// delcare variables
var tabs_on = new Array();
var tabs_off = new Array();
var tabs_onoff = new Array(true,false,false,false);
var divnames = new Array('tabContents1','tabContents2','tabContents3','tabContents4');

// set image filenames 
tabs_off[0] = '/view/images/section/news_nav_1_off.gif';
tabs_off[1] = '/view/images/section/news_nav_2_off.gif';
tabs_off[2] = '/view/images/section/news_nav_3_off.gif';
tabs_off[3] = '/view/images/section/news_nav_4_off.gif';

tabs_on[0] = '/view/images/section/news_nav_1_on.gif';
tabs_on[1] = '/view/images/section/news_nav_2_on.gif';
tabs_on[2] = '/view/images/section/news_nav_3_on.gif';
tabs_on[3] = '/view/images/section/news_nav_4_on.gif';

// preload Images
var tabs_on_preload = new Array();
for (var i = 0; i < tabs_off.length; i++) {
	tabs_on_preload[i] = new Image();
	tabs_on_preload.src = tabs_on[i];
}

// function to show tab contents
function ShowTab(tab,divName) {
	document.getElementById(divName).style.display = "block";
	for (var i=0; i < divnames.length; i++) {
		if (divnames[i] != divName) document.getElementById(divnames[i]).style.display = "none";
	}
	if (tab == "tab1") { 
		document.tab1.src=tabs_on[0];
		document.tab2.src=tabs_off[1];
		document.tab3.src=tabs_off[2];
		document.tab4.src=tabs_off[3];
		tabs_onoff[0] = true;
		tabs_onoff[1] = false;
		tabs_onoff[2] = false;
		tabs_onoff[3] = false;
	}
	else if (tab == "tab2") { 
		document.tab1.src=tabs_off[0];
		document.tab2.src=tabs_on[1];
		document.tab3.src=tabs_off[2];
		document.tab4.src=tabs_off[3];
		tabs_onoff[0] = false;
		tabs_onoff[1] = true;
		tabs_onoff[2] = false;
		tabs_onoff[3] = false;
	}
	else if (tab == "tab3") { 
		document.tab1.src=tabs_off[0];
		document.tab2.src=tabs_off[1];
		document.tab3.src=tabs_on[2];
		document.tab4.src=tabs_off[3];
		tabs_onoff[0] = false;
		tabs_onoff[1] = false;
		tabs_onoff[2] = true;
		tabs_onoff[3] = false;
	}
	else if (tab == "tab4") { 
		document.tab1.src=tabs_off[0];
		document.tab2.src=tabs_off[1];
		document.tab3.src=tabs_off[2];
		document.tab4.src=tabs_on[3];
		tabs_onoff[0] = false;
		tabs_onoff[1] = false;
		tabs_onoff[2] = false;
		tabs_onoff[3] = true;;
	}
}