获取已删除类别的ID [Magento]

Question

如何从观察者中获取已删除类别的ID？

config.xml标记

<adminhtml>
    <events>
        <catalog_category_delete_after>
            <observers>
                <my_module>
                    <type>singleton</type>
                    <class>my_module/observer</class>
                    <method>onCategoryDeleteAfter</method>
                </my_module>
            </observers>
        </catalog_category_delete_after>
    </events>
</adminhtml>

观察者代码类似于：

class My_Module_Model_Observer
{
    public function onCategoryDeleteAfter() {    
        #do something with deleted category id
    }
}

Answer 1

使用传递的$ observer变量。

class My_Module_Model_Observer
{
    public function onCategoryDeleteAfter($observer) {
        $observer->getEvent()->getCategory();
    }
}