How to make custom menu in magento admin panel and make it work?

Question

I create a menu Employee on admin panel. This menu has a sub menu Manage Employees. When I click on Manage Employees I get an 404 error. The given below are my codes:

The given below is a part of my controller Location: /var/www/html/magento/app/code/local/Test/User/etc

<adminhtml>
  <menu>
   <user module="adminhtml">
    <title>Employee</title>
    <sort_order>71</sort_order>              
    <children>
     <items module="user">
      <title>Manage Employees</title>
      <sort_order>0</sort_order>
      <action>adminhtml/adminhtml_employee/</action>
     </items>
    </children>
   </user>
  </menu>
  <acl>
   <resources>
    <all>
     <title>Allow Everything</title>
    </all>
    <admin>
     <children>
      <Test_User>
       <title>Employee Module</title>
       <sort_order>10</sort_order>
      </Test_User>
     </children>
    </admin>
   </resources>
  </acl>
  <layout>
   <updates>
    <user>
     <file>user.xml</file>
    </user>
   </updates>
  </layout>
 </adminhtml> 

This is my controller Location: /var/www/html/magento/app/code/local/Test/User/controllers/Adminhtml

<?php
 class Test_User_Adminhtml_EmployeeController extends Mage_Adminhtml_Controller_action
  {
   public function indexAction()
    {
     $this->loadLayout();
     $this->renderLayout();
    }
  }
?>

This are the block files Location: /var/www/html/magento/app/code/local/Test/User/Block/Adminhtml

<?php
 class Test_User_Block_Adminhtml_Employee extends Mage_Adminhtml_Block_Widget_Grid_Container
  {
   public function __construct()
   {
    $this->_controller = 'adminhtml_employee';
    $this->_blockGroup = 'employee';
    $this->_headerText = Mage::helper('employee')->__('Employee Manager');
    $this->_addButtonLabel = Mage::helper('employee')->__('Add Employee');
    parent::__construct();
   }
  }
?>

Location: /var/www/html/magento/app/code/local/Test/User/Block/Adminhtml/Employee

<?php 
 class Test_User_Block_Adminhtml_Employee_Grid extends Mage_Adminhtml_Block_Widget_Grid
  {
    public function __construct()
    {
        parent::__construct();
        $this->setId('employeeGrid');
        $this->setDefaultSort('id');
        $this->setDefaultDir('ASC');
        $this->setSaveParametersInSession(true);
    }

    protected function _prepareCollection()
    {
        $collection = Mage::getModel('user/employee')->getCollection();
        $this->setCollection($collection);
        return parent::_prepareCollection();
    }

    protected function _prepareColumns()
    {
        $this->addColumn('id', array(
          'header'    => Mage::helper('employee')->__('ID'),
          'align'     =>'right',
          'width'     => '10px',
          'index'     => 'id',
        ));

        $this->addColumn('name', array(
          'header'    => Mage::helper('employee')->__('Name'),
          'align'     =>'left',
          'index'     => 'name',
          'width'     => '50px',
        ));


        $this->addColumn('content', array(
            'header'    => Mage::helper('employee')->__('Description'),
            'width'     => '150px',
            'index'     => 'content',
        ));
        return parent::_prepareColumns();
    }
  }
?>

and this is my xml file user.xml present inside my module:

<?xml version="1.0"?>
<layout version="0.1.0">
<employee_adminhtml_employee_index>
        <reference name="content">
            <block type="employee/adminhtml_employee" name="employee" />
        </reference>
    </employee_adminhtml_employee_index>
</layout>

Answer 1

add this in you config.xml

   <admin>
        <routers>
             <adminhtml>
                <args>
                    <modules>
                        <Test_User before="Mage_Adminhtml">Test_User_Adminhtml</Test_User>
                    </modules>
                </args>
            </adminhtml>
        </routers>
    </admin>

then in you layout xml mean user.xml

<?xml version="1.0"?>
<layout version="0.1.0">
<adminhtml_employee_index>
        <reference name="content">
            <block type="employee/adminhtml_employee" name="employee" />
        </reference>
    </adminhtml_employee_index>
</layout>

Now the action will be

<adminhtml>
  <menu>
   <user module="adminhtml">
    <title>Employee</title>
    <sort_order>71</sort_order>              
    <children>
     <items module="user">
      <title>Manage Employees</title>
      <sort_order>0</sort_order>
      <action>adminhtml/employee/</action>
     </items>
    </children>
   </user>
  </menu>
  <acl>
   <resources>
    <all>
     <title>Allow Everything</title>
    </all>
    <admin>
     <children>
      <Test_User>
       <title>Employee Module</title>
       <sort_order>10</sort_order>
      </Test_User>
     </children>
    </admin>
   </resources>
  </acl>
  <layout>
   <updates>
    <user>
     <file>user.xml</file>
    </user>
   </updates>
  </layout>
 </adminhtml>