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TreeViewItem被选定激发两次
原标题:TreeViewItem isSelected fired twice

我有一个包含各种项目的TreeView。Items被设置为使得IsSelected属性被绑定到我的VM到bool IsSelected。

每当我单击一个树视图项时,这个VM属性就会被调用两次,第一次调用的值为==false,然后调用的值是==true。

我认为这是一种正常的行为,但我不确定为什么,因为我以同样的方式绑定了IsExpended属性,并且只被调用一次。

谢谢

最佳回答

我怀疑原因是当你选择一个项目时,首先取消选择旧项目,然后选择新项目。这导致第一次调用false,第二次调用true。

也许在调试时,检查视图模型上的DisplayName或类似属性,看看每次修改哪些项,看看情况是否确实如此。

同样,当您展开一个节点时,不需要折叠任何其他节点。因此,它只是扩展您尝试扩展的节点(对于IsExpanded为true)。

问题回答

其原因是冒泡事件。

当一个事件被引发时,它将“冒泡”起来,直到它被处理为止。

您可以通过选择第三级项目来验证它。

您只需要设置<code>e.Handled=true</code>;

Ofir公司





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