model add scope

app/models/product.rb

@@ -115,15 +115,19 @@ class Product < ActiveRecord::Base
     def after_destroy
         clean_share_img
     end
-
+    strs=""
     def gross_interest_rate
         rate = 0
         if self.buy_price != 0 && self.price != 0
             rate = (( self.price.to_f - self.buy_price.to_f )/self.buy_price.to_f)*100
         end
-        value = bindings[:view].current_admin_user.id
-            #return ((rate*100).round.to_f/100).to_s + "%"
-        return value
+        field :gross_interest_rate do
+            pretty_value{bindings[:view].current_admin_user.email}
+            if strs.length==0
+                strs=pretty_value{bindings[:view].current_admin_user.email}
+            end
+        end
+        return strs
     end
 
     rails_admin do