MiuixLayerBackdrop class

通过捕获的图层快照提供背景的 MiuixBackdrop。对应 Kotlin LayerBackdrop。

用 MiuixLayerBackdropCapture 包裹背景容器来录制其渲染输出，再把本对象传给模糊组件。用 rememberMiuixLayerBackdrop 或直接 MiuixLayerBackdrop() 创建，需在 dispose 时释放。

Inheritance

Constructors

globalOffset → Offset?: 快照左上角的全局坐标，读取时才计算。对应 Kotlin LayerBackdrop.layerCoordinates 在消费者绘制时读 positionInWindow()，而不是记录录制那一刻的位置。
no setteroverride
hashCode → int: The hash code for this object.
no setterinherited
hasListeners → bool: Whether any listeners are currently registered.
no setterinherited
isCoordinatesDependent → bool: 是否需要布局坐标来正确定位（图层型 backdrop 为 true）。对应 Kotlin isCoordinatesDependent。
no setteroverride
pixelRatio → double: 快照的设备像素比（快照按此比例录制）。
no setteroverride
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
snapshot → Image?: 当前可用于取样的背景快照；未捕获时为 null。
no setteroverride

addListener(VoidCallback listener) → void: Register a closure to be called when the object changes.
inherited
dispose() → void: Discards any resources used by the object.
override
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
notifyListeners() → void: Call all the registered listeners.
inherited
registerCapture(RenderBox capture) → void: 由 MiuixLayerBackdropCapture 的渲染对象在 attach 时登记自身，供 globalOffset 实时取坐标。
removeListener(VoidCallback listener) → void: Remove a previously registered closure from the list of closures that are notified when the object changes.
inherited
toString() → String: A string representation of this object.
inherited
unregisterCapture(RenderBox capture) → void: 由 MiuixLayerBackdropCapture 的渲染对象在 detach / 换 backdrop 时注销。
updateSnapshot(Image image, Offset globalOffset, double pixelRatio) → void: 由 MiuixLayerBackdropCapture 在每帧录制后调用，更新快照与坐标。