MutationObserver wrapper to wait for the specified CSS selector
Version vom
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/12228/174877/setMutationHandler.js
/* EXAMPLE:
setMutationHandler('.container p.some-child', nodes => {
nodes.forEach(node => node.style.display = 'none');
return false; // disconnect the observer, this is useful for one-time jobs
});
setMutationHandler({
processExisting: true,
selector: '.container p.some-child',
handler: nodes => nodes.forEach(node => node.style.display = 'none')
});
setMutationHandler({
selector: '.container p.some-child',
processExisting: false, // optional
target: document, // optional
childList: true, // optional
subtree: true, // optional
attributes: false, // optional
attributeFilter: [], // optional
attributeOldValue: false, // optional
characterData: false, // optional
characterDataOldValue: false, // optional
handler: nodes => {
nodes.forEach(node => node.style.display = 'none');
return false; // disconnect the observer, this is useful for one-time jobs
},
});
*/
// ==UserScript==
// @name setMutationHandler
// @description MutationObserver wrapper to wait for the specified CSS selector
// @namespace wOxxOm.scripts
// @author wOxxOm
// @grant none
// @version 3.0.1
// ==/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';
}
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();
}
}