//1.定义事件类 class JohwenEvent{ static EventBus eventBus=new EventBus(); } //2.定义事件结构体 class EventData{ var str; EventData(this.str); } void initState() { super.initState(); //3.监听事件 JohwenEvent.eventBus.on<EventData>().listen((event) { setState(() { fuckIndex = event.str; }); }); } //4.触发事件 JohwenEvent.eventBus.fire(new EventData("子类改变了父类文字"));