event_state_selection

The event form and kanban cards show a state icon that opens a four-entry dropdown: In Progress, Ready for Next Stage, Blocked, and, after a divider, Cancelled. That is event_state_selection, introduced in Odoo 19 alongside the cancel value on the event model's kanban_state.

It subclasses the generic state_selection widget with its own template. Instead of colored bullets for every state, it assigns each value an icon and a color class: the neutral circle for In Progress, the green circle for Ready for Next Stage, an exclamation-circle for Blocked, and a red times-circle for Cancelled.

The options getter is stricter than the parent's: it maps a hardcoded list of the four values, in that order, looking each label up from the field's actual selection. A custom fifth value on the field would render on the button when active but never appear in the dropdown.

Events fail differently than tasks: they get canceled. Folding cancellation into the same one-click state control that handles day-to-day triage means an organizer can flag a canceled session from the kanban without opening the record, and the divider in the dropdown keeps that destructive choice visually separate from routine state flips.

The state is also computed server-side: kanban_state on event.event is a stored compute that resets as the event moves through stages, with manual writes allowed on top. The widget is the manual half of that loop; automations, stage changes and the widget all write the same field, and the icon reflects whoever acted last.

For teams running large event calendars, the practical value is the kanban footer usage: a wall of event cards where the red crosses and green circles carry the state of the whole program at a glance.

How core applies it on the event form

<field name="kanban_state" widget="event_state_selection" class="ms-auto float-end"/>

In the kanban footer

<field class="ms-1 my-auto" name="kanban_state" widget="event_state_selection"/>

Deferring the save

<field name="kanban_state" widget="event_state_selection"
       options="{'autosave': False}"/>

As with the whole state_selection family, the default is an immediate save of the entire record when a state is picked.

The widget is short, and each of its choices has a visible consequence.

Skipping super.setup() costs more than it looks. The parent's setup does two jobs: install the default color map and register the command palette entries when the descriptor passes withCommand for form views. By not calling it, this widget opts out of both. The colors it does not need, its own icon maps replace them, but the command entries are lost as a side effect, which is why events have no state hotkeys while tasks and applicants do.

The fixed order is a curation layer. super.options returns the field's selection with stage legend substitution; this widget re-maps it through the hardcoded list normal, done, blocked, cancel. The effect is a stable menu order regardless of how the selection is declared, at the price of dropping unknown values from the menu.

The label getter reformats too. It runs formatSelection over the filtered options, so when you enable the label with hide_label: False the text follows the same four-value mapping as the menu.

Dead code ships. this.dialog = useService("dialog") sits in setup with no caller in the class or template, in 19 and still on the development branch. Harmless, but a nice reminder that reading the source beats trusting it.

Odoo 20 is expected at Odoo Experience in Brussels, 24 to 26 September 2026; the development branch can change until release.

For this widget the branch is an icon migration, not a behavior change: the Font Awesome classes give way to the new oi icon font, with glyph names like error and cancel carried in data-icon attributes and a new stateIconClass getter splitting class from glyph. Order, divider, options and the missing hotkeys are all unchanged, and the unused dialog service is still there. We re-verify against the shipped release.