ChoiceChip class Null safety

A material design choice chip.

ChoiceChips represent a single choice from a set. Choice chips contain related descriptive text or categories.

Requires one of its ancestors to be a Material widget. The selected and label arguments must not be null.

class MyThreeOptions extends StatefulWidget {
  const MyThreeOptions({Key? key}) : super(key: key);

  @override
  State<MyThreeOptions> createState() => _MyThreeOptionsState();
}

class _MyThreeOptionsState extends State<MyThreeOptions> {
  int? _value = 1;

  @override
  Widget build(BuildContext context) {
    return Wrap(
      children: List<Widget>.generate(
        3,
        (int index) {
          return ChoiceChip(
            label: Text('Item $index'),
            selected: _value == index,
            onSelected: (bool selected) {
              setState(() {
                _value = selected ? index : null;
              });
            },
          );
        },
      ).toList(),
    );
  }
}

See also:

  • Chip, a chip that displays information and can be deleted.
  • InputChip, a chip that represents a complex piece of information, such as an entity (person, place, or thing) or conversational text, in a compact form.
  • FilterChip, uses tags or descriptive words as a way to filter content.
  • ActionChip, represents an action related to primary content.
  • CircleAvatar, which shows images or initials of people.
  • Wrap, A widget that displays its children in multiple horizontal or vertical runs.
  • material.io/design/components/chips.html
Inheritance
Implemented types

Constructors

ChoiceChip({Key? key, Widget? avatar, required Widget label, TextStyle? labelStyle, EdgeInsetsGeometry? labelPadding, ValueChanged<bool>? onSelected, double? pressElevation, required bool selected, Color? selectedColor, Color? disabledColor, String? tooltip, BorderSide? side, OutlinedBorder? shape, Clip clipBehavior, FocusNode? focusNode, bool autofocus, Color? backgroundColor, EdgeInsetsGeometry? padding, VisualDensity? visualDensity, MaterialTapTargetSize? materialTapTargetSize, double? elevation, Color? shadowColor, Color? selectedShadowColor, ShapeBorder avatarBorder})
Create a chip that acts like a radio button. [...]
const

Properties

autofocus bool
True if this widget will be selected as the initial focus when no other node in its scope is currently focused. [...]
final
avatar Widget?
A widget to display prior to the chip's label. [...]
final
avatarBorder ShapeBorder
The shape of the translucent highlight painted over the avatar when the selected property is true. [...]
final
backgroundColor Color?
Color to be used for the unselected, enabled chip's background. [...]
final
clipBehavior Clip
The content will be clipped (or not) according to this option. [...]
final
disabledColor Color?
Color to be used for the chip's background indicating that it is disabled. [...]
final
elevation double?
Elevation to be applied on the chip relative to its parent. [...]
final
focusNode FocusNode?
An optional focus node to use as the focus node for this widget. [...]
final
hashCode int
The hash code for this object. [...]
@nonVirtual, read-only, inherited
isEnabled bool
Whether or not this chip is enabled for input. [...]
read-only, override
key Key?
Controls how one widget replaces another widget in the tree. [...]
final, inherited
label Widget
The primary content of the chip. [...]
final
labelPadding EdgeInsetsGeometry?
The padding around the label widget. [...]
final
labelStyle TextStyle?
The style to be applied to the chip's label. [...]
final
materialTapTargetSize MaterialTapTargetSize?
Configures the minimum size of the tap target. [...]
final
onSelected ValueChanged<bool>?
Called when the chip should change between selected and de-selected states. [...]
final
padding EdgeInsetsGeometry?
The padding between the contents of the chip and the outside shape. [...]
final
pressElevation double?
Elevation to be applied on the chip relative to its parent during the press motion. [...]
final
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
selected bool
Whether or not this chip is selected. [...]
final
selectedColor Color?
Color to be used for the chip's background, indicating that it is selected. [...]
final
selectedShadowColor Color?
Color of the chip's shadow when the elevation is greater than 0 and the chip is selected. [...]
final
shadowColor Color?
Color of the chip's shadow when the elevation is greater than 0. [...]
final
shape OutlinedBorder?
The OutlinedBorder to draw around the chip. [...]
final
side BorderSide?
The color and weight of the chip's outline. [...]
final
tooltip String?
Tooltip string to be used for the body area (where the label and avatar are) of the chip.
final
visualDensity VisualDensity?
Defines how compact the chip's layout will be. [...]
final

Methods

build(BuildContext context) Widget
Describes the part of the user interface represented by this widget. [...]
override
createElement() StatelessElement
Creates a StatelessElement to manage this widget's location in the tree. [...]
inherited
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