vt-social/app/javascript/mastodon/utils/scrollbar.js

37 lines
840 B
JavaScript

import { isMobile } from '../is_mobile';
/** @type {number | null} */
let cachedScrollbarWidth = null;
/**
* @return {number}
*/
const getActualScrollbarWidth = () => {
const outer = document.createElement('div');
outer.style.visibility = 'hidden';
outer.style.overflow = 'scroll';
document.body.appendChild(outer);
const inner = document.createElement('div');
outer.appendChild(inner);
const scrollbarWidth = outer.offsetWidth - inner.offsetWidth;
outer.parentNode.removeChild(outer);
return scrollbarWidth;
};
/**
* @return {number}
*/
export const getScrollbarWidth = () => {
if (cachedScrollbarWidth !== null) {
return cachedScrollbarWidth;
}
const scrollbarWidth = isMobile(window.innerWidth) ? 0 : getActualScrollbarWidth();
cachedScrollbarWidth = scrollbarWidth;
return scrollbarWidth;
};