/*-----------------------------------------------------------
 Original
 http://archiva.jp/web/javascript/tab-menu.html

 Customized by WWW WATCH
 http://hyper-text.org/archives/2007/09/javascript_tab.shtml
------------------------------------------------------------*/

/*--setup--*/
window.onload=function() {
   tab.setup = {
      tabs: document.getElementById('tab') != null ? document.getElementById('tab').getElementsByTagName('li'):'',
      pages: [
         document.getElementById('page1'),
         document.getElementById('page2'),
         document.getElementById('page3'),
         document.getElementById('page4'),
         document.getElementById('page5'),
      ]
   }
   tab.init();
}
/*--setup end--*/

var tab = {
   init: function(){
      var tabs = this.setup.tabs;
      var pages = this.setup.pages;
      
      for(i=0; i<pages.length; i++) {
         if(i !== 0 && typeof(pages[i]) != 'undefined'){ // 20090723 && ・・・typeof()条件追加
             pages[i].style.display = 'none';
         }
         if(!tabs[i]){  // 20090723 if条件追加
            return false;
         }
         if (typeof(tabs[i]) == 'undefined' && typeof(pages[i]) == 'undefined'){ // 20090723 && ・・・typeof()条件追加
            return false;
         } else {
             tabs[i].onclick = function(){ tab.showpage(this); return false; };
         }
      }
   },
   
   showpage: function(obj){
      var tabs = this.setup.tabs;
      var pages = this.setup.pages;
      var num;
      
      for(num=0; num<tabs.length; num++) {
         if(tabs[num] === obj) break;
      }
      
      for(var i=0; i<pages.length; i++) {
         if ( typeof(pages[i]) == 'undefined'){ // 20090723 if(typeof())条件追加
            return false;
         }
         if(i == num) {
            pages[num].style.display = 'block';
            tabs[num].className = 'present';
         }
         else{
            pages[i].style.display = 'none';
            tabs[i].className = null;
         }
      }
   }
}