diff --git a/tryton/gui/window/view_form/view/form_gtk/many2many.py b/tryton/gui/window/view_form/view/form_gtk/many2many.py
index 46e96b3b85..b26edfecc9 100644
--- a/tryton/gui/window/view_form/view/form_gtk/many2many.py
+++ b/tryton/gui/window/view_form/view/form_gtk/many2many.py
@@ -72,7 +72,7 @@ class Many2Many(WidgetInterface):
         self.widget.pack_start(frame, expand=False, fill=True)
 
         self.screen = Screen(attrs['relation'],
-            view_ids=attrs.get('view_ids').split(','),
+            view_ids=attrs.get('view_ids', '').split(','),
             mode=['tree'], views_preload=attrs.get('views', {}),
             row_activate=self._on_activate)
         self.screen.signal_connect(self, 'record-message', self._sig_label)
diff --git a/tryton/gui/window/view_form/view/form_gtk/many2one.py b/tryton/gui/window/view_form/view/form_gtk/many2one.py
index adc18c80f8..ffb7f4d790 100644
--- a/tryton/gui/window/view_form/view/form_gtk/many2one.py
+++ b/tryton/gui/window/view_form/view/form_gtk/many2one.py
@@ -160,7 +160,7 @@ class Many2One(WidgetInterface):
 
                 WinSearch(model, callback, sel_multi=False,
                     ids=ids, context=context, domain=domain,
-                    view_ids=self.attrs.get('view_ids').split(','),
+                    view_ids=self.attrs.get('view_ids', '').split(','),
                     views_preload=self.attrs.get('views', {}))
                 return
         self.focus_out = True
@@ -172,7 +172,7 @@ class Many2One(WidgetInterface):
         domain = self.field.domain_get(self.record)
         context = self.field.context_get(self.record)
         return Screen(self.get_model(), domain=domain, context=context,
-            mode=['form'], view_ids=self.attrs.get('view_ids').split(','),
+            mode=['form'], view_ids=self.attrs.get('view_ids', '').split(','),
             views_preload=self.attrs.get('views', {}), readonly=self._readonly)
 
     def sig_new(self, *args):
@@ -250,7 +250,7 @@ class Many2One(WidgetInterface):
                 self.changed = True
             WinSearch(model, callback, sel_multi=False,
                 ids=ids, context=context, domain=domain,
-                view_ids=self.attrs.get('view_ids').split(','),
+                view_ids=self.attrs.get('view_ids', '').split(','),
                 views_preload=self.attrs.get('views', {}))
             return
         self.focus_out = True
diff --git a/tryton/gui/window/win_form.py b/tryton/gui/window/win_form.py
index c7452dc43f..0b1c23e376 100644
--- a/tryton/gui/window/win_form.py
+++ b/tryton/gui/window/win_form.py
@@ -282,7 +282,7 @@ class WinForm(NoModal):
         if len(ids) != 1:
             WinSearch(model_name, callback, sel_multi=True,
                 ids=ids, context=context, domain=domain,
-                view_ids=self.attrs.get('view_ids').split(','),
+                view_ids=self.attrs.get('view_ids', '').split(','),
                 views_preload=self.attrs.get('views', {}))
         else:
             callback(ids)