ExpandIcon class Null safety

A widget representing a rotating expand/collapse button. The icon rotates 180 degrees when pressed, then reverts the animation on a second press. The underlying icon is Icons.expand_more.

The expand icon does not include a semantic label for accessibility. In order to be accessible it should be combined with a label using MergeSemantics. This is done automatically by the ExpansionPanel widget.

See IconButton for a more general implementation of a pressable button with an icon.

See also:

Inheritance

Constructors

ExpandIcon({Key? key, bool isExpanded = false, double size = 24.0, required ValueChanged<bool>? onPressed, EdgeInsetsGeometry padding = const EdgeInsets.all(8.0), Color? color, Color? disabledColor, Color? expandedColor})
Creates an ExpandIcon with the given padding, and a callback that is triggered when the icon is pressed.
const

Properties

color Color?
The color of the icon.
final
disabledColor Color?
The color of the icon when it is disabled, i.e. if onPressed is null.
final
expandedColor Color?
The color of the icon when the icon is expanded.
final
hashCode int
The hash code for this object.
@nonVirtual, read-only, inherited
isExpanded bool
Whether the icon is in an expanded state.
final
key Key?
Controls how one widget replaces another widget in the tree.
final, inherited
onPressed ValueChanged<bool>?
The callback triggered when the icon is pressed and the state changes between expanded and collapsed. The value passed to the current state.
final
padding EdgeInsetsGeometry
The padding around the icon. The entire padded icon will react to input gestures.
final
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
size double
The size of the icon.
final

Methods

createElement() StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() State<ExpandIcon>
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.
inherited
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