auto_save_res_partner

Adding a child record to an unsaved parent is a recurring awkwardness in Odoo. The framework can hold the child in memory and write both together, but only when the child does not need anything the parent has not got yet, and the most common thing it has not got is a database id.

Some child records do need one. Anything that will be looked up, computed against or validated server side by parent id has to be attached to something real. On a brand new contact, that means the contact has to exist first.

This widget removes the awkwardness by saving the parent when the user clicks to add a row, and only then adding it. From the user's point of view nothing happens except that the contact is now saved.

The alternative to this widget is worse than it sounds. Without it, a user filling in a new contact and adding a child line gets either a confusing server error or a row that silently fails to link, and neither points at the real cause, which is that the contact was never saved.

The trade is that the contact is committed earlier than the user expected. On a contact form that is usually fine, because a half-filled contact is still a useful record, but it is worth knowing if your process treats the form as a draft until everything is entered.

The general pattern is worth keeping in mind for custom work: where a child needs a real parent, save on the add action rather than trying to explain the constraint to the user afterwards.

The core usage, trimmed

<field name="l10n_ar_partner_tax_ids" nolabel="1"
       colspan="2" widget="auto_save_res_partner">
  <list editable="bottom"> ... </list>
</field>

An ordinary editable child list. The only difference is what happens when the add link is clicked.

Reusing it elsewhere

<field name="my_child_ids"
       widget="auto_save_res_partner">
  <list editable="bottom"> ... </list>
</field>

Nothing in the widget is partner-specific despite its name, so any child list needing a saved parent benefits.

The ordinary child list

<field name="my_child_ids">
  <list editable="bottom"> ... </list>
</field>

Adds a row without saving, which is right whenever the child does not need a real parent id.

The whole widget is one overridden method. It awaits a save of the model's root record, then calls the parent implementation with the same arguments, so the row is added exactly as it normally would be, just afterwards.

Two consequences follow. The save is of the root record, not of the field's own record, which matters on a nested form: the outermost record is what gets committed. And because the save is awaited, a failure propagates and the row is never added, so an invalid contact produces the ordinary validation error rather than a half-created child.

What the widget does not do is equally worth noting. It does not save when an existing row is edited, it does not save after the row is filled in, and it does not intervene in deletion. Only the add action is touched.

Its name and location are slightly misleading. The file sits in the accounting module's partner bank folder, suggesting bank accounts, but the only core usage is a tax list on the contact form in an Argentinian localization. The behavior is entirely generic.

Odoo 20 is expected at Odoo Experience in Brussels, 24 to 26 September 2026. The development branch is unstable and this may still change; we re-verify the page after release.

Byte-identical. The file on the development branch matches Odoo 19 exactly, which is unsurprising for a widget with one overridden method and no props of its own.