How can I complete Observable in RxJS

javascript stream observable rxjs reactivex
ulfryk picture ulfryk · Dec 4, 2015 · Viewed 39.7k times · Source

Let's say we have an Observable:

var observable = Rx.Observable
    .fromEvent(document.getElementById('emitter'), 'click');

How can I make it Complete (what will trigger onComplete event for all subscribed Observers) ?

Answer

user3743222 picture user3743222 · Dec 4, 2015

In this present form, you cannot. Your observable is derived from a source which does not complete so it cannot itself complete. What you can do is extend this source with a completing condition. This would work like :

var end$ = new Rx.Subject();
var observable = Rx.Observable
    .fromEvent(document.getElementById('emitter'), 'click')
    .takeUntil(end$);

When you want to end observable, you do end$.onNext("anything you want here");. That is in the case the ending event is generated by you. If this is another source generating that event (keypress, etc.) then you can directly put an observable derived from that source as an argument of takeUntil.

Documentation:

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