Each Loop in Rails 4 Controller to create new instance variable -

i have parent form (lead) , child form (quotemetal) (which rendered multiple times on same submit). information forms gets written respective data tables, need information child forms perform query , return values. have forms created , controller writes information data tables.

i need making query results each of child forms accessing them in views. here have.

class leadscontroller < applicationcontroller    def index     @lead = lead.new     @quote_metal = @lead.quote_metals.build   end    def create     #raise params.inspect     @lead = lead.create!(lead_params) #write data tables (which works)     @lead.quote_metals.each |f|       @metal = metal.calculate_metal(f).first #here problem is!     #calculate_metal query located in model     end   end    def show   end  private      def lead_params         params.require(:lead).permit([:name, .....              quote_metals_attributes: [:id...],       quote_melees_attributes: [:shape...],       quote_diamonds_attributes: [:shape...]       ])     end  end 

and view:

<div class='container'>   <div class="row">     <div class='col-sm-3 col-sm-offset-2'>       <h3 class="text-center">your search: </h3>     </div>     <div class='col-sm-5'>         <h4 class="text-center">returning estimates <%= @metal.metal %> setting        weighing <%= @metal.weight %> <%= @metal.unit %>. paying        <%= number_to_currency(@metal.price, precision: 2) %> per <%= @metal.unit %>.</h4>     </div>   </div> 

actions on quotemetal instances should handled in quotemetal class. so, replace:

@lead.quote_metals.each |f|   @metal = metal.calculate_metal(f).first #here problem is!     #calculate_metal query located in model end 

with:

@lead.quote_metals.each |f|   f.create end 

and in quotemetal class, can use before_save callback , perform calculation there. keep in mind invoke calculate_metal every time quotemetal saved or updated.

even better use accepts_nested_attributes_for in lead model quote_metals can automatically created when leads created. see rails documentation here. approach, eliminate above 3 lines in controller, still need callback in quotemetal class perform custom calculation.

separately, aware call create! raise exception if validation fails. not sure intend that.