40 lines
903 B
TypeScript
40 lines
903 B
TypeScript
import Diff from "./Diff"
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export default class InfiniteScroller {
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container: HTMLElement
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threshold: number
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constructor(container, threshold) {
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this.container = container
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this.threshold = threshold
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const check = () => {
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if(this.container.scrollTop + this.container.clientHeight >= this.container.scrollHeight - threshold) {
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this.loadMore()
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}
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}
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this.container.addEventListener("scroll", _ => {
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// Wait for mutations to finish before checking if we need infinite scroll to trigger.
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if(Diff.mutations.mutations.length > 0) {
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Diff.mutations.wait(() => check())
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return
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}
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// Otherwise, queue up the check immediately.
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// Don't call check() directly to make scrolling as smooth as possible.
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Diff.mutations.queue(check)
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})
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}
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loadMore() {
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const button = document.getElementById("load-more-button")
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if(!button) {
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return
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}
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button.click()
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}
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}
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