AngularDart英雄之旅教程抛出错误“英雄”不是函数吗？

Question

error: 'Hero' isn't a function. (invocation_of_non_function at [angular_dart_tour_of_heroes] lib\\app_component.dart:18)

hero.dart

class Hero {
  final int id;
  String name;

  Hero(this.id, this.name);
}

app_component.dart

import 'package:angular/angular.dart';
import 'package:angular_components/angular_components.dart';

import 'hero.dart';

@Component(
  selector: 'my-app',
  styleUrls: const ['app_component.css'],
  templateUrl: 'app_component.html',
  directives: const [materialDirectives,],
  providers: const [materialProviders],
)
class AppComponent {
  final title = 'Tour of Heroes';
  Hero hero = Hero(1, 'Windstorm');

}

app_component.html

<h1>{{title}}</h1>
<h2>{{hero.name}}</h2>
<div><label>id: </label>{{hero.id}}</div>
<div><label>name: </label>{{hero.name}}</div>

Answer 1

听起来您使用的Dart版本太旧，仍然需要new可选版本

Answer 2

It seems like you are using a Angular 5 / Dart 2 version of the tutorial under Dart 1. Which version of the Dart SDK are you using? (Run: dart --version ).

I'd suggest using Angular 2 and Dart 2 .

If you want to use Dart 1.24.3 , then you'll need the Angular 4 version of the tutorial .