How to add section to admin tag edit form

Question

I'm writing my custom module, and i'me searching the possibility to add a custom grid to admin tag edit form to handle my_entity-to-tag relation. Anyone knows how to implement that?

Answer 1

Assigning tabs magento do in _prepareLayout method.

You can see an example here:

Mage_Adminhtml_Block_Tag_Edit_Assigned

To add your own tab you need to use, for example event core_block_abstract_prepare_layout_after

add following to your module etc/config.xml :

<adminhtml>
    <events>
        <core_block_abstract_prepare_layout_after>
            <observers>
                <add_new_tab>
                    <type>singleton</type>
                    <class>company_module/observer</class>
                    <method>addTabToTag</method>
                </add_new_tab>
            </observers>
        </core_block_abstract_prepare_layout_after>
    </events>
</adminhtml>

Don't forget include in your event check like this:

$yourBlock instanceof Mage_Adminhtml_Block_Tag_Edit_Assigned

At all code of your observer will be like this:

public function addTabToTag($observer)
{
    $block = $observer->getBlock();
    if($block instanceof Mage_Adminhtml_Block_Tag_Edit_Assigned)
    {
        $tagModel = Mage::registry('current_tag');

        $block->addItem('custom_tab', array(
            'title'         => Mage::helper('tag')->__('Custom Tag'),
            'ajax'          => true,
            'content_url'   => $block->getUrl('*/*/assigned', array('ret' => 'all', 'tag_id'=>$tagModel->getId(), 'store'=>$tagModel->getStoreId())),
        ));
    }
}

As you can see you have here $this->getUrl('*/*/assigned'

You need to replace it with some another controller action.

To be continued ....

As far as I can see this controller/action has only load and render layout. You need to rewrite this controller (if you need help - just tell) and add following method:

public function customAction()
{
    $this->_initTag();
    $this->loadLayout();
    $this->renderLayout();
}

Then you need to add content to this block. It makes by layout. Open /app/design/adminhtml/default/default/layout/tag.xml and you can see examples there:

<adminhtml_tag_product>
    <block type="core/text_list" name="root" output="toHtml">
        <block type="adminhtml/tag_product_grid" name="adminhtml.tag.product.grid"/>
    </block>
</adminhtml_tag_product>

<adminhtml_tag_customer>
    <block type="core/text_list" name="root" output="toHtml">
        <block type="adminhtml/tag_customer_grid" name="adminhtml.tag.customer.grid"/>
    </block>
</adminhtml_tag_customer>

In block class Mage_Adminhtml_Block_Tag_Customer_Grid you can see an example how to create your own grid.

If you have any question - just ask.