Radio<T> class

An interactive radio button widget to select a single value from a group.

Interfaces

• Keyboard: When focused is true, pressing Space (' '), Enter ('\n'), or Carriage Return ('\r') selects value and triggers onChanged.
• Mouse: Left-clicking inside bounds selects value and triggers onChanged.

Example Usage

Radio<ThemeMode>(
  value: ThemeMode.dark,
  groupValue: activeTheme,
  label: 'Dark Mode',
  onChanged: (ThemeMode val) {
    setState(() => activeTheme = val);
  },
);

Properties and Styling

Property	Type	Description
value	T	The specific value represented by this radio button.
groupValue	T	The currently selected value of the radio group.
label	String	Descriptive label text next to the radio circle.
onChanged	Function(T)	Callback triggered when this option is selected.
focused	bool	Whether the widget has keyboard focus.
style	Style	Normal rendering style.
focusedStyle	Style	Style applied when focused is true.

Inheritance

• Object
• Widget
• Radio

Implemented types

• Focusable
• KeyEventHandler

Constructors

Radio({required T value, required T groupValue, required String label, required void onChanged(T newValue), bool focused = false, Style style = Style.empty, Style focusedStyle = const Style(modifiers: Modifier.reverse)})

Creates a new Radio.

const

Properties

focused → bool

Whether the widget has keyboard focus.

final

focusedStyle → Style

The rendering style applied when the radio button is focused.

final

groupValue → T

The currently selected value of the radio group.

final

hashCode → int

The hash code for this object.

no setter, inherited

isSelected → bool

Whether this radio button is currently selected.

no setter

key → Key?

The optional key for this widget.

final, inherited

label → String

The descriptive label text next to the radio circle.

final

onChanged → void Function(T newValue)

The callback triggered when this option is selected.

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

style → Style

The normal rendering style.

final

value → T

The specific value represented by this radio button.

final

Methods

createElement() → Element

Creates an Element to manage this widget's location in the tree.

inherited

getIntrinsicHeight(int width) → int

Computes the intrinsic height of this widget under the given width constraint.

inherited

handleKeyEvent(KeyEvent event) → bool

Handles key activations (Space or Enter).

override

handleMouseEvent(MouseEvent event, int localX, int localY) → void

Handles mouse clicks.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

render(Buffer buffer, Rect area) → void

Renders the widget onto the provided buffer within the specified area.

override

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited