ngrxstore.service.ts

@Injectable()
export class NgrxStoreService {

	ondestroy$: Observable<void> = new Subject<void>();

	constructor(protected store: Store<State>, protected changeDetector: ChangeDetectorRef) { }

	select<R>(mapFunc: (state: State) => R): Observable<R> {
		return this.store.select(mapFunc).pipe(
			takeUntil(this.ondestroy$),
			tap(() => { this.changeDetector.markForCheck(); })
		);
	}

	set<R>(mapFunc: (state: State) => R, next?: (v: R) => void, error?: (e: any) => void, complete?: () => void) {
		this.select(mapFunc)
			.subscribe(next, error, complete);
	}

	dispatch(action: Action) {
		this.store.dispatch(action);
	}

	ngOnDestroy() {
		(<any>this.ondestroy$).next();
		(<Subject<void>>this.ondestroy$).complete();

	}
}

//usage
@Component({
  // /!\ important part don't forget it (kind of annoying too)
  providers: [NgrxStoreService] 
})
export class Component {
  constructor(private store: NgrxStoreService) {
   store.set( getSelectedItem, item => this.item = item );
   store.select( getSelectedItem ).subscribe(...);
   store.dispatch( SelectAction() );
  }
}