AsyncScheduler.tsā¢1.32 kB
import { Scheduler } from '../Scheduler';
import { Action } from './Action';
import { AsyncAction } from './AsyncAction';
import { TimerHandle } from './timerHandle';
export class AsyncScheduler extends Scheduler {
public actions: Array<AsyncAction<any>> = [];
/**
* A flag to indicate whether the Scheduler is currently executing a batch of
* queued actions.
* @internal
*/
public _active: boolean = false;
/**
* An internal ID used to track the latest asynchronous task such as those
* coming from `setTimeout`, `setInterval`, `requestAnimationFrame`, and
* others.
* @internal
*/
public _scheduled: TimerHandle | undefined;
constructor(SchedulerAction: typeof Action, now: () => number = Scheduler.now) {
super(SchedulerAction, now);
}
public flush(action: AsyncAction<any>): void {
const { actions } = this;
if (this._active) {
actions.push(action);
return;
}
let error: any;
this._active = true;
do {
if ((error = action.execute(action.state, action.delay))) {
break;
}
} while ((action = actions.shift()!)); // exhaust the scheduler queue
this._active = false;
if (error) {
while ((action = actions.shift()!)) {
action.unsubscribe();
}
throw error;
}
}
}