Untitled

Use a widget in a statically-called method
$this->widget('zii.widgets.grid.CGridView', array(
    'dataProvider' => $model->search(),
    'columns' => array(
        array(
            'name' => 'attrName',
            'value' => '--USE WIDGET HERE--',
        ),
    )
));

$this->widget('zii.widgets.grid.CGridView', array(
    'dataProvider' => $model->search(),
    'columns' => array(
        array(
            'name' => 'attrName',
            'value' => function ($data, $row, $column) {
                $controller = $column->grid->owner;
                $controller->widget(/* ... etc ... */);
            },
        ),
   )
));