delivery_asm_view.xml

<?xml version="1.0" encoding="utf-8" ?>
<!-- Copyright 2020 Tecnativa - David Vidal
     License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl). -->
<odoo>
    <record id="view_delivery_carrier_form" model="ir.ui.view">
        <field name="model">delivery.carrier</field>
        <field name="inherit_id" ref="delivery.view_delivery_carrier_form" />
        <field name="arch" type="xml">
            <xpath expr="//notebook/page[1]" position='before'>
                <page
                    string="GLS Configuration"
                    attrs="{'invisible': [('delivery_type', '!=', 'gls_asm')]}"
                >
                    <group>
                        <group>
                            <field
                                name="gls_asm_uid"
                                attrs="{'required': [('delivery_type', '=', 'gls_asm'), ('prod_environment', '!=', False)]}"
                            />
                            <field
                                name="gls_asm_service"
                                attrs="{'required': [('delivery_type', '=', 'gls_asm'), ('prod_environment', '!=', False)]}"
                            />
                            <field
                                name="gls_asm_shiptime"
                                attrs="{'required': [('delivery_type', '=', 'gls_asm'), ('prod_environment', '!=', False)]}"
                            />
                            <field
                                name="gls_asm_postage_type"
                                attrs="{'required': [('delivery_type', '=', 'gls_asm'), ('prod_environment', '!=', False)]}"
                            />
                            <field name="gls_asm_cash_on_delivery" />
                        </group>
                    </group>
                </page>
            </xpath>
            <xpath expr="//button[@name='toggle_prod_environment']" position="before">
                <button
                    name="action_get_manifest"
                    string="Manifest"
                    type="object"
                    class="oe_stat_button"
                    icon="fa-file-text-o"
                    attrs="{'invisible': [('delivery_type', '!=', 'gls_asm')]}"
                />
            </xpath>
        </field>
    </record>
</odoo>