Magento - Add field to actions in Catalog Price Rules - magento

Question

I want to add a custom field to the actions tab in the Catalog Price Rules section.
This is what I did:
I added these lines to the file app\code\core\Mage\Adminhtml\Block\Promo\Catalog\Edit\Tab\Actions.php
$fieldset->addField('custom_field', 'select', array(
'label' => 'Custom Field',
'title' => 'Custom Field',
'name' => 'custom_field',
'options' => array(
'1' => Mage::helper('catalogrule')->__('Yes'),
'0' => Mage::helper('catalogrule')->__('No'),
),
));
I changed the version to 1.6.0.4 in this file: app\code\core\Mage\CatalogRule\etc\config.xml
<Mage_CatalogRule>
<version>1.6.0.4</version>
</Mage_CatalogRule>
I created new file with the name app\code\core\Mage\CatalogRule\sql\catalogrule_setup\upgrade-1.6.0.3-1.6.0.4.php
$installer->startSetup();
$ruleProductTable = $installer->getTable('catalogrule/rule');
$columnOptions = array(
'TYPE' => Varien_Db_Ddl_Table::TYPE_SMALLINT,
'UNSIGNED' => true,
'NULLABLE' => false,
'DEFAULT' => 0,
'COMMENT' => 'Custom Field',
);
$installer->getConnection()->addColumn($ruleProductTable, 'custom_field', $columnOptions);
$installer->endSetup();
Then, I logged in to the admin panel and tried to edit one of the catalog price rules.
I saw my new field in the actions tab - great!
But when I click "Save", the changes that I made in that field, was not saved.
I logged in to the phpmyadmin and went to catalogrule table.
In this table I can see the new field custom_field, with the value 0 (default) - so It really didn't save the changed.
My question is what I did wrong?
Why the changed in the custom_field didn't saved in the DB?
Thanks

Answer 1

I'm not sure why it isn't working for you my guess is your installer isn't being called. I managed the modification through a module and local edits to future proof the change.
Directory structure:
/app/code/local/custom/promo
/app/code/local/custom/promo/etc/
/app/code/local/custom/promo/sql
/app/code/local/custom/promo/sql/promo_setup
/app/code/core/local/Adminhtml/Block/Promo/Catalog/Edit/Tab
add file /app/code/local/custom/promo/etc/config.xml
<?xml version="1.0"?>
<config>
<modules>
<Custom_Promo>
<version>1.0</version>
</Custom_Promo>
</modules>
<global>
<resources>
<promo_setup>
<setup>
<module>Custom_Promo</module>
<class>Mage_Catalog_Model_Resource_Setup</class>
</setup>
</promo_setup>
</resources>
</global>
</config>
add file /app/code/local/custom/promo/sql/promo_setup/install-1-0.php
/* #var $installer Mage_Core_Model_Resource_Setup */
$installer = $this;
$installer->startSetup();
$ruleProductTable = $installer->getTable('catalogrule/rule');
$columnOptions = array(
'TYPE' => Varien_Db_Ddl_Table::TYPE_BOOLEAN,
'NULLABLE' => false,
'COMMENT' => 'Custom Promo',
);
$installer->getConnection()->addColumn($ruleProductTable, 'custom_promo', $columnOptions);
$installer->endSetup();
Clear caches and verify the column is added by looking at the catalog_rule table
SELECT * FROM catalogrule;
Finally take a copy of /app/code/core/Mage/Adminhtml/Block/Promo/Catalog/Edit/Tab/Main.php and create the same file /app/code/core/local/Adminhtml/Block/Promo/Catalog/Edit/Tab/Main.php
Edit the file and add the field before $form->setValues($model->getData());
//Custom Promo
$fieldset->addField('custom_promo', 'select', array(
'label' => 'Custom Promo',
'title' => 'Custom Promo',
'name' => 'custom_promo',
'options' => array(
'1' => Mage::helper('catalogrule')->__('Yes'),
'0' => Mage::helper('catalogrule')->__('No'),
),
));