so_template_line_o2m

A quotation template is a pre-built quote: sections, products, quantities. Odoo 19 added the idea that a whole section can be optional, meaning the customer sees it as an upsell rather than as part of the price. The convention for that is simple, a product line inside an optional section carries a quantity of zero, and this widget is what enforces the convention while the template is being edited.

It builds on the same section-and-note list that sale orders and invoices use, so sections, notes, subsections and drag-to-reorder all work the way people expect. What it adds is the optional flag, a way to toggle it on a section, coloring for those sections, and the quantity bookkeeping that has to follow every structural change.

That bookkeeping is the real content of the widget. A line can become optional or stop being optional in four different ways: by being created under a section, by being inserted from a dropdown, by the section itself being toggled, or by being dragged. Each of those paths has to end with the right quantity, and each is handled explicitly.

Optional sections are a pricing tactic with a real conversion effect. A quote that shows the core scope at a firm price, with clearly marked add-ons underneath, is easier to approve than one bundled price, and it gives the buyer something to say yes to beyond the total. Templates make that structure repeatable across a sales team instead of dependent on whoever writes the quote.

What makes it work operationally is that the zero quantity is not a manual discipline. A salesperson dragging a line into the optional block does not have to remember to zero it, and a line pulled back into scope does not stay at zero and silently drop out of the total. Both are the kind of mistake that is invisible until the customer signs a quote missing a line item.

The thing to brief a sales team on is that the quantity rewrite is automatic and does overwrite what they typed. A line moved into an optional section loses its quantity, and moving it back gives it one, not whatever it had before. For quantities that matter, set them after the line is in its final position.

The core usage

<field name="sale_order_template_line_ids"
       widget="so_template_line_o2m"
       options="{'subsections': True}">
  <form> ... </form>
</field>

Subsections are the only inherited option core turns on here. Everything else about optional sections comes from the widget.

Hiding prices in a variant of the list

<field name="line_ids" widget="so_template_line_o2m"
       options="{'subsections': True, 'hide_prices': True}"/>

hide_prices and hide_composition are inherited from the shared section list and are read in its extractor without being declared.

The fields the behavior depends on

<!-- on the child model -->
<field name="is_optional"/>       <!-- toggled on sections -->
<field name="product_uom_qty"/>  <!-- rewritten to 0 or 1 -->
<field name="display_type"/>     <!-- distinguishes structural rows -->

All three names are written literally in the widget. A model that calls them something else will render but not behave.

The interesting code is the drag-and-drop handler, because it is the only path where the widget cannot know in advance what changed. Before the drop is applied it builds a map of every row whose optional state might be affected, recording what that state is right now. After the drop it recomputes each one and issues a quantity update only where the state actually flipped: zero where a line became optional, one where a line stopped being optional and was still sitting at zero.

Which rows go into that map depends on what moved. Moving a plain line only affects that line. Moving a section is more work: dragging it upwards means every row it carries with it plus everything it passed on the way, and dragging it downwards means every row under every section between the old and new positions, with overlapping rows skipped so nothing is counted twice.

Toggling a section's optional flag is the simpler path and takes a different route: it issues one update for the section itself and one for each row underneath, setting the quantity to zero when turning optional on, and restoring it to the row's existing quantity or one when turning it off. Note the asymmetry, turning optional off restores a value, turning it on discards one.

Two smaller behaviors round it out. New lines created under an optional section get a default quantity of zero through the create context rather than through a later update, which avoids a visible flicker. And rows in an optional section are given the primary text color, which is how the section reads as optional at a glance.

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

The widget grows considerably. The development branch adds a quantity-ratio adjustment across a section, so changing a section-level quantity scales the lines under it, and publishes that helper plus the optional check into the environment for child components to call.

A unit of measure column appears in the section column set, and the renderer hides it when the underlying field is optional and not switched on, so the column does not occupy width it is not using.

The optional-section behavior described on this page is unchanged, and core still uses the widget on the quotation template form.