how to define custom layout for different controller parameters passed

Question

I have a controller and want to define or render custom layout for different parameters passed from user to it:

    public function myactionAction() {

            $this->loadLayout();

            $params = $this->getRequest()->getParams();

            if(array_key_exists('customaction', $params)){
                     // default layout
                    ...
            }
            elseif(array_key_exists('another_subaction', $params))
            {
                   // different layout
                    ...
            }

i tried some xml in layouts:

<mymodulerouter_mycontroller_myaction_customaction>
        <reference name="root">
        <action method="setTemplate"><template>customer/custom.phtml</template></action>
    </reference>
</mymodulerouter_mycontroller_myaction_customaction>

but no success, is it possible to to this is magento or i should register another controller?

Answer 1

Yes this is possible with Magento and you don't need a new controller.

I would consider creating an observer however that observes the controller_action_layout_load_before event.

<events>
        <controller_action_layout_load_before>
            <observers>
                <mymodule_controller_action_layout_load_before>
                    <class>mymodule/observer</class>
                    <method>loadSomeLayout</method>
                </mymodule_controller_action_layout_load_before>
            </observers>
        </controller_action_layout_load_before>
    </events>

Inside your observer method you could get the request and test the parameters before adding a handle to the layout update.

class Namespace_Mymodule_Model_Observer
{
    public function loadSomeLayout($observer) {
        $layout = $observer->getEvent()->getLayout();
        $param = Mage::app()->getRequest()->getParam('hello');
        if ($param == "world")
            $layout->getUpdate()->addHandle('hello_world_default');
    }
}

Then, in your layout xml:

<hello_world_default>
        <reference name="root">
        <action method="setTemplate"><template>customer/custom.phtml</template></action>
    </reference>
</hello_world_default>