父子组件 event_bus

event_bus 使用 事件广播 事件监听

    https://pub.dev/packages/event_bus

 

创建 eventBus.dart

 

  import 'package:event_bus/event_bus.dart';

EventBus eventBus = EventBus();

class LoggedInEvent {
  var user;
  LoggedInEvent(this.user);
}

执行的地方

RaisedButton(
  child: Text('向子组件发送'),
  onPressed: () {
    eventBus.fire(LoggedInEvent('你好啊LoggedInEvent'));
  },
),
ChildPage(),

监听的地方, 子组件里

var cancleLoggedInEvent;
@override
initState() {
  super.initState();
  cancleLoggedInEvent = eventBus.on<LoggedInEvent>().listen((event) {
    // Print the runtime type. Such a set up could be used for logging.
    print(event.user);

    change();

  });
}
dispose(){
  super.dispose();
  cancleLoggedInEvent.cancle(); // 取消监听
}

eventBus.on<LoggedInEvent>().listen((event) {}); // 监听单个;
eventBus.on().listen((event) {}); // 监听全部事件