UWP 替代 WPF 的 IsKeyboardFocusWithin 属性

Question

WPF IsKeyboardFocusWithin 属性 是否有 UWP 替代品？如果不是，您将如何确定焦点是否在其内部。

我宁愿不手动走下可视化树检查每个元素是否聚焦...

Answer 1

FocusManager.GetFocusedElement will ID the focused element. You can then walk up the Visual Tree with VisualTreeHelper.GetParent 看看它是否是您感兴趣的控件的子控件。向上走比逐个节点检查整个树的重量要轻得多。

类似于：

    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;
    }