To freeze a specified row on top of grid after sorting the grid, please move that row to first position in 'onSortColumn' event handler.
<script>
function onSortColumn(){
var dg = $(this);
var index = -1;
var rows = dg.datagrid('getRows');
for(var i=0; i<rows.length; i++){
var row = rows[i];
if (row.itemid == 'ItemHeader'){
index = i;
break;
}
}
if (index >= 0){
var row = rows[index];
dg.datagrid('deleteRow', index);
dg.datagrid('insertRow', {
index: 0,
row: row
});
dg.datagrid('freezeRow', 0);
}
}
$(function(){
$('#dg').datagrid({onSortColumn:onSortColumn});
});
</script>