In class “Mage_Core_Controller_Varien_Front” we have the “loadLayout()” function. This in turn calls the “addActionLayoutHandles()” function, which adds the required handles for each controller/action.
How can layout XML files be registered for the frontend and adminhtml areas?
These are defined in config.xml of each module in ‘fontend/layout/updates’
How can code be modified or added to Magento pages using the following methods?
− Template customizations
I guess we can add any kind of code we require in phtml files. We can access models, collections, controllers, etc, etc
− Layout customizations
We can add new blocks, remove blocks, replace template files of existing blocks
− Overriding block classes
Again by overriding blocks we can extend its features and change how the block works.
− Registering observers on general block events
We can intercept block html, make changes to scope variable inside the block