AnimatedContainer class Null safety

Animated version of Container that gradually changes its values over a period of time.

The AnimatedContainer will automatically animate between the old and new values of properties when they change using the provided curve and duration. Properties that are null are not animated. Its child and descendants are not animated.

This class is useful for generating simple implicit transitions between different parameters to Container with its internal AnimationController. For more complex animations, you'll likely want to use a subclass of AnimatedWidget such as the DecoratedBoxTransition or use your own AnimationController.

The following example (depicted above) transitions an AnimatedContainer between two states. It adjusts the height, width, color, and alignment properties when tapped.
To create a local project with this code sample, run:
flutter create --sample=widgets.AnimatedContainer.1 mysample

See also:

Inheritance

Constructors

AnimatedContainer({Key? key, AlignmentGeometry? alignment, EdgeInsetsGeometry? padding, Color? color, Decoration? decoration, Decoration? foregroundDecoration, double? width, double? height, BoxConstraints? constraints, EdgeInsetsGeometry? margin, Matrix4? transform, AlignmentGeometry? transformAlignment, Widget? child, Clip clipBehavior, Curve curve = Curves.linear, required Duration duration, VoidCallback? onEnd})
Creates a container that animates its parameters implicitly. [...]

Properties

alignment AlignmentGeometry?
Align the child within the container. [...]
final
child Widget?
The child contained by the container. [...]
final
clipBehavior Clip
The clip behavior when AnimatedContainer.decoration is not null. [...]
final
constraints BoxConstraints?
Additional constraints to apply to the child. [...]
final
curve Curve
The curve to apply when animating the parameters of this container.
final, inherited
decoration Decoration?
The decoration to paint behind the child. [...]
final
duration Duration
The duration over which to animate the parameters of this container.
final, inherited
foregroundDecoration Decoration?
The decoration to paint in front of the child.
final
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
margin EdgeInsetsGeometry?
Empty space to surround the decoration and child.
final
onEnd VoidCallback?
Called every time an animation completes. [...]
final, inherited
padding EdgeInsetsGeometry?
Empty space to inscribe inside the decoration. The child, if any, is placed inside this padding.
final
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
transform Matrix4?
The transformation matrix to apply before painting the container.
final
transformAlignment AlignmentGeometry?
The alignment of the origin, relative to the size of the container, if transform is specified. [...]
final

Methods

createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree. [...]
inherited
createState() AnimatedWidgetBaseState<AnimatedContainer>
Creates the mutable state for this widget at a given location in the tree. [...]
override
debugDescribeChildren() List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children. [...]
@protected, inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node. [...]
override
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

Operators

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