Question

I’m writing a JavaSCript class that has a method that recursively calls itself.

Scheduler.prototype.updateTimer = function () {     document.write( this._currentTime );     this._currentTime -= 1000;     // recursively calls itself     this._updateUITimerHandler = window.setTimeout( arguments.callee , 1000 ); } 

Property description:

_currentTime: the currentTime of the timer in miliseconds. _updateUITimerHandler: stores the reference so can be used later with clearTimeout(). 

my problem is where I’m using recursion with setTimeout(). I know setTimeout() will accept some string to execute, or a reference to a function. since this function is method of an object, I don’t know how to call it from outside. so I used the second format of setTimeout() and passed in a reference to the method itself. but it does not work.

Answer 1

Try this:-

Scheduler.prototype.startTimer = function() {   var self = this;   function updateTimer() {     this._currentTime -= 1000;     self.hTimer = window.setTimeout(updateTimer, 1000)     self.tick()   }   this.hTimer = window.setTimeout(updateTimer, 1000) } Scheduler.prototype.stopTimer = function() {     if (this.hTimer != null) window.clearTimeout(this.hTimer)   this.hTimer = null; } Scheduler.prototype.tick = function() {   //Do stuff on timer update }