flectra/addons/product/views/product_attribute_views.xml

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

    <record id="product_attribute_value_view_tree" model="ir.ui.view">
        <field name="name">product.attribute.value.view.tree</field>
        <field name="model">product.attribute.value</field>
        <field name="arch" type="xml">
            <tree string="Attributes" editable="top">
                <field name="sequence" widget="handle"/>
                <field name="attribute_id"/>
                <field name="name"/>
                <field name="price_extra"/>
            </tree>
        </field>
    </record>
    <record id="product_attribute_value_action" model="ir.actions.act_window">
        <field name="name">Variant Values</field>
        <field name="type">ir.actions.act_window</field>
        <field name="res_model">product.attribute.value</field>
        <field name="view_mode">tree</field>
        <field name="view_type">form</field>
        <field name="view_id" ref="product_attribute_value_view_tree"/>
        <field name="domain">[('product_ids.product_tmpl_id', '=', active_id)]</field>
        <field name="context">{'default_product_tmpl_id': active_id}</field>
    </record>

        <record id="attribute_tree_view" model="ir.ui.view">
            <field name="name">product.attribute.tree</field>
            <field name="model">product.attribute</field>
            <field name="arch" type="xml">
                <tree string="Variant Values" editable="top">
                    <field name="sequence" widget="handle"/>
                    <field name="name"/>
                    <field name="create_variant" groups="base.group_no_one"/>
                </tree>
            </field>
        </record>

        <record id="product_attribute_view_form" model="ir.ui.view">
            <field name="name">product.attribute.form</field>
            <field name="model">product.attribute</field>
            <field name="arch" type="xml">
                <form string="Product Attribute">
                    <group>
                        <group name="main_fields">
                            <label for="name" string="Attribute Name"/>
                            <field name="name" nolabel="1"/>
                        </group>
                    </group>
                    <group name="values_ids">
                        <label for="value_ids" string="Attribute Values"/>
                        <field name="value_ids" widget="one2many_list" nolabel="1">
                            <tree string="Values" editable="bottom">
                                <field name="name"/>
                            </tree>
                            <form string="Values">
                                <field name="name"/>
                            </form>
                        </field>
                        <field name="create_variant" groups="base.group_no_one"/>
                    </group>
                </form>
            </field>
        </record>

        <record id="attribute_action" model="ir.actions.act_window">
            <field name="name">Attributes</field>
            <field name="type">ir.actions.act_window</field>
            <field name="res_model">product.attribute</field>
            <field name="view_mode">tree</field>
            <field name="view_type">form</field>
        </record>

        <record id="variants_tree_view" model="ir.ui.view">
            <field name="name">product.attribute.value.tree</field>
            <field name="model">product.attribute.value</field>
            <field name="arch" type="xml">
                <tree string="Variant Values" editable="top">
                    <field name="sequence" widget="handle"/>
                    <field name="attribute_id"/>
                    <field name="name"/>
                </tree>
            </field>
        </record>

        <record id="variants_action" model="ir.actions.act_window">
            <field name="name">Attribute Values</field>
            <field name="type">ir.actions.act_window</field>
            <field name="res_model">product.attribute.value</field>
            <field name="view_mode">tree</field>
            <field name="view_type">form</field>
        </record>

    <record id="product_attribute_line_form" model="ir.ui.view">
        <field name="name">product.attribute.line.form</field>
        <field name="model">product.attribute.line</field>
        <field name="mode">primary</field>
        <field name="priority" eval="8"/>
        <field name="arch" type="xml">
            <form string="Product Attribute and Values">
                <group name="main_field">
                    <label for="attribute_id" string="Attribute Name"/>
                    <field name="attribute_id" nolabel="1"/>
                    <field name="value_ids" widget="one2many_list">
                        <tree string="Values">
                            <field name="name"/>
                        </tree>
                        <form string="Values">
                            <field name="name"/>
                        </form>
                    </field>
                </group>
            </form>
        </field>
    </record>

</flectra>