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如果添加了其他数据流,解析程序将不解析

angular-resolver angular-router angular6 angular

2

Philipp Meissner · 技术社区 · 7 年前

我正试图使用解析器来根据路由持有的给定参数检索数据。

不幸的是,当我添加另一个数据流时,我的数据依赖于解析器,但实际上从未解析。

如果我直接返回一个立即解决的值,一切正常。我调试了情况,看到我收到了所有的部分信息,但最终却没有真正解决。

这是一个快速样品。如果需要更多的代码来理解这个问题,请给我打电话。

我的服务:

export class MyService {
  get(bar) {
    return of(new Foo(bar));
  }
}

secondservice(此服务从后端检索数据):

export class SecondService {
  private readonly _observable: Observable<Bar>;
  constructor() {
    this._observable = merge(
      // Other manipulations
    ).pipe(
      // other manipulations
      shareReplay(1)
    )
  }

  observable(): Observable<Bar> {
    return this._observable;
  }
}

分解器:

export class MyResolver {
  constructor(_secondService: SecondService, _myService: MyService) {}

  resolve(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<Foo> {
    // Does not work - Simply does not resolve
    // return this._secondService
    //   .observable()
    //   .pipe(
    //     switchMap((bar) => this._myService.get(bar)),
    //   );

    // WORKS
    return of(new Foobar('sampleData'));
  }
}

路由器:

const routes: Routes = [
  {
    path: 'someroute',
    component: SomeComponent,
    canActivate: [SomeGuard],
    resolve: {
      myData: MyResolver,
    },
  },
];

组件:

export class SomeComponent implements OnInit {
  constructor(private readonly _route: ActivatedRoute) {}

  ngOnInit() {
    this._route.data
      .subscribe((data) => {
      console.log('received:', data);
      this.myData = data;      
    });
  }
}

somecomponent.html文件

<pre *ngIf="myData">
  Received: {{ myData | json }}
</pre>

2 回复 | 直到 7 年前

1

2

Philipp Meissner 7 年前

take(1) SecondService shareReplay(1)

resolve(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<Foo> {
  return this._secondService
    .observable()
    .pipe(
      take(1),
      switchMap((bar) => this._myService.get(bar)),
  );
}

2

1

eduPeeth 7 年前

Observable.subscribe()

export class MyResolver {
  constructor(_secondService: SecondService, _myService: MyService) {}

  resolve(route: ActivatedRouteSnapshot, state: RouterStateSnapshot): Observable<Foo> {
    // Does not work - Simply does not resolve
     return this._secondService
       .observable()
       .pipe(
         take(1),
         switchMap((bar) => this._myService.get(bar)),
       }     
       );

    // WORKS
    return of(new Foobar('sampleData')).pipe(
         take(1),
         switchMap((bar) => this._myService.get(bar)),          
     });
  }
}