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Forked from jwilson8767/es6-element-ready.js
Last active November 17, 2022 11:57
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Wait for an element to exist. ES6, Promise, MutationObserver (version for userScript @require)
// MIT Licensed
// Author: jwilson8767
/**
* Waits for an element satisfying selector to exist, then resolves promise with the element.
* Useful for resolving race conditions.
*
*/
function elementReady(selector) {
return new Promise((resolve, reject) => {
let el = document.querySelector(selector);
if (el) {
resolve(el);
return
}
new MutationObserver((mutationRecords, observer) => {
// Query for elements matching the specified selector
Array.from(document.querySelectorAll(selector)).forEach((element) => {
resolve(element);
//Once we have resolved we don't need the observer anymore.
observer.disconnect();
});
})
.observe(document.documentElement, {
childList: true,
subtree: true
});
});
}
import { elementReady } from "es6-element-ready";
// Simple usage to delete an element if/when it exists:
elementReady('#someWidget').then((someWidget)=>{someWidget.remove();});
// Wait for all elements be ready
Promise.all([elementReady('#element1'), elementReady('#element2'), elementReady('.element3')]).then((matched_elements)=>{
//callback function body
})
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