Magento 1.9,我无法获得选中产品的网格

Magento 1.9,i can't get grid with checked products

我创建了一个自定义模块,我在我的模块的管理中使用了网格产品。当我检查产品时,我可以成功地将它们保存到我的 table,但我想让这个产品加载选中的行。

我该怎么做?

这是我的代码:

$this->addColumn('is_selected', array(
        'type'      => 'checkbox',
        'name'      => 'is_selected',
        'field_name' => 'selectedproducts[]',
        'values' => $this->_getSelectedProducts(),//here i go to method
        'index'     => 'entity_id',
    ));

下面是

protected function _getSelectedProducts()
    {
        $products = Mage::getModel('custom_module/mytable')->getData();//Here i need some help 
        return $products;
    }

这是带有序列化器的网格的解决方案:

        protected function _getSelectedProducts(){
            $products = $this->getActionProducts();
            if (!is_array($products)) {
                $products = array_keys($this->getSelectedProducts());
            }
            return $products;
        }
        //callback method for serializer
        public function getSelectedProducts() {
            $products = array();
            $selected = $this->getRequest()->getPost('products');
            if (!is_array($selected)){
                $selected = array();
            }
            foreach ($selected as $product) {
                $products[$product->getId()] = array('position' => 
                $product->getPosition());
            }
            return $products;
        }