/**
* Renders header of the column
*
* @return string
*/
public function renderHeader()
{
if ($this->getColumn()->getHeader()) {
return parent::renderHeader();
}
$checked = '';
if ($filter = $this->getColumn()->getFilter()) {
$checked = $filter->getValue() ? ' checked="checked"' : '';
}
$disabled = '';
if ($this->getColumn()->getDisabled()) {
$disabled = ' disabled="disabled"';
}
$html = '<input type="checkbox" ';
$html .= 'name="' . $this->getColumn()->getFieldName() . '" ';
$html .= 'onclick="' . $this->getColumn()->getGrid()->getJsObjectName() . '.checkCheckboxes(this)" ';
$html .= 'class="checkbox"' . $checked . $disabled . ' ';
$html .= 'title="' . Mage::helper('Mage_Backend_Helper_Data')->__('Select All') . '"/>';
return $html;
}
