ImplicitlyAnimatedWidget class

An abstract class for building widgets that animate changes to their properties.

Widgets of this type will not animate when they are first added to the widget tree. Rather, when they are rebuilt with different values, they will respond to those changes by animating the changes over a specified duration.

Which properties are animated is left up to the subclass. Subclasses' States must extend ImplicitlyAnimatedWidgetState and provide a way to visit the relevant fields to animate.

Relationship to AnimatedWidgets

ImplicitlyAnimatedWidgets (and their subclasses) automatically animate changes in their properties whenever they change. For this, they create and manage their own internal AnimationControllers to power the animation. While these widgets are simple to use and don't require you to manually manage the lifecycle of an AnimationController, they are also somewhat limited: Besides the target value for the animated property, developers can only chose a duration and curve for the animation. If you require more control over the animation (e.g. you want to stop it somewhere in the middle), consider using a AnimatedWidget or one of its subclasses. These widget take an Animation as an argument to power the animation. This gives the developer full control over the animation at the cost of requiring you to manually manage the underlying AnimationController.

Common implicitly animated widgets

A number of implicitly animated widgets ship with the framework. They are usually named AnimatedFoo, where Foo is the name of the non-animated version of that widget. Commonly used implicitly animated widgets include:



ImplicitlyAnimatedWidget({Key key, Curve curve: Curves.linear, @required Duration duration, VoidCallback onEnd})
Initializes fields for subclasses. [...]


curve Curve
The curve to apply when animating the parameters of this container.
duration Duration
The duration over which to animate the parameters of this container.
onEnd VoidCallback
Called every time an animation completes. [...]
hashCode int
The hash code for this object. [...]
@nonVirtual, read-only, inherited
key Key
Controls how one widget replaces another widget in the tree. [...]
final, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited


createState() ImplicitlyAnimatedWidgetState<ImplicitlyAnimatedWidget>
Creates the mutable state for this widget at a given location in the tree. [...]
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node. [...]
createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree. [...]
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
@protected, inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed. [...]
toDiagnosticsNode({String name, DiagnosticsTreeStyle style}) DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
toString({DiagnosticLevel minLevel:}) String
Returns a string representation of this object.
toStringDeep({String prefixLineOne: '', String prefixOtherLines, DiagnosticLevel minLevel: DiagnosticLevel.debug}) String
Returns a string representation of this node and its descendants.
toStringShallow({String joiner: ', ', DiagnosticLevel minLevel: DiagnosticLevel.debug}) String
Returns a one-line detailed description of the object.
toStringShort() String
A short, textual description of this widget.


operator ==(Object other) bool
The equality operator. [...]
@nonVirtual, inherited