Rails 4 - saving object with nested attributes -

i have parent model has 1 child model nested attributes. have single form updates both parent , child.

here models:

class parent < activerecord::base   has_one :child   accepts_nested_attributes_for :child end  class child < activerecord::base   belongs_to :parent end 

form view:

<%= form_for @parent, |f| %>   <%= f.text_field :parent_name %>   <%= f.fields_for @parent.child |c| %>     <%= c.text_field :child_name %>   <% end %>   <%= f.submit "save" %> <% end %> 

parent controller:

class parentscontroller < applicationcontroller         def update     @parent = parent.find(params[:id])         @parent.update(params.require(:parent).permit(:parent_name, child_attributes: [:child_name]))      redirect_to @parent   end end 

when save form, parent updates child doesn't. doing wrong?

you have problem in nested part of form code, should be

<%= form_for @parent, |f| %>   <%= f.text_field :parent_name %>   <%= f.fields_for :child |c| %>  <<<<<<<<<<< line wrong     <%= c.text_field :child_name %>   <% end %>   <%= f.submit "save" %> <% end %> 

you have pass id in params attributes :

@parent.update(params.require(:parent).permit(:parent_name, child_attributes: [:id, :child_name])) 

cheers