Custom module controller 404 error

Question

My controller is not being read by Magento though and I can't find my error. I would like it to extend the admin sales order info controller and pass a variable to the renderLayout().

config.xml:

<config>
    <-- other -->
    <admin>
        <routers>
            <adminhtml>
                <args>
                    <modules>
                        <mymodule before="Mage_Adminhtml">MyApp_MyModule_Adminhtml</mymodule>
                    </modules>
                </args>
            </adminhtml>
        </routers>
    </admin>
    <!--other-->
</config>

MyApp\MyModule\controllers\IndexController.php:

class MyApp_MyModule_Adminhtml_IndexController extends Mage_Adminhtml_Controller_Action {
    public function indexAction()
    {
        $this->loadLayout();
        Mage::helper("adminhtml")->getUrl("myapp_mymodule/index/index");
        $this->renderLayout();
    }
}

Answer 1

You can either move you controller file location or update you config.xml

Method 1 : Move your controller file from

MyApp\MyModule\controllers\ButtonController.php

to

MyApp\MyModule\controllers\Adminhtml\ButtonController.php

Or Method 2 : change your config.xml and update your class definition

<mymodule before="Mage_Adminhtml">MyApp_MyModule_Adminhtml</mymodule>

to

 <mymodule before="Mage_Adminhtml">MyApp_MyModule</mymodule>