AutomaticNotchShape 继承自： NotchShape

由 ShapeBorder 值创建的凹口形状。

它使用一个形状作为外轮廓，并可选择性地减去第二个形状来形成凹口。这常用于 BottomAppBar 等需要为悬浮操作按钮留出空间的控件。

属性

名称	类型	默认值	说明
host	'ShapeBorder'	required	The shape of the control that uses the notch. This is typically the outer shape of the host control, such as a BottomAppBar. Note: The shape must not depend on text direction.
guest	Optional['ShapeBorder']	None	The shape to subtract from host to create the notch. This is typically the shape of the control the notch should accommodate, such as a FloatingActionButton. If this is None, no notch is cut out even when space for a guest control is available. Note: The shape must not depend on text direction.