Question

Issue
In the below code , say if i want to change the color of the cell 1 ,2 and 4 , then they change the color at different intervals. (say first 1 changes then 2 changes then 4 changes)

I want all of them (1,2 and 4) to change the color at the same time.
That will look like all (1,2 and 4) are red , then all the 3 are blue again.

Here temp_array will have the cells that i have to change the color (say temp_array will have 1,2 and 4.

 function startChangingColor()
       {
            var temp;
            for(var i=0;i<temp_array.length;i++)
            {
                temp = temp_array[i];
                intervalid[i] = setInterval( createCB(temp) ,300);
            }
        }
        function createCB( val )
        {
           return function()
           {
              changeColor( val );
           };
        }

        var flag = true; 
        function changeColor (element)
        {
            if(flag==true)
            {
                 document.getElementById(CELL+element).className='redled';
                 flag=false;
            }
            else if (flag==false)
            {
                 document.getElementById(CELL+element).className='grayled';
                flag = true;
            }
        }

Answer 1

Don’t know if I’m reading this correctly but try this:

var
  cells = document.getElementsByTagName('td'),
  tempArray = [[0, 1, 3], [1, 2, 0]];

var createColorChanger = function (classNames, elements, elementSelection) {
  var currentIndex = 0;

  return function () {
    var className = classNames.shift(), i = 0, lim = elements.length;
    classNames.push(className);

    for (; i < lim; i += 1) {
      elements[i].className = elementSelection[currentIndex].indexOf(i) > -1 ? className : '';
    }

    currentIndex += 1;
    if (currentIndex >= elementSelection.length) {
      currentIndex = 0;
    }
  }
};

setInterval(createColorChanger(['grayled', 'redled'], cells, tempArray), 1000);

demo: http://jsfiddle.net/NZPTE/3/

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