waitForKeyElements utility function

A utility function for userscripts that detects and handles AJAXed content.

此腳本不應該直接安裝,它是一個供其他腳本使用的函式庫。欲使用本函式庫,請在腳本 metadata 寫上: // @require https://update.gf.qytechs.cn/scripts/446257/1059316/waitForKeyElements%20utility%20function.js

您需要先安裝使用者腳本管理器擴展,如 TampermonkeyGreasemonkeyViolentmonkey 之後才能安裝該腳本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyViolentmonkey 後才能安裝該腳本。

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyUserscripts 後才能安裝該腳本。

你需要先安裝一款使用者腳本管理器擴展,比如 Tampermonkey,才能安裝此腳本

您需要先安裝使用者腳本管理器擴充功能後才能安裝該腳本。

(我已經安裝了使用者腳本管理器,讓我安裝!)

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

(我已經安裝了使用者樣式管理器,讓我安裝!)

// ==UserScript==
// @version 1.0.0
// @name waitForKeyElements utility function
// @description A utility function for userscripts that detects and handles AJAXed content.
// @namespace https://github.com/CoeJoder/waitForKeyElements.js
// @author CoeJoder
// @homepage https://github.com/CoeJoder/waitForKeyElements.js
// @source https://raw.githubusercontent.com/CoeJoder/waitForKeyElements.js/master/waitForKeyElements.js
// 
// ==/UserScript==

/**
 * A utility function for userscripts that detects and handles AJAXed content.
 *
 * Usage example:
 *
 *     function callback(domElement) {
 *         domElement.innerHTML = "This text inserted by waitForKeyElements().";
 *     }
 * 
 *     waitForKeyElements("div.comments", callback);
 *     // or
 *     waitForKeyElements(selectorFunction, callback);
 *
 * @param {(string|function)} selectorOrFunction - The selector string or function.
 * @param {function} callback - The callback function; takes a single DOM element as parameter.
 *                              If returns true, element will be processed again on subsequent iterations.
 * @param {boolean} [waitOnce=true] - Whether to stop after the first elements are found.
 * @param {number} [interval=300] - The time (ms) to wait between iterations.
 * @param {number} [maxIntervals=-1] - The max number of intervals to run (negative number for unlimited).
 */
function waitForKeyElements(selectorOrFunction, callback, waitOnce, interval, maxIntervals) {
	if (typeof waitOnce === "undefined") {
		waitOnce = true;
	}
	if (typeof interval === "undefined") {
		interval = 300;
	}
	if (typeof maxIntervals === "undefined") {
		maxIntervals = -1;
	}
	var targetNodes = (typeof selectorOrFunction === "function")
			? selectorOrFunction()
			: document.querySelectorAll(selectorOrFunction);

	var targetsFound = targetNodes && targetNodes.length > 0;
	if (targetsFound) {
		targetNodes.forEach(function(targetNode) {
			var attrAlreadyFound = "data-userscript-alreadyFound";
			var alreadyFound = targetNode.getAttribute(attrAlreadyFound) || false;
			if (!alreadyFound) {
				var cancelFound = callback(targetNode);
				if (cancelFound) {
					targetsFound = false;
				}
				else {
					targetNode.setAttribute(attrAlreadyFound, true);
				}
			}
		});
	}

	if (maxIntervals !== 0 && !(targetsFound && waitOnce)) {
		maxIntervals -= 1;
		setTimeout(function() {
			waitForKeyElements(selectorOrFunction, callback, waitOnce, interval, maxIntervals);
		}, interval);
	}
}