Question

I have two models, a Charity model and a Milestone model. A charity has_many milestones.

To keep the interface a bit simpler, I’m putting the small milestone form on the show view of the Charity controller. This is fine, but when the charity model fails to save, how do i go back and render those objects with the show action so I get their invalid state?

Here’s my create action on the milestones controller. Presently I’m getting a model_name error for nil, meaning that the instance variables are likely not set.

def create
  @charity = Charity.find(params[:charity_id])
  @charity.milestones.build(params[:milestone])
  if @charity.save
    redirect_to @charity, notice: "Milestone added"
  else
    render 'charities/show'
  end
end

I know you can normally do just render action :new, but since this is across controllers, it does not work. Ideas?

Answer 1

Forgot to set the @milestone instance variable. Silly mistake. Hope this helps someone down the road.

def create
  @charity = Charity.find(params[:charity_id])
  @milestone = @charity.milestones.build(params[:milestone])    
  if @charity.save
    redirect_to @charity, notice: "Milestone added"
  else
    render 'charities/show' 
  end
end