How can I get a list of store groups under a website in Magento and then a list of stores from that store group?
Anton's answer, while correct, may be re-inventing the wheel just a bit. There is already a facility in the Magento Core to retrieve this sort of data.
You can retrieve a list of all websites, and their "children" using this:
Mage::getSingleton('adminhtml/system_store')->getStoresStructure()
You can also pass an array of websiteIds, storeIds, or storeGroupIds to the function, to filter the list:
public function getStoresStructure($isAll = false, $storeIds = array(), $groupIds = array(), $websiteIds = array())
Example output:
Array
(
[1] => Array
(
[value] => 1
[label] => Main Website
[children] => Array
(
[1] => Array
(
[value] => 1
[label] => Madison Island
[children] => Array
(
[1] => Array
(
[value] => 1
[label] => English
)
[2] => Array
(
[value] => 2
[label] => French
)
[3] => Array
(
[value] => 3
[label] => German
)
)
)
)
)
)
There is a similar one used to populate the "Store Scope" dropdowns and multi-selects all across the admin section.
Mage::getSingleton('adminhtml/system_store')->getStoreValuesForForm(false, true)
Array
(
[0] => Array
(
[label] => All Store Views
[value] => 0
)
[1] => Array
(
[label] => Main Website
[value] => Array
(
)
)
[2] => Array
(
[label] => Madison Island
[value] => Array
(
[0] => Array
(
[label] => English
[value] => 1
)
[1] => Array
(
[label] => French
[value] => 2
)
[2] => Array
(
[label] => German
[value] => 3
)
)
)
)
To discover this, I located a multi-select on the Admin that has the data I wanted, then I turned on template hints to find out which block class was responsible for rendering it: Mage_Adminhtml_Block_Cms_Page_Edit_Form
. Knowing this, I found the class in the codebase,(app/code/core/Mage/Adminhtml/Block/Cms/Block/Edit/Form.php) and located the part that creates the input by searching for its label ("Store View"). This showed me how the input's values were being provided:
$field =$fieldset->addField('store_id', 'multiselect', array(
'name' => 'stores[]',
'label' => Mage::helper('cms')->__('Store View'),
'title' => Mage::helper('cms')->__('Store View'),
'required' => true,
'values' => Mage::getSingleton('adminhtml/system_store')->getStoreValuesForForm(false, true),
));
The Mage::getSingleton('adminhtml/system_store')
points to the class Mage_Adminhtml_Model_System_Store
, where I found a variety of similar methods that can also be useful. Have a look for yourself.