MaterialStateMouseCursor class

Defines a MouseCursor whose value depends on a set of MaterialStates which represent the interactive state of a component.

This kind of MouseCursor is useful when the set of interactive actions a widget supports varies with its state. For example, a mouse pointer hovering over a disabled FlatButton should not display SystemMouseCursors.click, since the button is not clickable. To solve this, you can use MaterialStateMouseCursor to assign a different cursor (such as SystemMouseCursors.basic) when the FlatButton is disabled.

To use a MaterialStateMouseCursor, you should create a subclass of MaterialStateMouseCursor and implement the abstract resolve method.

In this next example, we see how you can create a MaterialStateMouseCursor by extending the abstract class and overriding the resolve method.

class ButtonCursor extends MaterialStateMouseCursor {
  const ButtonCursor();

  @override
  MouseCursor resolve(Set<MaterialState> states) {
    if (states.contains(MaterialState.disabled)) {
      return SystemMouseCursors.forbidden;
    }
    return SystemMouseCursors.click;
  }

  @override
  String get debugDescription => 'ButtonCursor()';
}

class MyFlatButton extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return FlatButton(
      child: Text('FlatButton'),
      onPressed: () {},
      mouseCursor: const ButtonCursor(),
    );
  }
}

This should only be used as parameters when they are documented to take MaterialStateMouseCursor, otherwise only the default state will be used.

This class also predefines several kinds of material state mouse cursors.

Constructors

MaterialStateMouseCursor(): Creates a MaterialStateMouseCursor.
const

Properties

debugDescription → String: A very short description of the mouse cursor. [...]
read-only, inherited
hashCode → int: The hash code for this object. [...]
read-only, inherited
runtimeType → Type: A representation of the runtime type of the object.
read-only, inherited

Methods

createSession(int device) → MouseCursorSession: Associate a pointing device to this cursor. [...]
@protected, override
debugFillProperties(DiagnosticPropertiesBuilder properties) → void: Add additional properties associated with the node. [...]
@mustCallSuper, @protected, inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a non-existent method or property is accessed. [...]
inherited
resolve(Set<MaterialState> states) → MouseCursor: Returns a MouseCursor that's to be used when a Material component is in the specified state. [...]
override
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: Returns a string representation of this object.
inherited
toStringShort() → String: A brief description of this object, usually just the runtimeType and the hashCode. [...]
inherited

Operators

operator ==(Object other) → bool: The equality operator. [...]
inherited

Constants

clickable → const MaterialStateMouseCursor: A mouse cursor for clickable material widgets, which resolves differently when the widget is disabled. [...]
_EnabledAndDisabledMouseCursor(enabledCursor: SystemMouseCursors.click, disabledCursor: SystemMouseCursors.basic, name: 'clickable')
textable → const MaterialStateMouseCursor: A mouse cursor for material widgets related to text, which resolves differently when the widget is disabled. [...]
_EnabledAndDisabledMouseCursor(enabledCursor: SystemMouseCursors.text, disabledCursor: SystemMouseCursors.basic, name: 'textable')