Angular 没有调用订阅的原因是什么

我try 在创建记录时通知用户操作的成功或失败

为此，我准备了以下内容:

Post.actions.ts

export const PostActions = createActionGroup({
  source: 'Create post component',
  events: {
    'Create post': props<{ payload: CreatePostModel }>(),
    'Successful post creation': emptyProps(),
    'Failed post creation': props<{ payload: any }>(),
  },
});

Post.effects.ts

@Injectable()
export class ContentEffects {
  addContent$ = createEffect(() =>
    this.actions$.pipe(
      ofType(PostActions.createPost),
      exhaustMap((action) =>
        this.postService.save(action.payload).pipe(
          map(
            (payload) => PostActions.successfulPostCreation(),
            catchError((error) =>
              of(PostActions.failedPostCreation({ payload: error }))
            )
          )
        )
      )
    )
  );

  constructor(
    private readonly postService: PostService,
    private readonly actions$: Actions
  ) {}
}

Post.reducer.ts

export interface PostState {
  success: string;
  error: any;
}

export const initialState: PostState = { success: '', error: undefined };

export const postReducer = createReducer(
  initialState,
  on(PostActions.successfulPostCreation, (state) => ({
    ...state,
    success: 'shared.success',
    error: undefined,
  })),
  on(PostActions.failedPostCreation, (state, { payload }) => ({
    ...state,
    success: '',
    error: payload,
  }))
);

Post.selectors.ts

export const selectSuccess = createFeatureSelector<string>('success');
export const selectError = createFeatureSelector<any>('error');

Create-post.component.ts

@Component({
  selector: 'app-post-create',
  templateUrl: './post-create.component.html',
  styleUrls: ['./post-create.component.scss'],
})
export class PostCreateComponent implements OnInit {
  @ViewChild('form', { static: false }) form: NgForm;

  success$: Observable<string>;
  error$: Observable<any>;

  constructor(
    private readonly notificationService: NotificationService,
    private readonly store: Store)
  {
    this.success$ = this.store.select(selectSuccess);
    this.error$ = this.store.select(selectError);
  }

  ngOnInit(): void {
    this.success$.subscribe({
      next: (value) => {
        this.form.resetForm();
        this.formGroup.reset();

        this.notificationService.success(value);
      },
    });
    this.error$.subscribe({
      next: (value) => this.notificationService.error(value),
    });
  }

  submit() {
    const model { ... }

    this.store.dispatch(PostActions.createPost({ payload: model }));
  }
}

流程是否成功，我可以验证记录是否已创建，我还可以确认状态的Success属性是否已创建，但不会显示成功通知消息.调试中，我成功地验证了订阅从未被调用

我希望在成功完成这一进程后调用它.

    this.success$.subscribe({
      next: (value) => {
        this.form.resetForm();
        this.formGroup.reset();

        this.notificationService.success(value);
      },
    });

没有调用订阅的原因是什么？

提前谢谢你