I asked this question here:Redirecting back on errors to multi-form pages - Rails - Ruby-Forum but let me try to put it more succinctly.
Below I show a controller action controller meant to save a new item with its association. The page with the orignating form has displays of other instances of the same model type and parent and associations thereof.
If a user enters information for a fposition with a field entry that fails validation, I can't get the error messages and information back to the view.
If I just render the view, the view seems to be missing all the instance variables it needs. (instance variables only last one action I guess). If I redirect to the view action that initially rendered the view, that action creates a new object without the errors and partially completed data from the first attempt.
def create_fposition @fposition = Fposition.new(params[:fposition]) @formation = session[:formation] @coach = session[:coach] #need help here if @fposition #! Help here please...need a condition !!!
@fposition will not be nil because it an Fposition object.(a new Fposition object can be nil?) maybe you want to do @fposition.valid?