Good practice is to add your own file to the lib / Varien / Data / Form / Element folder

I need to create a module in Magento that will have several database tables. One of the functions of the module is to add multiple images. For example, being on the “ Add a new item ” or “ Change an item ” page in the admin, I have tabs on the left side, one of them is “ Item images . When I click, I want the contents of this tab to be my own. Digging into the code, it turned out that Magento uses one of the Varien_Data_Form_Element classes to display this content.for each item in full form. I want to add my own class here, which will display the form elements the way I want. Is this good practice for this, or is there another more elegant way to add your own content to admin forms? EDIT: I have to add that none of the existing classes help my problem.

SOLUTION: I have a controller in my custom module, which is located in Mypackage / Mymodule / controller / Adminhtml / Item.php . In the editAction () method , which I use to add and create new elements, I create 2 blocks: one for the form and one for the tabs:

$ this -> _ addContent ($ this-> getLayout () -> createBlock ('item / adminhtml_edit'))
                    -> _ addLeft ($ this-> getLayout () -> createBlock ('item / adminhtml_edit_tabs'));
$ this-> renderLayout ();

The Block / Adminhtml / Edit / Tabs.php block creates two tabs on the left: General Information and Image Elements , each of them, using the block classes, render different contents on the right.

protected function _beforeToHtml ()
{
   $ this-> addTab ('item_info', array (
        'label' => Mage :: helper ('mymodule') -> __ ('Item Info'),
        'content' => $ this-> getLayout () -> createBlock ('item / adminhtml_edit_tab_form') -> toHtml (),
        ));

   $ this-> addTab ('item_images', array (
        'label' => Mage::helper('mymodule')->__('Item Images'),
        'active' => ( $this->getRequest()->getParam('tab') == 'item_images' ) ? true : false,
        'content' => $this->getLayout()->createBlock('item/adminhtml_images')->toHtml(),
        ));

   return parent::_beforeToHtml();
}

, item_images , varien .

class Mypackage_Mymodule_Block_Adminhtml_Images extends Mage_Core_Block_Template
{
    public function __construct()
    {
        parent::__construct();
        $this->setTemplate('item/images.phtml'); //This is in adminhtml design
    }


    public function getPostId()
    {
    return $this->getRequest()->getParam('id');
    }

    public function getExistingImages()
    {
        return Mage::getModel('mymodule/item')->getImages($this->getPostId());
    }
}

app/design/adminhtml/default/default/template/item/images.phtml :

//You can add your own custom form fields here and all of them will be included in the form
foreach($this->getExistingImages() as $_img):
//Do something with each image
endforeach;
//You can add your own custom form fields here and all of them will be included in the form