尝试订阅在 Angular 中返回 Observable 的方法

Question

I have a method that returns an Observable:

clockOut(): Observable<boolean> {
    let isClockedOut = new Subject<boolean>();
    isClockedOut.next(false);

    // Some code to clock out and return x

    if (x === true) {
        isClockedOut.next(true);
    }

    return isClockedOut.asObservable();
}

And I'm calling/subscribing to the clockOut() method like so:

ngOnInit() {
    this.clockOut().subscribe((didClockOut: boolean) => {
        if (didClockOut === true) {
            // Do stuff
        }
    });
}

The clockOut() method gets called, and the code inside clockOut() executes properly, but the code block after.subscribe is not being called. Almost like clockOut() isn't returning the Observable?

I'm new to Angular and I've not worked with Observables/Subjects much. Any help is appreciated. Thanks!

Answer 1

The subject does not return old events to new subscriptions, you are triggering, next before returning the observable, so those events are not subscribed yet.

also, you don't have any need for Subject here since everything is synchronous.

if you want last event triggered you can use BehaviorSubject instead of subject