fixed grid export with custom search, thanks Prasad Muley

VERSION

@@ -1 +1 @@
-Version 2.9.12-beta+timestamp.2015.01.15.09.47.52
+Version 2.9.12-beta+timestamp.2015.01.15.09.58.09

gluon/sqlhtml.py

@@ -2326,7 +2326,7 @@ class SQLFORM(FORM):
                              expcolumns.append(str(field))
 
             if export_type in exportManager and exportManager[export_type]:
-                if keywords:
+                if keywords and not callable(searchable):
                     try:
                         #the query should be constructed using searchable
                         #fields but not virtual fields
@@ -2339,6 +2339,19 @@ class SQLFORM(FORM):
                     except Exception, e:
                         response.flash = T('Internal Error')
                         rows = []
+                elif callable(searchable):
+                    #use custom_query using searchable
+                    try:
+                        #the query should be constructed using searchable
+                        #fields but not virtual fields
+                        sfields = reduce(lambda a, b: a + b,
+                            [[f for f in t if f.readable and not isinstance(f, Field.Virtual)] for t in tables])
+                        dbset = dbset(searchable(sfields, keywords))
+                        rows = dbset.select(left=left, orderby=orderby,
+                                            cacheable=True, *selectable_columns)
+                    except Exception, e:
+                        response.flash = T('Internal Error')
+                        rows = []
                 else:
                     rows = dbset.select(left=left, orderby=orderby,
                                         cacheable=True, *selectable_columns)