social/mass_mailing_custom_unsubscribe/views/mail_unsubscription_view.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright 2016 Jairo Llopis <jairo.llopis@tecnativa.com>
     License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl). -->

<odoo>

<record id="mail_unsubscription_view_form" model="ir.ui.view">
    <field name="name">Mail Unsubscription Form</field>
    <field name="model">mail.unsubscription</field>
    <field name="arch" type="xml">
        <form>
            <sheet>
                <group>
                    <field name="date"/>
                    <field name="mass_mailing_id"/>
                    <field name="unsubscriber_id"/>
                    <field name="mailing_list_id"/>
                    <field name="email"/>
                    <field name="action"/>
                    <field name="reason_id"
                           attrs="{'required': [('action', '=', 'unsubscription')]}"/>
                    <field name="details"
                           attrs="{'required': [('details_required', '=', True)]}"/>
                    <field name="details_required" invisible="True"/>
                    <field name="metadata"/>
                </group>
            </sheet>
            <div class="oe_chatter">
                <field name="message_follower_ids"
                       widget="mail_followers"
                       groups="base.group_user"/>
                <field name="message_ids"
                       widget="mail_thread"/>
           </div>
        </form>
    </field>
</record>

<record id="mail_unsubscription_view_tree" model="ir.ui.view">
    <field name="name">Mail Unsubscription Tree</field>
    <field name="model">mail.unsubscription</field>
    <field name="arch" type="xml">
        <tree decoration-warning="action == 'unsubscription'">
            <field name="date"/>
            <field name="mass_mailing_id"/>
            <field name="unsubscriber_id"/>
            <field name="mailing_list_id"/>
            <field name="email" invisible="True"/>
            <field name="action"/>
            <field name="reason_id"/>
            <field name="details" invisible="True"/>
        </tree>
    </field>
</record>

<record id="mail_unsubscription_view_search" model="ir.ui.view">
    <field name="name">Mail Unsubscription Search</field>
    <field name="model">mail.unsubscription</field>
    <field name="arch" type="xml">
        <search>
            <field name="mass_mailing_id"/>
            <field name="unsubscriber_id"/>
            <field name="mailing_list_id"/>
            <field name="email"/>
            <field name="reason_id"/>
            <field name="details"/>
            <separator/>
            <group string="Group by">
                <filter string="Month"
                        context="{'group_by': 'date:month'}"/>
                <filter string="Year"
                        context="{'group_by': 'date:year'}"/>
                <filter string="Action"
                        context="{'group_by': 'action'}"/>
                <filter string="Email"
                        context="{'group_by': 'email'}"/>
                <filter string="Reason"
                        context="{'group_by': 'reason_id'}"/>
                <filter string="Mass mailing"
                        context="{'group_by': 'mass_mailing_id'}"/>
            </group>
        </search>
    </field>
</record>

<record model="ir.ui.view" id="mail_unsubscription_view_pivot">
    <field name="name">Mail Unsubscription Pivot</field>
    <field name="model">mail.unsubscription</field>
    <field name="arch" type="xml">
        <pivot string="(Un)subscriptions">
            <field name="reason_id" type="row"/>
            <field name="mailing_list_id" type="row"/>
            <field name="action" type="col"/>
        </pivot>
    </field>
</record>

<record model="ir.ui.view" id="mail_unsubscription_view_graph">
    <field name="name">Mail Unsubscription Graph</field>
    <field name="model">mail.unsubscription</field>
    <field name="arch" type="xml">
        <graph string="(Un)subscriptions">
            <field name="date" type="row"/>
            <field name="action" type="col"/>
        </graph>
    </field>
</record>

<act_window id="mail_unsubscription_action"
            name="(Un)subscriptions"
            view_mode="tree,form,pivot,graph"
            res_model="mail.unsubscription"/>

<menuitem id="mail_unsubscription_menu"
          parent="mass_mailing.mass_mailing_menu"
          action="mail_unsubscription_action"/>

</odoo>