背景：同一個模組，兩組開發人員對同一個模型的form檢視進行了二開。在沒有指定外部ID的情況下，odoo是如何選擇展示展示哪個檢視呢？

上乾貨

  1. odoo在載入檢視的時候，首先呼叫的models.py中的load_views函式；
  1.     @api.model
  2.     def load_views(self, views, options=None):
  3.         """ Returns the fields_views of given views, along with the fields of
  4.             the current model, and optionally its filters for the given action.
  6.         :param views: list of [view_id, view_type]
  7.         :param options['toolbar']: True to include contextual actions when loading fields_views
  8.         :param options['load_filters']: True to return the model's filters
  9.         :param options['action_id']: id of the action to get the filters
  10.         :return: dictionary with fields_views, fields and optionally filters
  11.         """
  12.         options = options or {}
  13.         result = {}
  15.         toolbar = options.get('toolbar')
  16.         result['fields_views'] = {
  17.             v_type: self.fields_view_get(v_id, v_type if v_type != 'list' else 'tree',
  18.                                          toolbar=toolbar if v_type != 'search' else False)
  19.             for [v_id, v_type] in views
  20.         }
  21.         result['fields'] = self.fields_get()
  23.         if options.get('load_filters'):
  24.             result['filters'] = self.env['ir.filters'].get_filters(self._name, options.get('action_id'))
  26.         return result
  1. 上面的核心在fields_view_get函式，如下，擷取重要的內容
  1.    @api.model
  2.    def fields_view_get(self, view_id=None, view_type='form', toolbar=False, submenu=False):
  3.        self.check_access_rights('read')
  4.        view = self.env['ir.ui.view'].sudo().browse(view_id)
  6.        # Get the view arch and all other attributes describing the composition of the view
  7.        result = self._fields_view_get(view_id=view_id, view_type=view_type, toolbar=toolbar, submenu=submenu)
  8.        ···
  1. 檢查許可權通過後，呼叫_fields_view_get函式，若使用者呼叫的檢視沒有指定檢視ID，那麼將呼叫預設的檢視
  1.     @api.model
  2.     def _fields_view_get(self, view_id=None, view_type='form', toolbar=False, submenu=False):
  3.         View = self.env['ir.ui.view'].sudo()
  4.         result = {
  5.             'model': self._name,
  6.             'field_parent': False,
  7.         }
  9.         # try to find a view_id if none provided
  10.         if not view_id:
  11.             # <view_type>_view_ref in context can be used to overrride the default view
  12.             view_ref_key = view_type + '_view_ref'
  13.             view_ref = self._context.get(view_ref_key)
  14.             if view_ref:
  15.                 if '.' in view_ref:
  16.                     module, view_ref = view_ref.split('.', 1)
  17.                     query = "SELECT res_id FROM ir_model_data WHERE model='ir.ui.view' AND module=%s AND name=%s"
  18.                     self._cr.execute(query, (module, view_ref))
  19.                     view_ref_res = self._cr.fetchone()
  20.                     if view_ref_res:
  21.                         view_id = view_ref_res[0]
  22.                 else:
  23.                     _logger.warning('%r requires a fully-qualified external id (got: %r for model %s). '
  24.                         'Please use the complete `module.view_id` form instead.', view_ref_key, view_ref,
  25.                         self._name)
  27.             if not view_id:
  28.                 # otherwise try to find the lowest priority matching ir.ui.view
  29.                 view_id = View.default_view(self._name, view_type)
  31.         if view_id:
  32.             # read the view with inherited views applied
  33.             root_view = View.browse(view_id).read_combined(['id', 'name', 'field_parent', 'type', 'model', 'arch'])
  34.             result['arch'] = root_view['arch']
  35.             result['name'] = root_view['name']
  36.             result['type'] = root_view['type']
  37.             result['view_id'] = root_view['id']
  38.             result['field_parent'] = root_view['field_parent']
  39.             result['base_model'] = root_view['model']
  40.         else:
  41.             # fallback on default views methods if no ir.ui.view could be found
  42.             try:
  43.                 arch_etree = getattr(self, '_get_default_%s_view' % view_type)()
  44.                 result['arch'] = etree.tostring(arch_etree, encoding='unicode')
  45.                 result['type'] = view_type
  46.                 result['name'] = 'default'
  47.             except AttributeError:
  48.                 raise UserError(_("No default view of type '%s' could be found !", view_type))
  49.         return result
  1. 此處我們討論的是odoo是如何取預設檢視的，再進ir.ui.view模型的default_view函式檢視
  1.     @api.model
  2.     def default_view(self, model, view_type):
  3.         """ Fetches the default view for the provided (model, view_type) pair:
  4.          primary view with the lowest priority.
  6.         :param str model:
  7.         :param int view_type:
  8.         :return: id of the default view of False if none found
  9.         :rtype: int
  10.         """
  11.         domain = [('model', '=', model), ('type', '=', view_type), ('mode', '=', 'primary')]
  12.         return self.search(domain, limit=1).id
  1. 是不是很驚喜，毛都沒有，看不出來如何做的選擇。彆著急，看ir.ui.view的模型吧。

