customSemanticsActions property

Map<CustomSemanticsAction, VoidCallback> customSemanticsActions

The handlers for each supported CustomSemanticsAction.

Whenever a custom accessibility action is added to a node, the action SemanticAction.customAction is automatically added. A handler is created which uses the passed argument to lookup the custom action handler from this map and invoke it, if present.

Implementation 

Map<CustomSemanticsAction, VoidCallback> get customSemanticsActions => _customSemanticsActions;
void customSemanticsActions= (Map<CustomSemanticsAction, VoidCallback> value)

Implementation 

set customSemanticsActions(Map<CustomSemanticsAction, VoidCallback> value) {
  _hasBeenAnnotated = true;
  _actionsAsBits |= SemanticsAction.customAction.index;
  _customSemanticsActions = value;
  _actions[SemanticsAction.customAction] = _onCustomSemanticsAction;
}