UIElementController

Интерфейс UIElementController представляет собой публичный API контроллера. Контроллер обеспечивает связь между драйвером и отдельным контроллируемым виджетом.

к сведению

Подробнее про роль контроллера можно прочитать в соответствующем разделе

abstract interface class UIElementController {
  /// Typed attributes object (view properties).
  ///
  /// The [attributes] property holds the typed attributes object associated with the controller.
  /// It provides access to the view properties and allows manipulation of their values.
  abstract ViewAttribute attributes;

  /// Id for current controller, same with [ElementTreeEntry] id.
  abstract String id;

  /// Element type.
  ///
  /// The [type] property represents the type of the UI element associated with the controller.
  /// It can be used to identify the type of the element and perform specific operations based on the type.
  abstract String type;

  /// Related action.
  ///
  /// The [action] property represents the related action associated with the controller.
  /// It can be used to perform an action when the UI element is interacted with.
  abstract ServerAction? action;

  /// Reference to the [UIDriver] instance.
  ///
  /// The [driver] property represents a reference to the [UIDriver] instance
  /// that is responsible for driving the UI elements.
  abstract UIDriver driver;

  /// Tag for the controller.
  ///
  /// The [tag] property represents a tag associated with the controller.
  /// It can be used to categorize or identify the controller.
  abstract String? tag;

  /// A stream of remote commands.
  ///
  /// The [commandChannel] property represents a stream of remote commands
  /// that are sent to the controller. The commands are processed by the controller
  /// in order to perform the desired operations (animations, navigation, etc.).
  abstract StreamController<RemoteCommand> commandChannel;

  /// Perform the related action.
  ///
  /// This method is called to perform the related action associated with the controller.
  void performRelatedAction();

  /// Perform the passed action.
  ///
  /// This method is called to perform the passed action.
  void performAction(ServerAction? action);

  /// Perform the related action asynchronously.
  Future<void> performRelatedActionAsync();

  /// Perform the passed action asynchronously.
  Future<void> performActionAsync(ServerAction? action);

  /// Update the state.
  ///
  /// This method is called to update the state of the UI element associated with the controller.
  /// It takes a [newState] parameter of type [ViewAttribute] that represents the new state.
  void updateState(ViewAttribute newState);

  /// Add a listener to [ChangeNotifier].
  ///
  /// This method is called to add a listener to the controller.
  /// It takes a [listener] parameter of type [VoidCallback] that represents the listener function.
  void addListener(VoidCallback listener);

  /// Dispose the controller.
  void dispose();

  /// Detach current controller from the driver.
  ///
  /// The method does not cause ChangeNotifier subscriptions to be destroyed prematurely
  void detach();

  /// RemoveListener the [ChangeNotifier].
  void removeListener(VoidCallback listener);

  /// Listen for remote commands.
  ///
  /// This method allows you to register a callback function that will be
  /// triggered whenever a [RemoteCommand] is received. The callback
  /// function should be a [Future<void> Function(RemoteCommand command)]
  /// and will be executed with the received command as its argument.
  void listenCommand(Future<void> Function(RemoteCommand command) callback);

  /// Emit a remote command.
  ///
  /// This method can be used to emit a remote command to any widgets that
  /// are listening for commands. The command will be sent to all widgets that
  /// are listening.
  ///
  /// The method takes a single parameter of type [RemoteCommand] which is
  /// the command to be emitted.
  FutureOr<void> emitCommand(RemoteCommand command);

  /// Remove the command listener.
  ///
  /// This method is used to remove the listener that was previously registered
  /// with the [listenCommand] method.
  void removeCommandListener();
}

Связанные типы

• RemoteCommand - базовый класс команды
• ViewAttribute - атрибуты элемента
• UIDriver - драйвер UI