我正在向angulardart移植一个有角度的应用程序,当遇到EventEmitter时,我遇到了一些挑战。
我目前的.ts file
看起来像这样:
import { Component, EventEmitter } from "@angular/core";
@Component({
selector: "app-post-create",
templateUrl: "./post-create.component.html",
styleUrls: ["./post-create.component.css"]
})
export class PostCreateComponent {
enteredTitle = "";
enteredContent = "";
postCreated = new EventEmitter();
onAddPost() {
const post = {
title: this.enteredTitle,
content: this.enteredContent
};
this.postCreated.emit(post);
}
}
根据一篇较老的帖子,EventEmitter is deprecated and shouldn't be used。
我目前的.dart file
看起来像这样:
import 'dart:async';
import 'package:angular/angular.dart';
import 'package:angular_components/angular_components.dart';
import 'package:angular_forms/angular_forms.dart';
@Component(
selector: 'app-post-create',
styleUrls: ['post_create_component.css'],
templateUrl: 'post_create_component.html',
directives: [
MaterialButtonComponent,
materialInputDirectives,
formDirectives
],
providers: [],
)
class PostCreateComponent {
String enteredTitle = '';
String enteredContent = '';
final _postCreatedController = new StreamController<String>();
@Output
Stream<String> get postCreated => _postCreatedController.stream;
onAddPost() {
Map<String, String> post = {
'title': this.enteredContent,
'content': this.enteredContent
};
}
}
我的dart文件需要修复。我没有正确使用Stream。任何帮助表示赞赏。
以下为我工作。您可以使用StreamController.broadcast()。
然后,您可以将对象添加到add()方法。
@Component(
selector: 'new-post',
directives: [coreDirectives,
formDirectives,
FileUploader,
materialInputDirectives,
MaterialButtonComponent],
templateUrl: 'post_new_component.html',
styleUrls: ['post_new_component.css'],
providers: [ClassProvider(PostService)]
)
class PostNewComponent {
final PostService _postService;
final _onDone = new StreamController.broadcast();
String postText;
Post post;
@Input()
Place place;
@Output()
Stream get doneIt => _onDone.stream;
PostNewComponent(this._postService);
Future<void> save() async {
await _postService.create(postText,place.id).then(((_) => _onDone.add(1)));
}
}
在html中,您可以指定“doneIt”事件,该事件触发一个函数。
<new-post (doneIt)="loadPosts()" [place]="place"></new-post>
在父dart组件文件中,您可以添加如下函数:
Future<void> loadPosts() async {
print("broadcast received");
}
我认为你可以使用loadPosts($ event)来传递这个事件,但是你仍然需要自己进行检查。
希望能帮助到你。在这里发布了类似的问题: