title: Angular2 Routing with parameters fails
body: <p>I am having troubles (all sorts of errors in very unexpected places) and my best guess is that it happens because of the way routing is set up.</p>
  
  <p>This is my <strong>app-routing.module.ts</strong></p>
  
  <pre><code>const appRoutes: Routes = [
    { path: 'calendar', component: CalendarComponent, canActivate: [AuthGuard] },
    { path: 'calendar/:urlString', component: CalendarComponent, canActivate: [AuthGuard] },
    { path: 'myprofile', component: ProfileComponent, canActivate: [AuthGuard] },
    { path: 'profiles', component: ProfileComponent, canActivate: [AuthGuard] },
    { path: 'locations', component: LocationComponent, canActivate: [AuthGuard] },
    { path: 'login', component: AuthComponent },
    { path: '',   redirectTo: '/login', pathMatch: 'full' }
  ];
  
  @NgModule({
    imports: [ RouterModule.forRoot(appRoutes) ],
    exports: [ RouterModule ]
  })
  </code></pre>
  
  <p>Then, in <strong>CalendarComponent.ts</strong> I have this piece of code:</p>
  
  <pre><code> imports (...)
  
   constructor(
     private activatedRoute: ActivatedRoute,
   ){
   }
  
   public ngOnInit(): void {
      this.activatedRoute.params.subscribe((params: Params) =&gt; {
          this.resolveURLParams(params);
      });
    }
  
    public resolveURLParams( params ): void {
  
      // do stuff based on params
  
    }
  </code></pre>
  
  <p>Anyway, just a half year ago (some RC @Angular2) I could start the app by typing any of these directly into the browser </p>
  
  <p><code>localhost:3000</code>, </p>
  
  <p><code>localhost:3000/calendar</code> or </p>
  
  <p><code>localhost:3000/calendar/2017-05-27</code> </p>
  
  <p>and would get expected results. Now I <em>have</em> to start from <code>localhost:3000</code>, so that <em>the app</em> routes me through <code>../login</code> --> <code>../calendar</code> --> <code>../calendar/2017-05-27</code>, otherwise I get all sorts of troubles, like <code>Cannot read property subscribe of null</code> or <code>Cannot activate already activated outlet</code>.</p>
  
  <p>I guess, the routing has been updated and I am lagging behind. Any help on this, please?</p>