AnimatedAlign class Null safety

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.

link
The following code implements the AnimatedAlign widget, using a curve of Curves.fastOutSlowIn.
To create a local project with this code sample, run:
flutter create --sample=widgets.AnimatedAlign.1 mysample

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

Constructors

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

Properties

alignment → AlignmentGeometry
How to align the child.
final
child → Widget?
The widget below this widget in the tree.
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.
nonVirtual">@nonVirtualread-onlyinherited
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
onEnd → VoidCallback?
Called every time an animation completes.
finalinherited
runtimeType → Type
A representation of the runtime type of the object.
read-onlyinherited
widthFactor → double?
If non-null, sets its width to the child's width multiplied by this factor.
final

Methods

createElement() → StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → AnimatedWidgetBaseState<AnimatedAlign>
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">@protectedinherited
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">@nonVirtualinherited