Angular 2没有提供程序错误

Question

我正在创建简单的入门应用程序来玩角度2,我正在尝试做一个待办事项服务并将他注入我的组件,我得到这个错误:

没有TodoService的提供商!(TodoList - > TodoService)

TodoService.ts

export class TodoService {
 todos: Array<Object>
 constructor() {
   this.todos = [];
 }
}

app.ts

/// <reference path="typings/angular2/angular2.d.ts" />

import {Component, View, bootstrap, For, If} from 'angular2/angular2';
import {TodoService} from './TodoService'

@Component({
  selector: 'my-app'
})

@View({
  templateUrl: 'app.html',
  directives: [For, If],
  injectables: [TodoService]
})

class TodoList {
 todos: Array<Object>
  constructor(t: TodoService) {
    this.todos = t.todos
  }

  addTodo(todo) {
    this.todos.push({
      done:false,
      todo: todo.value
    });
  }
}

bootstrap(TodoList);

问题是什么？

Answer 1

注射剂是在@Component不在上面指定的@View

你有:

@Component({
  selector: 'my-app'
})

@View({
  templateUrl: 'app.html',
  directives: [For, If],
  injectables: [TodoService]  // moving this line
})

将其更改为:

@Component({
  selector: 'my-app',
  injectables: [TodoService]  // to here
})

@View({
  templateUrl: 'app.html',
  directives: [For, If]
})

这将允许DI将其拾取并将其注入您的组件.