Checkbox class

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.

See also:

Inheritance

Constructors

Checkbox({Key key, @required bool value bool tristate: false @required ValueChanged<bool> onChanged, Color activeColor, Color checkColor, Color focusColor, Color hoverColor, MaterialTapTargetSize materialTapTargetSize, FocusNode focusNode, bool autofocus: false })
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
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
hoverColor Color
The color for the checkbox's Material when a pointer is hovering over it.
final
materialTapTargetSize MaterialTapTargetSize
Configures the minimum size of the tap target. [...]
final
onChanged ValueChanged<bool>
Called when the value of the checkbox should change. [...]
final
tristate bool
If true the checkbox's value can be true, false, or null. [...]
final
value bool
Whether this checkbox is checked. [...]
final
hashCode int
The hash code for this object. [...]
read-only, inherited
key Key
Controls how one widget replaces another widget in the tree. [...]
final, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited

Methods

createState() → _CheckboxState
Creates the mutable state for this widget at a given location in the tree. [...]
override
createElement() StatefulElement
Creates a StatefulElement 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.debug }) String
Returns 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 ==(dynamic other) bool
The equality operator. [...]
inherited

Constants

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