Hi,

To add a menu item under a menu is an easy task what you have to do is define and the new menu and add parent attribute, and give parent="mrp_menu_id" so that your new menu will be created under the MRP.

Along with the menu you have to define the action of the menu, ie what has to be take place upon clicking the menu, if it is not given the menu will not be visible .

<menuitem id="id_for_new_menu" parent="id_of_parent" name="String to display in menu"
          action="action_on_clicking_menu/>

This is how you can define a new menu, other than this you can use attributes such as groups and sequence along with the above.

To get the parent id of a menu item, what you can do is activate developer mode and go to Settings -> Technical -> User Interface -> Menu Items -> Search the menu, open it , click on lady debugger button(button near logged in user name) and click on View Meta data, in the opening wizard, you can see the id of the menu, ie XML ID

...

Thanks

Thanks for your answers, I've kinda advanced my code and I get the following error (Model not found):

File "/opt/odoo/odoo-server/odoo/models.py", line 1083, in _validate_fields
    raise ValidationError("%s\n\n%s" % (_("Error while validating constraint"), tools.ustr(e)))
ParseError: "Error mientras se validavan las restricciones

Modelo no encontrado: menu.mrp.test.wizard

Error de contexto:
Vista `Menu MRP`
[view_id: 3532, xml_id: n/a, model: menu.mrp.test.wizard, parent_id: n/a]
None" while parsing /opt/odoo/custom/migsamx/mrp_menu/wizard/mrp_menu_wizard_view.xml:4, near
<record id="oee_report_wizard" model="ir.ui.view">
        <field name="name">Menu MRP</field>
        <field name="model">menu.mrp.test.wizard</field>
        <field name="arch" type="xml">
            <form>
                <group name="date_range">
                    <field name="date_range_id"/>
                </group>
                <group name="date_fields">
                    <field name="date_from"/>
                    <field name="date_to"/>
                </group>
            </form>
        </field>
    </record>

models folder:

__init__.py

# -*- coding: utf-8 -*-

from . import mrp

mrp.py

# -*- coding: utf-8 -*-

from odoo import models


class MrpMenu(models.Model):
    _inherit = 'mrp.workcenter'

views folder:

mrp_view.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>
    <record model="ir.ui.view" id="view_mrp_specific_form">
        <field name="name">mrp.workcenter.form.inherit</field>
        <field name="inherit_id" ref="mrp.mrp_workcenter_view"/>
        <field name="model">mrp.workcenter</field>
        <field name="type">form</field>
    </record>
</odoo>

wizard folder:

__init__.py

# -*- coding: utf-8 -*-

from . import mrp_menu_wizard

mrp_menu_wizard.py

# -*- coding: utf-8 -*-

from odoo import models, fields, api


class MenuWizardTest(models.TransientModel):

    _name = "menu.mrp.test.wizard"
    _description = "OEE Reports"

    date_from = fields.Date(Required=True)
    date_to = fields.Date(Required=True)

    date_range_id = fields.Many2one(
        comodel_name='date.range',
        string='Date range'
    )

    @api.onchange('date_range_id')
    def onchange_date_range_id(self):
        self.date_from = self.date_range_id.date_start
        self.date_to = self.date_range_id.date_end

mrp_menu_wizard_view.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>

    <record id="oee_report_wizard" model="ir.ui.view">
        <field name="name">Menu MRP</field>
        <field name="model">menu.mrp.test.wizard</field>
        <field name="arch" type="xml">
            <form>
                <group name="date_range">
                    <field name="date_range_id"/>
                </group>
                <group name="date_fields">
                    <field name="date_from"/>
                    <field name="date_to"/>
                </group>
            </form>
        </field>
    </record>

    <act_window id="action_menu_test_wizard"
                name="OEE Reports"
                res_model="menu.mrp.test.wizard"
                view_type="form"
                view_mode="form"
                view_id="oee_report_wizard"
                target="new" />

</odoo>

mrp_menu (main module folder):

__init__.py

# -*- coding: utf-8 -*-
#Made by Daniel Medina

from . import models
from . import wizard

__manifest__.py

<?xml version="1.0" encoding="utf-8"?>
<odoo>

   <menuitem
      parent="mrp.menu_mrp_reporting"
      id="menu_oee_reports"
      name="OEE Reports"
      groups="mrp.group_mrp_manager"
      />

    <menuitem
       parent="menu_oee_reports"
       action="action_menu_test"
       id="menu_oee_wizard"
       sequence="10"
       />

</odoo>

mrp_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>

   <menuitem
      parent="mrp.menu_mrp_reporting"
      id="menu_oee_reports"
      name="OEE Reports"
      groups="mrp.group_mrp_manager"
      />

    <menuitem
       parent="menu_oee_reports"
       action="action_menu_test"
       id="menu_oee_wizard"
       sequence="10"
       />

</odoo>