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- "use strict";
- var __extends = (this && this.__extends) || function (d, b) {
- for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
- function __() { this.constructor = d; }
- d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
- };
- var Subscriber_1 = require('../Subscriber');
- var Notification_1 = require('../Notification');
- /**
- *
- * Re-emits all notifications from source Observable with specified scheduler.
- *
- * <span class="informal">Ensure a specific scheduler is used, from outside of an Observable.</span>
- *
- * `observeOn` is an operator that accepts a scheduler as a first parameter, which will be used to reschedule
- * notifications emitted by the source Observable. It might be useful, if you do not have control over
- * internal scheduler of a given Observable, but want to control when its values are emitted nevertheless.
- *
- * Returned Observable emits the same notifications (nexted values, complete and error events) as the source Observable,
- * but rescheduled with provided scheduler. Note that this doesn't mean that source Observables internal
- * scheduler will be replaced in any way. Original scheduler still will be used, but when the source Observable emits
- * notification, it will be immediately scheduled again - this time with scheduler passed to `observeOn`.
- * An anti-pattern would be calling `observeOn` on Observable that emits lots of values synchronously, to split
- * that emissions into asynchronous chunks. For this to happen, scheduler would have to be passed into the source
- * Observable directly (usually into the operator that creates it). `observeOn` simply delays notifications a
- * little bit more, to ensure that they are emitted at expected moments.
- *
- * As a matter of fact, `observeOn` accepts second parameter, which specifies in milliseconds with what delay notifications
- * will be emitted. The main difference between {@link delay} operator and `observeOn` is that `observeOn`
- * will delay all notifications - including error notifications - while `delay` will pass through error
- * from source Observable immediately when it is emitted. In general it is highly recommended to use `delay` operator
- * for any kind of delaying of values in the stream, while using `observeOn` to specify which scheduler should be used
- * for notification emissions in general.
- *
- * @example <caption>Ensure values in subscribe are called just before browser repaint.</caption>
- * const intervals = Rx.Observable.interval(10); // Intervals are scheduled
- * // with async scheduler by default...
- *
- * intervals
- * .observeOn(Rx.Scheduler.animationFrame) // ...but we will observe on animationFrame
- * .subscribe(val => { // scheduler to ensure smooth animation.
- * someDiv.style.height = val + 'px';
- * });
- *
- * @see {@link delay}
- *
- * @param {IScheduler} scheduler Scheduler that will be used to reschedule notifications from source Observable.
- * @param {number} [delay] Number of milliseconds that states with what delay every notification should be rescheduled.
- * @return {Observable<T>} Observable that emits the same notifications as the source Observable,
- * but with provided scheduler.
- *
- * @method observeOn
- * @owner Observable
- */
- function observeOn(scheduler, delay) {
- if (delay === void 0) { delay = 0; }
- return function observeOnOperatorFunction(source) {
- return source.lift(new ObserveOnOperator(scheduler, delay));
- };
- }
- exports.observeOn = observeOn;
- var ObserveOnOperator = (function () {
- function ObserveOnOperator(scheduler, delay) {
- if (delay === void 0) { delay = 0; }
- this.scheduler = scheduler;
- this.delay = delay;
- }
- ObserveOnOperator.prototype.call = function (subscriber, source) {
- return source.subscribe(new ObserveOnSubscriber(subscriber, this.scheduler, this.delay));
- };
- return ObserveOnOperator;
- }());
- exports.ObserveOnOperator = ObserveOnOperator;
- /**
- * We need this JSDoc comment for affecting ESDoc.
- * @ignore
- * @extends {Ignored}
- */
- var ObserveOnSubscriber = (function (_super) {
- __extends(ObserveOnSubscriber, _super);
- function ObserveOnSubscriber(destination, scheduler, delay) {
- if (delay === void 0) { delay = 0; }
- _super.call(this, destination);
- this.scheduler = scheduler;
- this.delay = delay;
- }
- ObserveOnSubscriber.dispatch = function (arg) {
- var notification = arg.notification, destination = arg.destination;
- notification.observe(destination);
- this.unsubscribe();
- };
- ObserveOnSubscriber.prototype.scheduleMessage = function (notification) {
- this.add(this.scheduler.schedule(ObserveOnSubscriber.dispatch, this.delay, new ObserveOnMessage(notification, this.destination)));
- };
- ObserveOnSubscriber.prototype._next = function (value) {
- this.scheduleMessage(Notification_1.Notification.createNext(value));
- };
- ObserveOnSubscriber.prototype._error = function (err) {
- this.scheduleMessage(Notification_1.Notification.createError(err));
- };
- ObserveOnSubscriber.prototype._complete = function () {
- this.scheduleMessage(Notification_1.Notification.createComplete());
- };
- return ObserveOnSubscriber;
- }(Subscriber_1.Subscriber));
- exports.ObserveOnSubscriber = ObserveOnSubscriber;
- var ObserveOnMessage = (function () {
- function ObserveOnMessage(notification, destination) {
- this.notification = notification;
- this.destination = destination;
- }
- return ObserveOnMessage;
- }());
- exports.ObserveOnMessage = ObserveOnMessage;
- //# sourceMappingURL=observeOn.js.map
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