AnimatedAlignModifier class

Animated version of Align which automatically transitions the child's position over a given duration whenever the given alignment changes.

Here's an illustration of what this can look like, using a curve of Curves.fastOutSlowIn.

For the animation, you can choose a curve as well as a duration and the widget will automatically animate to the new target alignment. If you require more control over the animation (e.g. if you want to stop it mid-animation), consider using an AlignTransition instead, which takes a provided Animation as argument. While that allows you to fine-tune the animation, it also requires more development overhead as you have to manually manage the lifecycle of the underlying AnimationController.

{@tool dartpad} The following code implements the AnimatedAlign widget, using a curve of Curves.fastOutSlowIn.

** See code in examples/api/lib/widgets/implicit_animations/animated_align.0.dart ** {@end-tool}

See also:

  • AnimatedContainer, which can transition more values at once.
  • AnimatedPadding, which can animate the padding instead of the alignment.
  • AnimatedSlide, which can animate the translation of child by a given offset relative to its size.
  • AnimatedPositioned, which, as a child of a Stack, automatically transitions its child's position over a given duration whenever the given position changes.
Inheritance
Available extensions

Constructors

AnimatedAlignModifier({Key? key, Key? modifierKey, Curve curve = Curves.linear, Widget? child, required Duration duration, VoidCallback? onEnd, required AlignmentGeometry alignment, double? heightFactor, double? widthFactor})
Creates a widget that positions its child by an alignment that animates implicitly.
const

Properties

alignment AlignmentGeometry
How to align the child.
final
curve Curve
The curve to apply when animating the parameters of this container.
finalinherited
duration Duration
The duration over which to animate the parameters of this container.
finalinherited
hashCode int
The hash code for this object.
no setterinherited
heightFactor double?
If non-null, sets its height to the child's height multiplied by this factor.
final
key Key?
Controls how one widget replaces another widget in the tree.
finalinherited
modifierKey Key?
The actual key of the widget, which Modifier wrapped
finalinherited
onEnd VoidCallback?
Called every time an animation completes.
finalinherited
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
widthFactor double?
If non-null, sets its width to the child's width multiplied by this factor.
final

Methods

build(BuildContext context) Widget
Describes the part of the user interface represented by this widget.
inherited
buildWithChild(BuildContext context, Widget? child) Widget
A build method that receives an extra child parameter.
override
createElement() SingleChildStatelessElement
Create a SingleChildStatelessElement
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
modified() Modifier

Available on Widget, provided by the ModifierTransformer extension

Transform normal widget to Modifier
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, int wrapWidth = 65}) 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