tweb/src/components/lazyLoadQueueRepeat.ts

65 lines
1.7 KiB
TypeScript

/*
* https://github.com/morethanwords/tweb
* Copyright (C) 2019-2021 Eduard Kuzmenko
* https://github.com/morethanwords/tweb/blob/master/LICENSE
*/
import indexOfAndSplice from '../helpers/array/indexOfAndSplice';
import LazyLoadQueueIntersector, {LazyLoadElement} from './lazyLoadQueueIntersector';
import VisibilityIntersector, {OnVisibilityChange} from './visibilityIntersector';
export default class LazyLoadQueueRepeat extends LazyLoadQueueIntersector {
private elementsMap: Map<HTMLElement, LazyLoadElement> = new Map();
constructor(
parallelLimit?: number,
protected onVisibilityChange?: OnVisibilityChange,
options?: IntersectionObserverInit
) {
super(parallelLimit);
this.intersector = new VisibilityIntersector((item) => {
const {target, visible} = item;
const queueItem = this.elementsMap.get(target);
queueItem.visible = visible;
if(visible) {
queueItem.wasSeen = true;
if(!this.queue.includes(queueItem)) {
this.queue.push(queueItem);
}
} else {
indexOfAndSplice(this.queue, queueItem);
}
this.onVisibilityChange?.(item);
this.setProcessQueueTimeout();
}, options);
}
public clear() {
super.clear();
this.elementsMap.clear();
}
/* public async processItem(item: LazyLoadElement) {
//await super.processItem(item);
await LazyLoadQueueBase.prototype.processItem.call(this, item);
if(this.lazyLoadMedia.length) {
this.processQueue();
}
} */
public observe(el: LazyLoadElement) {
this.elementsMap.set(el.div, el);
super.observe(el);
}
public unobserve(el: LazyLoadElement) {
this.elementsMap.delete(el.div);
super.unobserve(el);
}
}