As the title states, I need to return multiple observables or maybe results. The goal is basically to load let's say a library list and then load books based on that library IDs. I don't want to call a service in components, instead I want all the data to be loaded before the page load.
import { Injectable } from '@angular/core';
import { Resolve, ActivatedRouteSnapshot } from '@angular/router';
import { UserService } from './../_services/index';
@Injectable()
export class LibraryResolver implements Resolve<any> {
constructor(private _userService: UserService) {}
resolve(route: ActivatedRouteSnapshot) {
return this._userService.getLibraryList();
}
}
How can I load library list first and then load book info for each library and return to my component?
PS: My service got this method to load by Id
this.userService.getLibraryBooks(this.library["id"]).subscribe((response) => {
// response processing
})
I found a solution for this issue, maybe will help somebody, so basically I've used forkJoin
to combine multiple Observables and resolve all of them.
resolve(route: ActivatedRouteSnapshot): Observable<any> {
return forkJoin([
this._elementsService.getElementTypes(),
this._elementsService.getDepartments()
.catch(error => {
/* if(error.status === 404) {
this.router.navigate(['subscription-create']);
} */
return Observable.throw(error);
})
]).map(result => {
return {
types: result[0],
departments: result[1]
};
});
};
Now it works correctly, as intended.