将一些事件信息从子组件发送到父组件

Question

我想将 int 值从子组件传递到其父组件。事件本身正确到达，但我在父级的接收方法中添加 Event 参数时失败。

更新：编辑代码以缩小，但完整的示例

---

import 'package:angular2/core.dart';
class MyItem {
  int id = 1;
}

@Component(
    selector: 'my-list',
    directives: const [MyListItem],
    template: '''
<div *ngFor='let myItem of myItems'>
  <my-list-item [myItem]='myItem' (dirtiesParent)='doInit($event)'></my-list-item>
</div>
''')
class MyList {
  @Input()
  List<MyItem> myItems = [ new MyItem() ];
  void doInit() {
    print("got event");
  }
}

@Component(
    selector: 'my-list-item',
    template: '''
<div>id {{myItem.id}}<button (click)='doDelete()'>delete</button></div>
''')
class MyListItem {
  @Input()
  MyItem myItem;
  @Output()
  EventEmitter<int> dirtiesParent = new EventEmitter();
  void doDelete() {
    dirtiesParent.add(myItem.id);
  }
}

Answer 1

我认为你只是不恰当地逃脱了$.试试这个：

class MyItem {
  int id = 1;
}
@Component(
    selector: 'my-list',
    directives: const [MyListItem],
    template: '''
<div *ngFor='let myItem of myItems'>
  <my-list-item [myItem]='myItem' (dirtiesParent)='doInit($event)'></my-list-item>
</div>
''')
class MyList {
  @Input()
  List<MyItem> myItems = [new MyItem()];
  void doInit(int id) {
    print("got event for id $id");
  }
}
@Component(
    selector: 'my-list-item',
    template: '''
<div>id {{myItem.id}}<button (click)='doDelete()'>delete</button></div>
''')
class MyListItem {
  @Input()
  MyItem myItem;
  @Output()
  EventEmitter<int> dirtiesParent = new EventEmitter();
  void doDelete() {
    dirtiesParent.add(myItem.id);
  }
}

这对我有用（它打印"id 1 的获取事件"）。请注意，我还在 doInit() 中添加了预期的参数。