pos/pos_payment_change/wizards/view_pos_payment_change_wizard.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
Copyright (C) 2015-Today GRAP (http://www.grap.coop)
@author: Sylvain LE GAL (https://twitter.com/legalsylvain)
License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
-->

<odoo>

    <record id="view_pos_payment_change_wizard_form" model="ir.ui.view">
        <field name="model">pos.payment.change.wizard</field>
        <field name="arch" type="xml">
            <form>
                <group col="4">
                    <field name="order_id" />
                    <field name="amount_total" invisible="1"/>
                    <field name="old_line_ids" colspan="4">
                        <tree>
                            <field name="old_journal_id"/>
                            <field name="amount" sum="Total"/>
                        </tree>
                    </field>
                    <newline />
                    <field name="new_line_ids" colspan="4"
                        context="{'new_line_ids': new_line_ids, 'amount_total': amount_total}">
                        <tree editable="bottom">
                            <field name="new_journal_id" options="{'no_open': True, 'no_create_edit': True}"/>
                            <field name="amount" sum="Total"/>
                        </tree>
                    </field>
                </group>
                <footer>
                    <button name="button_change_payment" string="Change Payments"
                        type="object" class="oe_highlight"/>
                    <button string="Cancel" class="oe_link" special="cancel" />
                </footer>
            </form>
        </field>
    </record>

    <record id="action_pos_payment_change_wizard" model="ir.actions.act_window">
        <field name="name">Change Payments</field>
        <field name="res_model">pos.payment.change.wizard</field>
        <field name="view_type">form</field>
        <field name="view_mode">form</field>
        <field name="target">new</field>
    </record>

</odoo>