MutationObserver wrapper to wait for the specified CSS selector
Verzia zo dňa
Tento skript by nemal byť nainštalovaný priamo. Je to knižnica pre ďalšie skripty, ktorú by mali používať cez meta príkaz // @require https://update.greasyfork.org/scripts/12228/174273/setMutationHandler.js
/* EXAMPLE:
setMutationHandler(document, '.container p.some-child', function(nodes) {
// single node:
nodes[0].remove();
// or multiple nodes:
nodes.forEach(node => node.style.display = 'none');
// disconnect the observer, this is useful for one-time jobs
return false;
});
// the observation target parameter may be omitted so "document" will be used by default:
// setMutationHandler('#some-id', function(nodes) { ....... });
*/
// ==UserScript==
// @name setMutationHandler
// @description MutationObserver wrapper to wait for the specified CSS selector
// @namespace wOxxOm.scripts
// @author wOxxOm
// @grant none
// @version 2.1.1
// ==/UserScript==
function setMutationHandler(baseNode, selector, cb, options) {
if (typeof baseNode == 'string') {
options = cb;
cb = selector;
selector = baseNode;
baseNode = document;
}
var ob;
if (/^#[\w\d-]+$/.test(selector)) {
selector = selector.substr(1);
ob = new MutationObserver(MOhandlerForId);
} else {
ob = new MutationObserver(MOhandler);
}
ob.observe(baseNode || document, options || {subtree:true, childList:true});
return ob;
function MOhandler(mutations, observer) {
if (mutations.length > 100 && !document.querySelector(selector))
return;
var found = [];
for (var i=0, m; (m = mutations[i++]); ) {
switch (m.type) {
case 'childList':
var nodes = m.addedNodes, nl = nodes.length;
var textNodesOnly = true;
for (var j=0; j < nl; j++) {
var n = nodes[j];
textNodesOnly &= n.nodeType == 3; // TEXT_NODE
if (n.nodeType != 1) // ELEMENT_NODE
continue;
if (n.matches(selector))
found.push(n);
else if (n.querySelector(selector)) {
n = n.querySelectorAll(selector);
if (n.length < 1000)
found.push.apply(found, n);
else
found = found.concat(found.slice.call(n));
}
}
if (textNodesOnly && m.target.matches(selector))
found.push(m.target);
break;
case 'attributes':
if (m.target.matches(selector))
found.push(m.target);
break;
case 'characterData':
if (m.target.parentNode && m.target.parentNode.matches(selector))
found.push(m.target.parentNode);
break;
}
}
if (!found.length)
return;
if (cb.call(ob, found) === false)
ob.disconnect();
}
function MOhandlerForId(mutations, observer) {
var el = document.getElementById(selector);
if (!el || !baseNode.contains(el))
return;
if (cb.call(ob, [el]) === false)
ob.disconnect();
}
}