[6a3a178] | 1 | import { Operator } from '../Operator';
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| 2 | import { Subscriber } from '../Subscriber';
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| 3 | import { Notification } from '../Notification';
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| 4 | import { MonoTypeOperatorFunction, PartialObserver, SchedulerAction, SchedulerLike, TeardownLogic } from '../types';
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| 5 | /**
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| 6 | *
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| 7 | * Re-emits all notifications from source Observable with specified scheduler.
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| 8 | *
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| 9 | * <span class="informal">Ensure a specific scheduler is used, from outside of an Observable.</span>
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| 10 | *
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| 11 | * `observeOn` is an operator that accepts a scheduler as a first parameter, which will be used to reschedule
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| 12 | * notifications emitted by the source Observable. It might be useful, if you do not have control over
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| 13 | * internal scheduler of a given Observable, but want to control when its values are emitted nevertheless.
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| 14 | *
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| 15 | * Returned Observable emits the same notifications (nexted values, complete and error events) as the source Observable,
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| 16 | * but rescheduled with provided scheduler. Note that this doesn't mean that source Observables internal
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| 17 | * scheduler will be replaced in any way. Original scheduler still will be used, but when the source Observable emits
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| 18 | * notification, it will be immediately scheduled again - this time with scheduler passed to `observeOn`.
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| 19 | * An anti-pattern would be calling `observeOn` on Observable that emits lots of values synchronously, to split
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| 20 | * that emissions into asynchronous chunks. For this to happen, scheduler would have to be passed into the source
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| 21 | * Observable directly (usually into the operator that creates it). `observeOn` simply delays notifications a
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| 22 | * little bit more, to ensure that they are emitted at expected moments.
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| 23 | *
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| 24 | * As a matter of fact, `observeOn` accepts second parameter, which specifies in milliseconds with what delay notifications
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| 25 | * will be emitted. The main difference between {@link delay} operator and `observeOn` is that `observeOn`
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| 26 | * will delay all notifications - including error notifications - while `delay` will pass through error
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| 27 | * from source Observable immediately when it is emitted. In general it is highly recommended to use `delay` operator
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| 28 | * for any kind of delaying of values in the stream, while using `observeOn` to specify which scheduler should be used
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| 29 | * for notification emissions in general.
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| 30 | *
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| 31 | * ## Example
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| 32 | * Ensure values in subscribe are called just before browser repaint.
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| 33 | * ```ts
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| 34 | * import { interval } from 'rxjs';
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| 35 | * import { observeOn } from 'rxjs/operators';
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| 36 | *
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| 37 | * const intervals = interval(10); // Intervals are scheduled
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| 38 | * // with async scheduler by default...
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| 39 | * intervals.pipe(
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| 40 | * observeOn(animationFrameScheduler), // ...but we will observe on animationFrame
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| 41 | * ) // scheduler to ensure smooth animation.
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| 42 | * .subscribe(val => {
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| 43 | * someDiv.style.height = val + 'px';
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| 44 | * });
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| 45 | * ```
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| 46 | *
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| 47 | * @see {@link delay}
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| 48 | *
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| 49 | * @param {SchedulerLike} scheduler Scheduler that will be used to reschedule notifications from source Observable.
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| 50 | * @param {number} [delay] Number of milliseconds that states with what delay every notification should be rescheduled.
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| 51 | * @return {Observable<T>} Observable that emits the same notifications as the source Observable,
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| 52 | * but with provided scheduler.
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| 53 | *
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| 54 | * @method observeOn
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| 55 | * @owner Observable
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| 56 | */
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| 57 | export declare function observeOn<T>(scheduler: SchedulerLike, delay?: number): MonoTypeOperatorFunction<T>;
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| 58 | export declare class ObserveOnOperator<T> implements Operator<T, T> {
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| 59 | private scheduler;
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| 60 | private delay;
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| 61 | constructor(scheduler: SchedulerLike, delay?: number);
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| 62 | call(subscriber: Subscriber<T>, source: any): TeardownLogic;
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| 63 | }
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| 64 | /**
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| 65 | * We need this JSDoc comment for affecting ESDoc.
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| 66 | * @ignore
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| 67 | * @extends {Ignored}
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| 68 | */
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| 69 | export declare class ObserveOnSubscriber<T> extends Subscriber<T> {
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| 70 | private scheduler;
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| 71 | private delay;
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| 72 | /** @nocollapse */
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| 73 | static dispatch(this: SchedulerAction<ObserveOnMessage>, arg: ObserveOnMessage): void;
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| 74 | constructor(destination: Subscriber<T>, scheduler: SchedulerLike, delay?: number);
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| 75 | private scheduleMessage;
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| 76 | protected _next(value: T): void;
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| 77 | protected _error(err: any): void;
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| 78 | protected _complete(): void;
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| 79 | }
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| 80 | export declare class ObserveOnMessage {
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| 81 | notification: Notification<any>;
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| 82 | destination: PartialObserver<any>;
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| 83 | constructor(notification: Notification<any>, destination: PartialObserver<any>);
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| 84 | }
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