template (xmlui): added values property to be able to use always values even when there is only one value

src/tools/common/template_xmlui.py

@@ -49,6 +49,10 @@ class ValueWidget(Widget):
         super(ValueWidget, self).__init__(xmlui_parent)
         self.value = value
 
+    @property
+    def values(self):
+        return [self.value]
+
 
 class InputWidget(ValueWidget):