MutationObserver wrapper to wait for the specified CSS selector
Dieses Skript sollte nicht direkt installiert werden. Es handelt sich hier um eine Bibliothek für andere Skripte, welche über folgenden Befehl in den Metadaten eines Skriptes eingebunden wird // @require https://update.greasyfork.org/scripts/12228/175122/setMutationHandler.js
// ==UserScript==
// @name setMutationHandler
// @description MutationObserver wrapper to wait for the specified CSS selector
// @namespace wOxxOm.scripts
// @author wOxxOm
// @grant none
// @version 3.0.2
// ==/UserScript==
function setMutationHandler(target, selector, handler, options) {
// or setMutationHandler(selector, handler, options) {
// or setMutationHandler(options) {
if (typeof arguments[0] == 'string') {
options = arguments[2] || {};
handler = arguments[1];
selector = arguments[0];
target = document;
} else if (arguments.length == 1 && target && typeof target.handler == 'function') {
options = arguments[0];
handler = options.handler;
selector = options.selector;
target = options.target || document;
} else if (!(target instanceof Node)) {
throw 'Bad params for setMutationHandler.\n' +
'A: [optional Node] target, [String] selector, [Function] handler, [optional Object] options\n' +
'B: [Object] options\n' +
'Options: target, selector, handler, processExisting, childList, attributes, characterData, subtree, attributeOldValue, characterDataOldValue, attributeFilter';
} else
options = options || {};
if (options.processExisting && target.querySelector(selector))
handler.call(null, Array.prototype.slice.call(target.querySelectorAll(selector)));
if (!options.attributes && !options.characterData && !options.childList && options.subtree === undefined)
options.childList = options.subtree = true;
var cb;
if (/^#[\w\d-]+$/.test(selector)) {
selector = selector.substr(1);
cb = MOhandlerForId;
} else {
cb = MOhandler;
}
var observer = new MutationObserver(cb);
observer.observe(target, options || {subtree:true, childList:true});
return observer;
function MOhandler(mutations) {
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 (handler.call(observer, found) === false)
observer.disconnect();
}
function MOhandlerForId(mutations) {
var el = document.getElementById(selector);
if (el && target.contains(el))
if (handler.call(observer, [el]) === false)
observer.disconnect();
}
}