golem/golem_member_minor/wizard/golem_membership_invoice.xml

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

<!--
Copyright 2018 Fabien Bourgeois <fabien@yaltik.com>
Copyright 2018 Youssef El Ouahby <youssef@yaltik.com>

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Affero General Public License for more details.

You should have received a copy of the GNU Affero General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
-->

<odoo>
  <data>

    <!-- Forms -->
    <record id="golem_membership_invoice_form_inherit" model="ir.ui.view">
      <field name="name">membership.invoice.view.form_iherit</field>
      <field name="model">golem.membership.invoice</field>
      <field name="inherit_id" ref="golem_membership.golem_membership_invoice_form" />
      <field name="arch" type="xml">
        <field name='product_id' position='before'>
            <field name='src_member_id' invisible="1" />
            <field name='src_member_minor' invisible="1" />
            <field name='partner_id' string="Legal guardian"
              options="{'no_create': True}"
              attrs="{'invisible': [('src_member_id', '=', False)], 'required': [('src_member_minor', '=', True)]}" />
        </field>
      </field>
    </record>

  </data>
</odoo>