odoo 10: extending form view tree of related records (inventory.stock.line) - forms

Question

I need to extend a form (stock.view_inventory_form) in Odoo 10. The form has a sub-tree populated with related records from another model. Here's the part of the original form that I want to change:
<field name="line_ids" string="Inventory Details" context="{'default_location_id': location_id, 'default_product_id': product_id, 'default_prod_lot_id': lot_id, 'default_package_id': package_id, 'default_partner_id': partner_id}" mode="tree,kanban">
<tree string="Inventory Details" editable="bottom" decoration-info="product_qty != theoretical_qty" decoration-danger="theoretical_qty < 0">
<field name="product_id" domain="[('type','=','product')]"/>
<field name="product_uom_id" string="UoM" groups="product.group_uom"/>
<field name="location_id" domain="[('id', 'child_of', parent.location_id)]" groups="stock.group_stock_multi_locations"/>
<field name="prod_lot_id" domain="[('product_id', '=', product_id)]" context="{'default_product_id': product_id}" groups="stock.group_production_lot"/>
<field name="package_id" domain="['|', ('location_id','=', False), ('location_id', '=', location_id)]" groups="stock.group_tracking_lot"/>
<field name="partner_id" groups="stock.group_tracking_owner"/>
<field name="theoretical_qty" readonly="1"/>
<field name="product_qty" string="Real Quantity"/>
<field name="state" invisible="True"/>
</tree>
</field>
Where line_ids is a field from a related model (stock.inventory.line). So I extended the model with the following:
class stock_inventory_line(models.Model):
_inherit = 'stock.inventory.line'
x_container_details = fields.Char('Container details')
x_wagon_no = fields.Char('Wagon No')
x_seal_no = fields.Char('Seal No')
x_invoice_no = fields.Integer('Invoice No')
x_net_weight = fields.Integer('Net weight')
x_gross_weight = fields.Integer('Gross Weight')
Then I tried to extend the form with the following code:
<record id="view_form_todo_task_inherited" model="ir.ui.view">
<field name="name">Test</field>
<field name="model">stock.inventory</field>
<field name="inherit_id" ref="stock.view_inventory_form"/>
<field name="arch" type="xml">
<field name="line_ids">
<field name="x_container_details"/>
<field name="x_wagon_no"/>
</field>
</field>
</record>
Odoo is not returning any error, but my fields are not showed in the (sub) tree of the form.. what am I doing wrong?
Thanks to anyone that can help with this!

Answer 1

This is not the right way to extend a view, you should take a look documentation.
You need to specify the position were you want to add or replace fields, this is an example to insert fields at the end of the list:
<record id="view_form_todo_task_inherited" model="ir.ui.view">
<field name="name">Test</field>
<field name="model">stock.inventory</field>
<field name="inherit_id" ref="stock.view_inventory_form"/>
<field name="arch" type="xml">
<!-- to insert your fields at the end of the list -->
<xpath expr="//tree/field[#name='state']" position="after" >
<field name="x_container_details"/>
<field name="x_wagon_no"/>
</xpath>
</field>
I hope this can be helpfull for you.