more customization options

app/models/will_filter/filter.rb

@@ -164,22 +164,24 @@ def inner_joins
     end
 
     def model_columns
-      model_class.columns
+      @model_columns ||= model_class.columns
     end
 
     def model_column_keys
-      model_columns.collect{|col| col.name.to_sym}
+      @model_column_keys ||= model_columns.collect{|col| col.name.to_sym}
     end
 
     def contains_column?(key)
-      model_column_keys.index(key) != nil
+      model_column_keys.index(key.to_sym) != nil
     end
 
     def definition
       @definition ||= begin
         defs = {}
         model_columns.each do |col|
-          defs[col.name.to_sym] = default_condition_definition_for(col.name, col.sql_type)
+          key = col.name.to_sym
+          next unless contains_column?(key)
+          defs[key] = default_condition_definition_for(col.name, col.sql_type)
         end
         inner_joins.each do |inner_join|
           join_class = association_class(inner_join)
@@ -236,6 +238,10 @@ def default_condition_definition_for(name, sql_data_type)
       operators
     end
 
+    def model_class_for_column_key(key)
+      nil
+    end
+
     def sorted_operators(opers)
       (WillFilter::Config.operator_order & opers.keys.collect{|o| o.to_s})
     end

lib/will_filter/containers/filter_list.rb

@@ -36,30 +36,35 @@ class FilterList < WillFilter::FilterContainer
       def self.operators
         [:is_filtered_by]
       end
-    
+
       def validate
         return "Value must be provided" if value.blank?
       end
-    
+
       def template_name
         'list'
       end
 
       def linked_filter
         @linked_filter ||= begin
-          if condition.key == :id
+          model_class = filter.model_class_for_column_key(condition.key)
+
+          if model_class
+            model_class_name = model_class.name
+          elsif condition.key == :id
             model_class_name = filter.model_class_name
           else
             model_class_name = condition.key.to_s[0..-4].camelcase
           end
+
           WillFilter::Filter.new(model_class_name)
         end
       end
-    
+
       def options
         linked_filter.saved_filters(false)
       end
-    
+
       def sql_condition
         return nil unless operator == :is_filtered_by
         sub_filter = WillFilter::Filter.find_by_id(value) || linked_filter.user_filters.first
@@ -71,7 +76,7 @@ def sql_condition
           sub_conds[0] = " #{condition.full_key} IN (SELECT #{sub_filter.table_name}.id FROM #{sub_filter.table_name}) "
         else
           sub_conds[0] = " #{condition.full_key} IN (SELECT #{sub_filter.table_name}.id FROM #{sub_filter.table_name} WHERE #{sub_conds[0]}) "
-        end  
+        end
 
         sub_conds
       end