app.js

import {Component, View, bootstrap} from 'angular2/angular2';
// import {NewItem} from 'components/new-item';
import {TodoList} from 'components/todo-list';
import {TodoItemsService} from 'services/TodoItemsService';

@Component({
	selector: 'todo-app'
})
@View({
	templateUrl: 'components/app.html',
	directives: [TodoList]
})
export class TodoApp {
	constructor() {
	}
	// other methods
}

bootstrap(TodoApp, [TodoItemsService]);

todo-list.js

import {Component, View, coreDirectives, EventEmitter} from 'angular2/angular2';
import {Inject, bind} from 'angular2/di';
import {TodoItemsService} from 'services/TodoItemsService';

@Component({
	selector: 'todo-list',
})
@View({
	templateUrl: 'components/todo-list.html',
	directives: [coreDirectives]
})
export class TodoList {
  constructor(@Inject('TodoItemsService') todoItems) {
		this.items = todoItems.items;
	}
	
}

TodoItemsService.js

import {Injectable} from 'angular2/angular2';

@Injectable()
export class TodoItemsService {
  items: array = [];
}