有點坑啊，大家在檢視繼承的時候。權重基本上是預設的，也就是說若不考慮name的影響，那麼預設檢視將永遠是最先新增的基礎檢視。但是，這裡name的排序居然還在ID的前面，這就有的玩了嘛，起名字也是門藝術了。

  1. 好了迴歸正題，在步驟3中，拿到了預設檢視後，我們取到的檢視有可能是繼承檢視，也有可能是基礎檢視。那麼將通過read_combined函式拼接出來以基礎檢視為框架，包含所有繼承檢視內容的etree物件。

  2.     def read_combined(self, fields=None):
  3.         """
  4.         Utility function to get a view combined with its inherited views.
  6.         * Gets the top of the view tree if a sub-view is requested
  7.         * Applies all inherited archs on the root view
  8.         * Returns the view with all requested fields
  9.           .. note:: ``arch`` is always added to the fields list even if not
  10.                     requested (similar to ``id``)
  11.         """
  12.         # introduce check_view_ids in context
  13.         if 'check_view_ids' not in self._context:
  14.             self = self.with_context(check_view_ids=[])
  16.         check_view_ids = self._context['check_view_ids']
  18.         # if view_id is not a root view, climb back to the top.
  19.         root = self
  20.         while root.mode != 'primary':
  21.             # Add inherited views to the list of loading forced views
  22.             # Otherwise, inherited views could not find elements created in their direct parents if that parent is defined in the same module
  23.             check_view_ids.append(root.id)
  24.             root = root.inherit_id
  26.         # arch and model fields are always returned
  27.         if fields:
  28.             fields = list({'arch', 'model'}.union(fields))
  30.         # read the view arch
  31.         [view_data] = root.read(fields=fields)
  32.         view_arch = etree.fromstring(view_data['arch'].encode('utf-8'))
  33.         if not root.inherit_id:
  34.             if self._context.get('inherit_branding'):
  35.                 view_arch.attrib.update({
  36.                     'data-oe-model': 'ir.ui.view',
  37.                     'data-oe-id': str(root.id),
  38.                     'data-oe-field': 'arch',
  39.                 })
  40.             arch_tree = view_arch
  41.         else:
  42.             if self._context.get('inherit_branding'):
  43.                 root.inherit_branding(view_arch)
  44.             parent_view = root.inherit_id.read_combined(fields=fields)
  45.             arch_tree = etree.fromstring(parent_view['arch'])
  46.             arch_tree = self.browse(parent_view['id']).apply_inheritance_specs(arch_tree, view_arch)
  48.         # and apply inheritance
  49.         arch = root.apply_view_inheritance(arch_tree, self.model)
  51.         return dict(view_data, arch=etree.tostring(arch, encoding='unicode'))

結束