要素がDOMに出現するまで待つユーティリティです。
Questo script non dovrebbe essere installato direttamente. È una libreria per altri script da includere con la chiave // @require https://update.greasyfork.org/scripts/443087/1038171/wait-for-selector.js
// ==UserScript==
// @name wait-for-selector
// @namespace http://tampermonkey.net/
// @version 1.0.0
// @license MIT
// @description 要素がDOMに出現するまで待つユーティリティです。
// @author You
// @grant none
// ==/UserScript==
'use strict'
/**
* @param {string} selectors
* @param {number} [timeout=Infinity]
* @param {ParentNode} [context=document.body]
* @returns {Promise<Element>}
*/
const waitForSelector = (selectors, timeout = Infinity, context = document.body) => {
const element = context.querySelector(selectors)
if (element) {
return Promise.resolve(element)
}
return new Promise((resolve, reject) => {
const observer = new MutationObserver(records => {
for (const { addedNodes } of records) {
if (!addedNodes.length) {
continue
}
const element = context.querySelector(selectors)
if (!element) {
continue
}
observer.disconnect()
resolve(element)
}
})
observer.observe(context, {
childList: true,
subtree: true
})
if (Number.isFinite(timeout)) {
setTimeout(() => {
observer.disconnect()
reject(new Error('Element not found'))
}, timeout)
}
})
}
unsafeWindow.waitForSelector = waitForSelector