The source code

/** - * @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: - *


-// Start a simple clock task that updates a div once per second
-var updateClock = function(){
-    Ext.fly('clock').update(new Date().format('g:i:s A'));
-} 
-var task = {
-    run: updateClock,
-    interval: 1000 //1 second
-}
-var runner = new Ext.util.TaskRunner();
-runner.start(task);
-
-// equivalent using TaskMgr
-Ext.TaskMgr.start({
-    run: updateClock,
-    interval: 1000
-});
-
- *

- *

See the {@link #start} method for details about how to configure a task object.

- * Also see {@link Ext.util.DelayedTask}. - * - * @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 = [], - id = 0, - running = false, - - // private - stopThread = function(){ - running = false; - clearInterval(id); - id = 0; - }, - - // private - startThread = function(){ - if(!running){ - running = true; - id = setInterval(runTasks, interval); - } - }, - - // private - removeTask = function(t){ - removeQueue.push(t); - if(t.onStop){ - t.onStop.apply(t.scope || t); - } - }, - - // private - runTasks = function(){ - var rqLen = removeQueue.length, - now = new Date().getTime(); - - if(rqLen > 0){ - for(var i = 0; i < rqLen; i++){ - tasks.remove(removeQueue[i]); - } - removeQueue = []; - if(tasks.length < 1){ - stopThread(); - return; - } - } - for(var i = 0, t, itime, rt, len = tasks.length; i < len; ++i){ - t = tasks[i]; - itime = now - t.taskRunTime; - if(t.interval <= itime){ - 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. - * @method start - * @param {Object} task

A config object that supports the following properties:

run : Function
The function to execute each time the task is invoked. The - * function will be called at each interval and passed the args argument if specified, and the - * current invocation count if not.
- *
If a particular scope (this reference) is required, be sure to specify it using the scope argument.
- *
Return false from this function to terminate the task.
interval : Number
The frequency in milliseconds with which the task - * should be invoked.
args : Array
(optional) An array of arguments to be passed to the function - * specified by run. If not specified, the current invocation count is passed.
scope : Object
(optional) The scope (this reference) in which to execute the - * run function. Defaults to the task config object.
duration : Number
(optional) The length of time in milliseconds to invoke - * the task before stopping automatically (defaults to indefinite).
repeat : Number
(optional) The number of times to invoke the task before - * stopping automatically (defaults to indefinite).

- *

Before each invocation, Ext injects the property taskRunCount into the task object so - * that calculations based on the repeat count can be performed.

- * @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. - * @method stop - * @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. - * @method stopAll - */ - 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 - * @extends Ext.util.TaskRunner - * 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. - *


-// 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);
-

- *

See the {@link #start} method for details about how to configure a task object.

- * @singleton - */ -Ext.TaskMgr = new Ext.util.TaskRunner();