文件名：- brief-component.ts我正在调用抽屉服务，如this.assignDrawerService.showDrawer(parameter);
文件名：- drawer-service.ts

private drawerSubject = new BehaviorSubject<boolean>(false);
    public drawer$: Observable<boolean> = this.drawerSubject.asObservable();

 public showDrawer(viewType:any) {
        this.drawerSubject.next(viewType);
        }

文件名：- drawer-component.ts
调试器多次命中

this.assignDrawerService.drawer$.subscribe(viewType => {
      debugger
});

我期待订阅者应该运行一次。我尝试takeUntil，unsuscribe，first