Checkbox class Null safety

A Material Design checkbox.

The checkbox itself does not maintain any state. Instead, when the state of the checkbox changes, the widget calls the onChanged callback. Most widgets that use a checkbox will listen for the onChanged callback and rebuild the checkbox with a new value to update the visual appearance of the checkbox.

The checkbox can optionally display three values - true, false, and null - if tristate is true. When value is null a dash is displayed. By default tristate is false and the checkbox's value must be true or false.

Requires one of its ancestors to be a Material widget.

This example shows how you can override the default theme of of a Checkbox with a MaterialStateProperty. In this example, the checkbox's color will be Colors.blue when the Checkbox is being pressed, hovered, or focused. Otherwise, the checkbox's color will be Colors.red.

To create a local project with this code sample, run:
flutter create --sample=material.Checkbox.1 mysample

Constructors

Checkbox({Key? key, required bool? value, bool tristate = false, required ValueChanged<bool?>? onChanged, MouseCursor? mouseCursor, Color? activeColor, MaterialStateProperty<Color?>? fillColor, Color? checkColor, Color? focusColor, Color? hoverColor, MaterialStateProperty<Color?>? overlayColor, double? splashRadius, MaterialTapTargetSize? materialTapTargetSize, VisualDensity? visualDensity, FocusNode? focusNode, bool autofocus = false, OutlinedBorder? shape, BorderSide? side}): Creates a Material Design checkbox.
const

Properties

activeColor → Color?: The color to use when this checkbox is checked.
final
autofocus → bool: True if this widget will be selected as the initial focus when no other node in its scope is currently focused.
final
checkColor → Color?: The color to use for the check icon when this checkbox is checked.
final
fillColor → MaterialStateProperty<Color?>?: The color that fills the checkbox, in all MaterialStates.
final
focusColor → Color?: The color for the checkbox's Material when it has the input focus.
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">@nonVirtualread-onlyinherited
hoverColor → Color?: The color for the checkbox's Material when a pointer is hovering over it.
final
key → Key?: Controls how one widget replaces another widget in the tree.
finalinherited
materialTapTargetSize → MaterialTapTargetSize?: Configures the minimum size of the tap target.
final
mouseCursor → MouseCursor?: The cursor for a mouse pointer when it enters or is hovering over the widget.
final
onChanged → ValueChanged<bool?>?: Called when the value of the checkbox should change.
final
overlayColor → MaterialStateProperty<Color?>?: The color for the checkbox's Material.
final
runtimeType → Type: A representation of the runtime type of the object.
read-onlyinherited
shape → OutlinedBorder?: The shape of the checkbox's Material.
final
side → BorderSide?: The color and width of the checkbox's border.
final
splashRadius → double?: The splash radius of the circular Material ink response.
final
tristate → bool: If true the checkbox's value can be true, false, or null.
final
value → bool?: Whether this checkbox is checked.
final
visualDensity → VisualDensity?: Defines how compact the checkbox's layout will be.
final

Methods

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

Constants

width → const double: The width of a checkbox widget.
18.0

Flutter
material
Checkbox class