SizeTransitionModifier class

Animates its own size and clips and aligns its child.

SizeTransition acts as a ClipRect that animates either its width or its height, depending upon the value of axis. The alignment of the child along the axis is specified by the axisAlignment.

Like most widgets, SizeTransition will conform to the constraints it is given, so be sure to put it in a context where it can change size. For instance, if you place it into a Container with a fixed size, then the SizeTransition will not be able to change size, and will appear to do nothing.

Here's an illustration of the SizeTransition widget, with it's sizeFactor animated by a CurvedAnimation set to Curves.fastOutSlowIn:

{@tool dartpad} This code defines a widget that uses SizeTransition to change the size of FlutterLogo continually. It is built with a Scaffold where the internal widget has space to change its size.

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

See also:

  • AnimatedCrossFade, for a widget that automatically animates between the sizes of two children, fading between them.
  • ScaleTransition, a widget that scales the size of the child instead of clipping it.
  • PositionedTransition, a widget that animates its child from a start position to an end position over the lifetime of the animation.
  • RelativePositionedTransition, a widget that transitions its child's position based on the value of a rectangle relative to a bounding box.
Inheritance
Available extensions

Constructors

SizeTransitionModifier({Key? key, Widget? child, Key? modifierKey, Axis axis = Axis.vertical, required Animation<double> sizeFactor, double axisAlignment = 0.0})
Creates a size transition.
const

Properties

axis Axis
Axis.horizontal if sizeFactor modifies the width, otherwise Axis.vertical.
final
axisAlignment double
Describes how to align the child along the axis that sizeFactor is modifying.
final
hashCode int
The hash code for this object.
no setterinherited
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
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
sizeFactor Animation<double>
The animation that controls the (clipped) size of the child.
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
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}) 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