flectra/addons/event_sale/views/event_views.xml

<?xml version="1.0" encoding="utf-8"?>
<flectra>
        <record id="view_event_registration_ticket_search" model="ir.ui.view">
            <field name="name">event.registration.search.inherit</field>
            <field name="model">event.registration</field>
            <field name="inherit_id" ref="event.view_registration_search" />
            <field name="arch" type="xml">
                <filter name="group_event" position="after">
                    <filter string="Ticket Type" domain="[]" context="{'group_by':'event_ticket_id'}"/>
                </filter>
            </field>
        </record>

        <record id="view_event_registration_ticket_tree" model="ir.ui.view">
            <field name="name">event.registration.tree.inherit</field>
            <field name="model">event.registration</field>
            <field name="inherit_id" ref="event.view_event_registration_tree" />
            <field name="arch" type="xml">
                <field name="event_id" position="after">
                    <field name="event_ticket_id"/>
                    <field name="origin"/>
                </field>
            </field>
        </record>

        <record id="view_event_registration_ticket_form" model="ir.ui.view">
            <field name="name">event.registration.form.inherit</field>
            <field name="model">event.registration</field>
            <field name="inherit_id" ref="event.view_event_registration_form" />
            <field name="arch" type="xml">
                <field name="event_id" position="after">
                    <field name="event_ticket_id" domain="[('event_id', '=', event_id)]"/>
                </field>
                <group name="event" position="after">
                    <group string="Origin">
                        <field name="sale_order_id"/>
                        <field name="origin" attrs="{'invisible': [('sale_order_id', '!=', False)]}"/>
                        <field name="sale_order_line_id" readonly="1" attrs="{'invisible': [('sale_order_id', '=', False)]}"/>
                    </group>
                </group>
            </field>
        </record>

        <record id="event_type_view_form_inherit_sale" model="ir.ui.view">
            <field name="name">event.type.view.form.inherit.sale</field>
            <field name="model">event.type</field>
            <field name="inherit_id" ref="event.view_event_type_form"/>
            <field name="arch" type="xml">
                <div name="event_type_attendees_auto_confirm" position="after">
                    <div class="col-xs-12 col-md-12 o_setting_box">
                        <div class="o_setting_left_pane">
                            <field name="use_ticketing"/>
                        </div>
                        <div class="o_setting_right_pane">
                            <label for="use_ticketing"/>
                            <div class="row mt16" attrs="{'invisible': [('use_ticketing', '=', False)]}">
                                <div class="col-md-9">
                                    <field name="event_ticket_ids">
                                        <tree string="Tickets" editable="bottom">
                                            <field name="name"/>
                                            <field name="product_id"/>
                                            <field name="price"/>
                                        </tree>
                                    </field>
                                </div>
                            </div>
                        </div>
                    </div>
                </div>
            </field>
        </record>

        <record id="view_event_form_inherit_ticket" model="ir.ui.view">
            <field name="name">event.form.inherit</field>
            <field name="model">event.event</field>
            <field name="inherit_id" ref="event.view_event_form"/>
            <field name="arch" type="xml">
                <page name="event_mail_schedule" position="before">
                    <page string="Tickets">
                        <field name="event_ticket_ids" context="{'default_name': name}">
                            <tree string="Tickets" editable="bottom">
                                <field name="name"/>
                                <field name="product_id" context="{'default_event_ok':1}"/>
                                <field name="deadline"/>
                                <field name="price"/>
                                <field name="seats_max"/>
                                <field name="seats_reserved" readonly="1"/>
                                <field name="seats_unconfirmed" readonly="1"/>
                            </tree>
                        </field>
                    </page>
                </page>
            </field>
        </record>

        <record id="event_ticket_form_view" model="ir.ui.view">
            <field name="name">event.event.ticket.form</field>
            <field name="model">event.event.ticket</field>
            <field name="arch" type="xml">
                <form string="Event's Ticket">
                    <div class="oe_title">
                        <label for="name" class="oe_edit_only"/>
                        <h1><field name="name" placeholder="Event Name"/></h1>
                    </div>
                    <group>
                        <group>
                            <field name="event_id"/>
                            <field name="seats_availability"/>
                            <field name="seats_available"/>
                            <field name="deadline"/>
                            <field name="price"/>
                            <field name="price_reduce" groups="base.group_no_one"/>
                        </group>
                        <group>
                            <field name="seats_max"/>
                            <field name="seats_reserved"/>
                            <field name="seats_unconfirmed"/>
                            <field name="seats_used"/>
                            <field name="product_id"/>
                            <field name="is_expired"/>
                        </group>
                    </group>
                </form>
            </field>
        </record>

</flectra>