/*
   New Perspectives on JavaScript, 2nd Edition
   Tutorial 4
   Case Problem 1

   Author:  Trent Herrring  
   Date:    03-05-2011  

   Filename:  jemenus.js

   -------------------------------------------------------------
   Function List:
   setTabs()
      Initializes the contents of the printer.htm Web page, locating
      the tab menus and assigning event handler to the tabs.

   showTab()
      Shows the currently-select tab menu, bring it to the top
      of the stack


   -------------------------------------------------------------
   Global Variable List:

   currentTab
      An object variable pointing to the currently selected tab
   
   maxZ
      A variable containing maximum z-index value among the tab lists

   -------------------------------------------------------------
*/

var currentTab = null;
var maxZ = 1;



function showTab() {
   currentTab.style.backgroundColor = "#FFFFFF";
   maxZ++;
   tabList = this.getElementsByTagName("ul")[0];
   tabList.style.zIndex = maxZ;
   currentTab = this;
   currentTab.style.backgroundColor = "rgb(221, 221, 255)";
}

function setTabs() {
var menuTabs = new Array();
var allElems = document.getElementsByTagName("*")
for(var i = 0; i < allElems.length; i++){
if(allElems.className == 'tab'){
menuTabs.push(allElems[i]);
}
}
currentTab = menuTabs[0];
for(var a = 0; a < menuTabs.length; a++){
menuTabs[a].onclick = showTab;
} 
  
}