// Function which swaps display between tabs
var sectionName = "C2";

function changeTab (tabID) {
if (isvalidTab(tabID))
{
    // toggle the tab images
    document.getElementById('tab_over').style.display = 'none';
    document.getElementById('tab_prereq').style.display = 'none';
    document.getElementById('tab_outline').style.display = 'none';
    document.getElementById('tab_materials').style.display = 'none';
    document.getElementById('tab_sysreqs').style.display = 'none';
    document.getElementById('tab_'+tabID).style.display = 'block';

    // toggle the divs on and off
    if (document.getElementById('tabnav_over')!=undefined)
    {document.getElementById('tabnav_over').src = '/eduapp/images/over.gif';}
    if (document.getElementById('tabnav_prereq')!=undefined)
    {document.getElementById('tabnav_prereq').src = '/eduapp/images/prereq.gif';}
    if (document.getElementById('tabnav_outline')!=undefined)
    {document.getElementById('tabnav_outline').src = '/eduapp/images/outline.gif';}
    if (document.getElementById('tabnav_materials')!=undefined)
    {document.getElementById('tabnav_materials').src = '/eduapp/images/materials.gif';}
    if (document.getElementById('tabnav_sysreqs')!=undefined)
    {document.getElementById('tabnav_sysreqs').src = '/eduapp/images/sysreqs.gif';}

    document.getElementById('tabnav_'+tabID).src = '/eduapp/images/'+tabID+'_sel.gif';
  }
}
function isvalidTab (tabID) {
  if (tabID == 'over' || tabID == 'prereq' || tabID == 'outline' || tabID == 'materials' || tabID == 'sysreqs' )  {
      return true; }
    else { return false; }
}