CanActivate不起作用AngularDart 4

自从我从AngularDart的第4版迁移以来,我最近在CanActivate注释方面遇到了一个问题。实际上,CanActivate注释不会运行。

import 'dart:html' as html;

import 'package:angular/angular.dart';
import 'package:angular_router/angular_router.dart';
import 'package:maho_enterprise/app_component.dart';
// Others import

@Component(selector: "view-main"
  ,templateUrl: "main_component.html"
  ,styleUrls: const ["main_component.css"]
  ,directives: const [TopBarComponent,SideBarComponent])
@CanActivate(verifyIfUserIfAuthenticate)
class MainComponent {

}

bool verifyIfUserIfAuthenticate(ComponentInstruction next, ComponentInstruction prev) {
  html.window.console.info("CanActivate works correctly");
  AuthenticationService service = new AuthenticationService.empty();
  bool connected = service.isConnected();
  html.window.console.info("Value connected : "+connected.toString());
  if(!connected) {
    Router router = myInjector.get(Router);
    router.navigateByUrl("/login");
    return false;
  }
  return true;
}

有人在AngularDart的第4版中遇到过这个问题吗? 谢谢你的帮助。