WPF的IsKeyboardFocusWithin属性的UWP替代

Question

WPF的IsKeyboardFocusWithin属性是否有UWP替代品？如果没有，您将如何获取焦点是否在其内部。

我宁愿不要手动沿着可视树手动检查每个元素是否集中……

Answer 1

FocusManager.GetFocusedElement将标识焦点元素。然后，您可以使用VisualTreeHelper.GetParent在可视树上行走，以查看它是否是您感兴趣的控件的子级。与逐个节点逐节点检查整个树相比，行走的重量要轻得多。

类似的东西：

    bool IsKeyboardFocusWithin(UIElement element)
    {
        UIElement focused = FocusManager.GetFocusedElement() as UIElement;

        while (focused != null)
        {
            if (focused == element)
            {
                return true;
            }
            focused = VisualTreeHelper.GetParent(focused) as UIElement;
        }
        return false;
    }