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Magento Fundamentals for Developers
Configuration options in Magento can store values on three scopes (global, website,
and store view); by default, all the values are set on the global scope. By using
system.xml on our modules, we can specify the scopes on which the configuration
options can be set; let's revisit our previous system.xml:
…
Enabled
HTML]]>
select
adminhtml/system_config_source_yesno
10
1
1
1
…
Factory names and functions
Magento makes use of factory methods to instantiate Model, Helper, and Block
classes. A factory method is a design pattern that allows us to instantiate an object
without using the exact class name and using a class alias instead.
Magento implements several factory methods, as follows:
• Mage::getModel()
• Mage::getResourceModel()
• Mage::helper()
• Mage::getSingleton()
• Mage::getResourceSingleton()
• Mage::getResourceHelper()
Each of these methods takes a class alias that is used to determine the real class name
of the object that we are trying to instantiate; for example, if we wanted to instantiate
a product object, we can do so by calling the getModel() method:
$product = Mage::getModel('catalog/product');
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