EXTJS4.2 时间动态刷新显示

function clockGo() {
Ext.TaskManager.start({
run: function () {
//Ext.getCmp("clock").setText(Ext.Date.format(new Date(), 'g:i:s A'));
var showtime = document.getElementById("time");
var now = new Date();
var date = now.toLocaleString();// //获取日期与时间 如 2014年6月25日 下午4:45:06
var hours = now.getHours();
var minutes = now.getMinutes();
var seconds = now.getSeconds();
if (hours < 10) hours = "0" + hours;
if (minutes < 10) minutes = "0" + minutes;
if (seconds < 10) seconds = "0" + seconds;
//var timestr = hours + ":" + minutes + ":" + seconds;
var timestr = date ;
showtime.innerHTML = timestr;
},
interval: 1000//每秒刷新一次
});
}

//顶部面板
var north = new Ext.Panel({
frame: true,
plain: true,
height: 56,
border: false,
region: 'north',
items: [{
baseCls: 'x-plain',
border: false,
height: 56,
html: " <TABLE cellSpacing=0 cellPadding=0 width=100% background='/images/header_bg.jpg' border=0> <TR height=56><TD width=260><IMG height=56 src='/images/header_left.jpg' width=260></TD><TD style='FONT-WEIGHT: bold; COLOR: #fff; PADDING-TOP: 20px' align=right>当前时间：<span id=time></span>  </div>当前用户：admin    <A style='COLOR: #fff' href=''>修改口令</A>    <A style='COLOR: #fff' onclick='if (confirm('确定要退出吗？')) return true; else return false;' href='' target=_top>退出系统</A> </TD><TD align=right width=268><IMG height=56 src='/images/header_right.jpg' width=268></TD></TR></TABLE><TABLE cellSpacing=0 cellPadding=0 width=100% border=0><TR bgColor=#1c5db6 height=4><TD></TD></TR></TABLE>"
}],
listeners: {
'render': function () {
clockGo();
}
}
});