how can i create custom grid column with radio button in custom module in magento

Question

i want to create custom grid column with radio button in it. i have created with following code,but the problem is,i am not getting radio button name thats why radio button can be selected to multiple.....help me to get radio button name.

protected function _prepareColumns()<br/>
    { 
$this->addColumn('pr_id',<br/>
            array( <br/>
                'header'=> Mage::helper('catalog')->__('p_id'),<br/>
                'index' => 'entity_id',<br/>
         'type' => 'radio',<br/>
         'name' => 'prid',<br/>
         'width' => '50px',<br/>

    ));

........

please help me

Answer 1

$this->addColumn('pr_id', array(
        'header'    => Mage::helper('adminhtml')->__('p_id'),
        'type'      => 'radio',
        'html_name' => 'prid[]',
        'align'     => 'center',
        'value'    => array('1')
    ));