CGridview displays existent rows of the table (using DataProvider)

How to add new records through cgridview ?

Suppose you have Categories and Products (category has many products - see the below related wiki) http://www.yiiframework.com/wiki/681/update-related-models-of-a-model-using-listbox-and-checkboxlist-in-the-form/

we want to display all related products with a specific category and the last cgridview row as editable that we send it as new record, so how to do that ?

In your view Category (_form.php)

<h2>Related Products</h2>
    <?php
    $rels = new CArrayDataProvider($model->relatedProducts);

    $data = CHtml::listData($model->relatedProducts,'id','title');
    $listBox = CHtml::dropDownList('newRelProduct', null, $data);
    $buttonPlus = CHtml::ajaxLink('add new record', $this->createUrl('addRelProduct'), [
                'type' => 'POST',
                'data' => array('cid' => $model->id, 'pid' => 'js:$("#newRelProduct").val()'),
                'success' => 'function(html){  $.fn.yiiGridView.update("grid-related-products"); }'
    ]);


    $this->widget('zii.widgets.grid.CGridView', array(
        'dataProvider' => $rels,
        'id' => 'grid-related-products',
        'columns' => array(
            [
                'name' => 'Title',
                'header' => 'Product',
                'footer' => $listBox,
            ],
            [
                'class' => 'CButtonColumn',
                'template' => '{delete}',
                'buttons' => ['delete' => ['url' => '$this->grid->Controller->createUrl("deleteRelProd",["pid"=>$data->id])']],
                'footer' => $buttonPlus,
            ],
        ),
    ));
    

In your Category controller

public function actionAddRelProduct() {

        $cid = Yii::app()->request->getParam('cid');
        $pid = Yii::app()->request->getParam('pid');

        $p = Products::model()->findByPk($pid);
        $c = Category::model()->findByPk($cid);
        
        if ($p && $c) {
                $p->category_id = $cid;
                if ($p->save())
                    echo 'ok';
                else
                    echo 'error save';
            }
         
    }
    
    public function actionDeleteRelProdt() {
        $pid = Yii::app()->request->getParam('pid');
        $p = Products::model()->findByPk($pid);
        if ($p) {
                $p->category_id = null;
                if ($p->save())
                    echo 'ok';
                else
                    echo 'error save';
        }
    }