RasterWidget class Null safety

A widget that replaces its child with a rasterized version of the child.

By default, the child is drawn as is. The default delegate simply scales down the image by the current device pixel ratio and paints it into the canvas. How this image is drawn can be customized by providing a new subclass of RasterWidgetDelegate to the delegate argument.

Caveats:

The contents of platform views cannot be captured by a raster widget. If a platform view is encountered, then the raster widget will determine how to render its children based on the RasterizeMode. This defaults to RasterizeMode.enabled which will throw an exception if a platform view is encountered.

This widget is not supported on the HTML backend of Flutter for the web.

Inheritance

Constructors

RasterWidget({Key? key, RasterWidgetDelegate delegate = const _RasterDefaultDelegate(), RasterWidgetFallbackDelegate? fallback, RasterizeMode mode = RasterizeMode.enabled, required RasterWidgetController controller, required Widget? child})
Create a new RasterWidget.
const

Properties

child → Widget?
The widget below this widget in the tree.
finalinherited
controller → RasterWidgetController
The controller that determines when to display the children as an image.
final
delegate → RasterWidgetDelegate
A delegate that allows customization of how the image is painted.
final
fallback → RasterWidgetFallbackDelegate?
A fallback delegate which is used if the child layers contains a platform view.
final
hashCode → int
The hash code for this object.
nonVirtual">@nonVirtualread-onlyinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
mode → RasterizeMode
Configuration that controls how the raster widget decides to draw its children.
final
runtimeType → Type
A representation of the runtime type of the object.
read-onlyinherited

Methods

createElement() → SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
createRenderObject(BuildContext context) → RenderObject
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget.
override
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
protected">@protectedinherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
didUnmountRenderObject(covariant RenderObject renderObject) → void
A render object previously associated with this widget has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderObject.
protected">@protectedinherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) → String
A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String
Returns a string representation of this node and its descendants.
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String
Returns a one-line detailed description of the object.
inherited
toStringShort() → String
A short, textual description of this widget.
inherited
updateRenderObject(BuildContext context, covariant RenderRasterWidget renderObject) → void
Copies the configuration described by this RenderObjectWidget to the given RenderObject, which will be of the same type as returned by this object's createRenderObject.
override

Operators

operator ==(Object other) → bool
The equality operator.
nonVirtual">@nonVirtualinherited