take attributes from baseField if appropriate

git-svn-id: svn://svn.cy55.de/Zope3/src/cybertools/trunk@3163 fd906abe-77d9-0310-91a1-e0d9ade77398

composer/schema/field.py

@@ -54,6 +54,7 @@ class Field(Component):
     value_type = None
 
     fieldTypeInfo = None
+    baseField = None
     instance_name = None
     display_renderer = None
     display_format = None
@@ -70,6 +71,11 @@ class Field(Component):
         for k, v in kw.items():
             setattr(self, k, v)
 
+    def __getattr__(self, attr):
+        if self.baseField is not None:
+            return getattr(self.baseField, attr)
+        raise AttributeError(attr)
+
     @property
     def name(self):
         return self.__name__