A material design radio button.

Used to select between a number of mutually exclusive values. When one radio button in a group is selected, the other radio buttons in the group cease to be selected. The values are of type T, the type parameter of the Radio class. Enums are commonly used for this purpose.

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

Requires one of its ancestors to be a Material widget.

See also:

Inheritance

Constructors

Radio({Key key, T value, T groupValue, ValueChanged<T> onChanged, Color activeColor })

Creates a material design radio button.

const

Properties

activeColor Color

The color to use when this radio button is selected.

final
groupValue → T

The currently selected value for this group of radio buttons.

final
onChanged ValueChanged<T>

Called when the user selects this radio button.

final
value → T

The value represented by this radio button.

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() → _RadioState<T>

Creates the mutable state for this widget at a given location in the tree.

createElement() StatefulElement

Creates a StatefulElement to manage this widget's location in the tree.

inherited
debugFillDescription(List<String> description) → void

Add additional information to the given description for use by toString.

@mustCallSuper, @protected, inherited
noSuchMethod(Invocation invocation) → dynamic

Invoked when a non-existent method or property is accessed.

inherited
toString() String

Returns a string representation of this object.

inherited
toStringShort() String

A short, textual description of this widget.

inherited

Operators

operator ==(other) bool

The equality operator.

inherited