The application is having trouble accessing the property 'isXXXXX' because it is undefined

My attempt to utilize a shared service in one of my components has been successful when used with the app's root component. However, I encountered an error when trying to implement it on another module or dashboard.

https://i.sstatic.net/x3rRv.png

shared/authorize.service.ts

@Injectable()
export class AuthorizationService {
  isDoingSomething() {
    return "Some Boolean value";
  }
}

dashboard/header/header.component.ts

@Component({
  selector: 'app-header',
  templateUrl: './header.component.html',
  styleUrls: ['./header.component.css']
})
export class HeaderComponent {
 constructor(private _auth: AuthorizeService,
          private _router: Router) { }
}

dashboard/header/header.component.html

<mat-toolbar color="primary" role="heading">
  <div fxFlex fxLayout fxLayoutAlign="flex-end">
    <ul fxLayout fxLayoutGap="10px" class="navigation-items">
      <li routerLinkActive="active" [routerLinkActiveOptions]="{exact: true}">
        <a routerLink="/home">Home</a>
      </li>
      <li routerLinkActive="active">
        <a *ngIf="_auth.isDoingSomething()" routerLink="/docall">Rest Call</a>
      </li>
    </ul>
  </div>
</mat-toolbar>
**HeaderComponent.html:6 ERROR TypeError:** Cannot read property 'isDoingSomething' of undefined
     at Object.eval [as updateDirectives] (HeaderComponent.html:6)
      at Object.debugUpdateDirectives [as updateDirectives] (core.js:23911)
      at checkAndUpdateView (core.js:23307)

Answer №1

It appears that lazy-loading is being utilized in your application. If so, it is recommended to create a shared module and include your service in its providers array. Then, you can import this shared module into any module where you wish to access the service.

@NgModule({
  imports: [],
  declarations: [],
  exports:[],
  providers: [
     YourService
  ]
})

 export class SharedModule {
}

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