www.gusucode.com > 一个基于extjs的强大聊天插件源码程序 > 一个基于extjs的强大聊天插件/extjame/ext-jame/js/ext2/source/util/TaskMgr.js
/* * Ext JS Library 2.0.2 * Copyright(c) 2006-2008, Ext JS, LLC. * licensing@extjs.com * * http://extjs.com/license */ /** * @class Ext.util.TaskRunner * Provides the ability to execute one or more arbitrary tasks in a multithreaded manner. Generally, you can use * the singleton {@link Ext.TaskMgr} instead, but if needed, you can create separate instances of TaskRunner. Any * number of separate tasks can be started at any time and will run independently of each other. Example usage: * <pre><code> // Start a simple clock task that updates a div once per second var task = { run: function(){ Ext.fly('clock').update(new Date().format('g:i:s A')); }, interval: 1000 //1 second } var runner = new Ext.util.TaskRunner(); runner.start(task); </code></pre> * @constructor * @param {Number} interval (optional) The minimum precision in milliseconds supported by this TaskRunner instance * (defaults to 10) */ Ext.util.TaskRunner = function(interval){ interval = interval || 10; var tasks = [], removeQueue = []; var id = 0; var running = false; // private var stopThread = function(){ running = false; clearInterval(id); id = 0; }; // private var startThread = function(){ if(!running){ running = true; id = setInterval(runTasks, interval); } }; // private var removeTask = function(t){ removeQueue.push(t); if(t.onStop){ t.onStop.apply(t.scope || t); } }; // private var runTasks = function(){ if(removeQueue.length > 0){ for(var i = 0, len = removeQueue.length; i < len; i++){ tasks.remove(removeQueue[i]); } removeQueue = []; if(tasks.length < 1){ stopThread(); return; } } var now = new Date().getTime(); for(var i = 0, len = tasks.length; i < len; ++i){ var t = tasks[i]; var itime = now - t.taskRunTime; if(t.interval <= itime){ var rt = t.run.apply(t.scope || t, t.args || [++t.taskRunCount]); t.taskRunTime = now; if(rt === false || t.taskRunCount === t.repeat){ removeTask(t); return; } } if(t.duration && t.duration <= (now - t.taskStartTime)){ removeTask(t); } } }; /** * Starts a new task. * @param {Object} task A config object that supports the following properties:<ul> * <li><code>run</code> : Function<div class="sub-desc">The function to execute each time the task is run. The * function will be called at each interval and passed the <code>args</code> argument if specified. If a * particular scope is required, be sure to specify it using the <code>scope</scope> argument.</div></li> * <li><code>interval</code> : Number<div class="sub-desc">The frequency in milliseconds with which the task * should be executed.</div></li> * <li><code>args</code> : Array<div class="sub-desc">(optional) An array of arguments to be passed to the function * specified by <code>run</code>.</div></li> * <li><code>scope</code> : Object<div class="sub-desc">(optional) The scope in which to execute the * <code>run</code> function.</div></li> * <li><code>duration</code> : Number<div class="sub-desc">(optional) The length of time in milliseconds to execute * the task before stopping automatically (defaults to indefinite).</div></li> * <li><code>repeat</code> : Number<div class="sub-desc">(optional) The number of times to execute the task before * stopping automatically (defaults to indefinite).</div></li> * </ul> * @return {Object} The task */ this.start = function(task){ tasks.push(task); task.taskStartTime = new Date().getTime(); task.taskRunTime = 0; task.taskRunCount = 0; startThread(); return task; }; /** * Stops an existing running task. * @param {Object} task The task to stop * @return {Object} The task */ this.stop = function(task){ removeTask(task); return task; }; /** * Stops all tasks that are currently running. */ this.stopAll = function(){ stopThread(); for(var i = 0, len = tasks.length; i < len; i++){ if(tasks[i].onStop){ tasks[i].onStop(); } } tasks = []; removeQueue = []; }; }; /** * @class Ext.TaskMgr * A static {@link Ext.util.TaskRunner} instance that can be used to start and stop arbitrary tasks. See * {@link Ext.util.TaskRunner} for supported methods and task config properties. * <pre><code> // Start a simple clock task that updates a div once per second var task = { run: function(){ Ext.fly('clock').update(new Date().format('g:i:s A')); }, interval: 1000 //1 second } Ext.TaskMgr.start(task); </code></pre> * @singleton */ Ext.TaskMgr = new Ext.util.TaskRunner();