[IMP] web: form: labels of several occurrences of a field

Before this commit, when the same field occurred multiple times in
a form view, all occurrences were associated with the same id, and
all occurrences of the corresponding label (if any) had the same
'for' attribute. As a consequence, besides the fact that there were
warnings in the chrome console, clicking on any occurrence of the
duplicated label focuses the first occurrence of the field.

This commit generates a unique id for each pair label/field, when
possible. However, there is a case that can't be handled
automatically: when the label isn't automatically generated (field
located outside a group, or with nolabel attribute set to "1").
Typically, in this case, there is a <label> node with "for"
attribute referencing the associated field. In this situation, the
id must be defined in the arch, and used in the "for" attribute:

  <form>
    <label for="phone"/><field name="phone"/>
    <label for="phone_2"/><field name="phone" id="phone_2"/>
  </form>

Task 2261697

1 files changed, 24 insertions, 0 deletions

diff --git a/doc/reference/views.rst b/doc/reference/views.rst
index 97d96fb7062..ee91fea5934 100644
--- a/doc/reference/views.rst
+++ b/doc/reference/views.rst
@@ -800,6 +800,9 @@ system. Available semantic components are:
 
   ``name`` (mandatory)
     the name of the field to render
+  ``id``
+    the node id. Useful when there are several occurrences of the same field in
+    the view (see ``label`` component below). Default is the field name.
   ``widget``
     fields have a default rendering based on their type
     (e.g. :class:`~odoo.fields.Char`,
@@ -871,6 +874,27 @@ system. Available semantic components are:
     for opening specific kanban view when selecting records from m2o/m2m in mobile
     environment
 
+``label``
+  when a ``field`` component isn't placed directly inside a ``group``, or when
+  its ``nolabel`` attribute is set, the field's label isn't automatically
+  displayed alongside its value. The ``label`` component is the manual alternative
+  of displaying the label of a field. Possible attributes are:
+  ``for`` (mandatory)
+    the reference to the field associated with the label. Can be either the name
+    of a field, or its id (``id`` attribute set on the ``field``). When there are
+    several occurrences of the same field in the view, and there are several
+    ``label`` components associated with these ``field`` nodes, those labels
+    must have unique ``for`` attributes (in this case referencing the ``id``
+    attribute of the corresponding ``field`` nodes).
+  ``string``
+    the label to display. Display the field's label (coming from the field
+    definition in the model) by default.
+  ``class``
+    same as for ``field`` component.
+  ``attrs``
+    same as for ``field`` component.
+
+
 Generic structure
 ~~~~~~~~~~~~~~~~~