Export Sigma Ajax Grid's data to XLS, XML and CSV

Question

Hi,

I'm using the Sigma Ajax Grid...

When I click in the pdf export button, in PHP, I can access $POST['_gt_html'] with the grid content:

Array
(
    [__gt_html] => <style type="text/css">

</style>
<table id="grid" class="gt-table" cellspacing="0"  cellpadding="0" border="0" ><!-- gt : head start  --><tr class="gt-hd-row"><td class="gt-col-grid-model"><div class="gt-inner gt-inner-left" unselectable="on" title="Modelo"><span>Modelo</span><div class="gt-hd-tool"><span class="gt-hd-icon"></span><span class="gt-hd-button"></span><span class="gt-hd-split" style="cursor: col-resize;"></span></div></div></td><td class="gt-col-grid-qty"><div class="gt-inner gt-inner-left" unselectable="on" title="Quantidade"><span>Quantidade</span><div class="gt-hd-tool"><span class="gt-hd-icon"></span><span class="gt-hd-button"></span><span class="gt-hd-split" style="cursor: col-resize;"></span></div></div></td><td class="gt-col-grid-price"><div class="gt-inner gt-inner-left" unselectable="on" title="Preço"><span>Preço</span><div class="gt-hd-tool"><span class="gt-hd-icon"></span><span class="gt-hd-button"></span><span class="gt-hd-split" style="cursor: col-resize;"></span></div></div></td></tr><!-- gt : head end  --><tbody><tr class="gt-row gt-row-even" __gt_ds_index__="0"  id="" ><td  class="gt-col-grid-model" ><div class="gt-inner  gt-inner-left " >LG</div></td><td  class="gt-col-grid-qty" ><div class="gt-inner  gt-inner-left " >1</div></td><td  class="gt-col-grid-price" ><div class="gt-inner  gt-inner-left " >3500.00</div></td></tr>
<tr class="gt-row" __gt_ds_index__="1"  id="" ><td  class="gt-col-grid-model" ><div class="gt-inner  gt-inner-left " >Philips</div></td><td  class="gt-col-grid-qty" ><div class="gt-inner  gt-inner-left " >3</div></td><td  class="gt-col-grid-price" ><div class="gt-inner  gt-inner-left " >3200.00</div></td></tr>
<tr class="gt-row gt-row-even" __gt_ds_index__="2"  id="" ><td  class="gt-col-grid-model" ><div class="gt-inner  gt-inner-left " >Sony</div></td><td  class="gt-col-grid-qty" ><div class="gt-inner  gt-inner-left " >3</div></td><td  class="gt-col-grid-price" ><div class="gt-inner  gt-inner-left " >4500.00</div></td></tr>
<tr class="gt-row" __gt_ds_index__="3"  id="" ><td  class="gt-col-grid-model" ><div class="gt-inner  gt-inner-left " >Toshiba</div></td><td  class="gt-col-grid-qty" ><div class="gt-inner  gt-inner-left " >2</div></td><td  class="gt-col-grid-price" ><div class="gt-inner  gt-inner-left " >4200.00</div></td></tr>
</tbody></table>
)

But when I click in csv, xml or xls export button, $POST['_gt_html'] doesn't exist. There is only $_POST['_gt_json'] position without the visible grid data:

Array
(
    [_gt_json] => {"recordType":"object","pageInfo":{"pageSize":20,"pageNum":1,"totalRowNum":4,"totalPageNum":1,"startRowNum":1,"endRowNum":4},"columnInfo":[{"id":"model","header":"Modelo","fieldName":"model","fieldIndex":"model","sortOrder":null,"hidden":false,"exportable":true,"printable":true},{"id":"qty","header":"Quantidade","fieldName":"qty","fieldIndex":"qty","sortOrder":null,"hidden":false,"exportable":true,"printable":true},{"id":"price","header":"Preço","fieldName":"price","fieldIndex":"price","sortOrder":null,"hidden":false,"exportable":true,"printable":true}],"sortInfo":[],"filterInfo":[],"parameters":{},"action":"export","exportType":"xls","exportFileName":null}
)

How do I get the visible grid data to export as csv, xml or xls? Thank you.