// Splintered striper 1.3

// reworking of Zebra Tables and similar methods which works not only for tables and even/odd rows,

// but as a general DOM means of assigning any number of classes to children of a parent element.

// Patrick H. Lauke aka redux / www.splintered.co.uk

// Distributed under the Creative Commons Attribution-ShareAlike license - http://creativecommons.org/licenses/by-sa/2.0/




/*

 * Summary:      Core experiment function that applies any number of classes to all child elements

 *               contained in all occurences of a parent element (either with or without a specific class)

 * Parameters:   parentElementTag - parent tag name

 *               parentElementClass - class assigned to the parent; if null, all parentElementTag elements will be affected

 *               childElementTag -  tag name of the child elements to apply the styles to

 *               styleClasses - comma separated list of any number of style classes (using 2 classes gives the classic "zebra" effect)

 * Return:       none

 */


function striper(parentElementTag, parentElementClass, childElementTag, styleClasses)

{

	var i=0,currentParent,currentChild;

	// capability and sanity check

	if ((document.getElementsByTagName)&&(parentElementTag)&&(childElementTag)&&(styleClasses)) {

		// turn the comma separate list of classes into an array

		var styles = styleClasses.split(',');

		// get an array of all parent tags

		var parentItems = document.getElementsByTagName(parentElementTag);

		// loop through all parent elements

		while (currentParent = parentItems[i++]) {

			// if parentElementClass was null, or if the current parent's class matches the specified class

			if ((parentElementClass == null)||(currentParent.className == parentElementClass)) {

				var j=0,k=0;

				// get all child elements in the current parent element

				var childItems = currentParent.getElementsByTagName(childElementTag);

				// loop through all child elements

				while (currentChild = childItems[j++]) {

					// based on the current element and the number of styles in the array, work out which class to apply

					k = (j+(styles.length-1)) % styles.length;

					// add the class to the child element - if any other classes were already present, they're kept intact

					currentChild.className = currentChild.className+" "+styles[k];

				}

			}

		}

	}

}