Struct UndoManager 

pub struct UndoManager { /* private fields */ }

A low-level interface to the system’s undo manager.

To receive events from the system undo manager, create an UndoManagerClient and set it as the client on UndoManager.

The set_undo_state method can be used to update the system’s undo manager using the can_undo and can_redo parameters.

When the system undo or redo button is tapped, the current UndoManagerClient will receive UndoManagerClient::handle_platform_undo with an UndoDirection representing whether the event is “undo” or “redo”.

Currently, only iOS has an UndoManagerPlugin implemented on the engine side. On iOS, this can be used to listen to the keyboard undo/redo buttons and the undo/redo gestures.

See also:

• NSUndoManager

Dart’s UndoManager._instance is instance, the App’s singleton.

Implementations

impl UndoManager

pub fn instance(app: &mut App) -> Handle<UndoManager>

Dart’s UndoManager._instance.

pub fn set_client(app: &mut App, client: Option<AnyUndoManagerClient>)

Receive undo and redo events from the system’s UndoManager.

Setting the client will cause UndoManagerClient::handle_platform_undo to be called when a system undo or redo is triggered, such as by tapping the undo/redo keyboard buttons or using the 3-finger swipe gestures.

pub fn client(app: &mut App) -> Option<AnyUndoManagerClient>

Return the current UndoManagerClient.

pub fn set_undo_state(_app: &mut App, _can_undo: bool, _can_redo: bool)

Set the current state of the system UndoManager. [can_undo] and [can_redo] control the respective “undo” and “redo” buttons of the system UndoManager.

Empty: there is no method channel.

pub fn handle_platform_undo(app: &mut App, direction: UndoDirection)

Flutter UndoManagerClient.handleUndo: the host asked for undo or redo.

Trait Implementations

impl Default for UndoManager

fn default() -> Self

Returns the “default value” for a type.