A widget that makes its child partially transparent.

This class paints its child into an intermediate buffer and then blends the child back into the scene partially transparent.

For values of opacity other than 0.0 and 1.0, this class is relatively expensive because it requires painting the child into an intermediate buffer. For the value 0.0, the child is simply not painted at all. For the value 1.0, the child is painted immediately without an intermediate buffer.

Inheritance

Constructors

Opacity({Key key, @required double opacity, Widget child })

Creates a widget that makes its child partially transparent.

Properties

opacity double

The fraction to scale the child's alpha value.

read-only
child Widget

The widget below this widget in the tree.

read-only, inherited
hashCode int

Get a hash code for this object.

read-only, inherited
key Key

Controls how one widget replaces another widget in the tree.

read-only, inherited
runtimeType Type

A representation of the runtime type of the object.

read-only, inherited

Operators

operator ==(other) bool

The equality operator.

inherited

Methods

createRenderObject(BuildContext context) RenderOpacity

Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget.

debugFillDescription(List<String> description) → void

Add additional information to the given description for use by toString.

updateRenderObject(BuildContext context, RenderOpacity 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.

createElement() SingleChildRenderObjectElement

RenderObjectWidgets always inflate to a RenderObjectElement subclass.

inherited
didUnmountRenderObject(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.

inherited
noSuchMethod(Invocation invocation) → dynamic

Invoked when a non-existent method or property is accessed.

inherited
toString() String

Returns a string representation of this object.

inherited
toStringShort() String

A short, textual description of this widget.

inherited