger to see if I have code that was accidentally written to add the MouseButtonHandler, but there isn't...

编辑：我做了其他测试，甚至下降两个级别。有没有办法将事件处理程序隔离到特定节点而不是其子节点和/或父节点？

I did additional tests, and it even goes two levels down. Is there a way to isolate eventhandlers to only the specific node and not its children and/or parents?

public newClass() {
    TreeViewItem parent = new TreeViewItem();

    TreeViewItem childOne = new TreeviewItem();
    addExpandClickListener(childOne);

    TreeViewItem childTwo = new TreeviewItem();
    TreeViewItem childThree = new TreeViewItem();


    childTwo.Items.Add(childThree);
    childOne.Items.Add(childTwo);
    parent.Items.Add(childOne);
    TreeViewObject.Items.Add(parent);
}

private void addExpandClickListener(TreeViewItem item) { item.MouseLeftButtonUp += new MouseButtonEventHandler(item_MouseClick); }


private void item_MouseClick(object sender, MouseButtonEventArgs e) {
    // Define click event as handled
    e.Handled = true;
    if(sender != e.Source) return;
    // Handle click event
    TreeViewItem root = (TreeViewItem)sender;
    if(root.IsExpanded == true) CollapseRecursive(root);
    else root.IsExpanded = true;
    //else root.ExpandSubtree();
    ViewTree.Items.Refresh();
}

推荐答案

parentNode的区域包括儿童的地区。想想重叠的矩形。如果您只想点击工作的文本部分，您将需要提供自己的DataTemplate或使用可视化树来查找标题并应用点击。

The area of the parentNode includes the areas of the children. Think of overlapping rectangles. If you only want to have a click to work for the text part, you'll either have to supply your own DataTemplate or use the visual tree to find the header and apply the click to that.

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