Apps Problem to get arrow keys in Javascript

[jia2001]

It can't get the arrow keys with the following javascript in Browser in Android. But it works in Chrome on PC. if anyone has a solution? many thanks.


<style>
tr.highlight{
background:#08246B;
color:white;
}
</style>
<table border="1" width="70%" id="ice">
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
<tr><td>123</td>
<td>234</td>
<td>abc</td>
<td>def</td></tr>
</table>

<script language="javascript">
<!--
var currentLine = -1;
document.onkeydown = function (e)
{
e = window.event || e;
switch (e.keyCode)
{
case 38:
currentLine--;
changeItem();
break;
case 40:
currentLine++;
changeItem();
break;
default :
break;
}
}

function changeItem()
{
if( document.all )
var it = document.getElementById("ice").children[0];
else
var it = document.getElementById("ice");
for (i=0;i<it.rows.length;i++)
{
it.rows.className = "";
}
if (currentLine < 0)
currentLine = it.rows.length - 1;
if (currentLine == it.rows.length)
currentLine = 0;
it.rows[currentLine].className = "highlight";
}

//-->
</script>