ScalableImageWidget class abstract Widget

A widget for displaying a ScalableImage. The image can be automatically scaled by the widget, and fit into the available area with a BoxFit and an Alignment.

Note that rendering a scalable image can be time-consuming if the underlying scene is complex. Notably, GPU performance can be a bottleneck. If animations are played over an unchanging ScalableImage, wrapping the ScalableImageWidget in Flutter's RepaintBoundary might result in significantly better performance.

Inheritance

Constructors

ScalableImageWidget({Key? key, required ScalableImage si, BoxFit fit = BoxFit.contain, Alignment alignment = Alignment.center, bool clip = true, double scale = 1, Color? background, bool isComplex = false, ExportedIDLookup? lookup})
Create a widget to display a pre-loaded ScalableImage. This is the preferred constructor, because the widget can display the SI immediately. It does, however, place responsibility for any asynchronous loading on the caller.
factory
ScalableImageWidget.fromSISource({Key? key, required ScalableImageSource si, BoxFit fit = BoxFit.contain, Alignment alignment = Alignment.center, bool clip = true, double scale = 1, Color? currentColor, Color? background, bool reload = false, bool isComplex = false, ExportedIDLookup? lookup, ScalableImageCache? cache, Widget onLoading(BuildContext)?, Widget onError(BuildContext)?, Widget switcher(BuildContext, Widget child)?})
Create a widget to load and then render a ScalableImage. In a production application, pre-loading the ScalableImage and using the default constructor is usually preferable, because the asynchronous loading that is necessary with an asynchronous source might cause a momentary flash. If the widget is frequently rebuilt, it is generally recommended to provide a cache with an appropriate lifetime and size.
factory

Properties

hashCode → int
The hash code for this object.
no setterinherited
isComplex → bool
Whether the underlying ScalableImage's painting is complex enough to benefit from caching. This is forwarded to CustomPaint -- see CustomPaint.isComplex.
final
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

createElement() → StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → State<StatefulWidget>
Creates the mutable state for this widget at a given location in the tree.
inherited
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent 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

Operators

operator ==(Object other) → bool
The equality operator.
inherited