Question

got a problem with one to one relations

I have some Matches and i want to have one score for a match.

my Match.rb

has_one :score, :dependent => :destroy

my score.rb

belongs_to :match

my scores_controller.rb

def new
@match = Match.find(params[:match_id])
@score = @match.score.new
end

def create
@match = Match.find(params[:match_id])
@score = @match.score.create(params[:score])
end

my routes.rb

resources :matches do
resources :scores
end

my scores/new.html.haml

= form_for([@match, @match.score.build]) do |f|
    = f.label :score1
    = f.text_field :score1
    %br
    = f.label :score2
    =f.text_field :score2
    %br
    = f.submit

my error that i get

undefined method `new' for nil:NilClass

i haven’t worked with one to one relations so far since I’m pretty new to RoR, any suggestions?

EDIT

edited my code to match create_score and build_score, seems to work. but now i have some kind of strange behavior.

in my score.rb

attr_accessible :score1, :score2

but when i try to invoke in my matches/show.html.haml

= @match.score.score1

i get an unknown method call or i don’t see anything at all… but if i just call

= @match.score

i get an score object returned (e.g. #)#

EDIT 2

Fix’d problem. I was calling

scores/new.haml.html

= form_for([@match, @match.create_score])

needs to be

= form_for([@match, @match.build_score])

everything works as intended.

needed to enter rails console and fetch those objects to see every :score1 :score2 was nil

Answer 1

Use build instead of new:

def new
    @match = Match.find(params[:match_id])
    @score = @match.build_score
end

Here are the docs for this: http://guides.rubyonrails.org/association_basics.html#belongs_to-build_association

Similarly, in the create method, do it like this:

def create
    @match = Match.find(params[:match_id])
    @score = @match.create_score(params[:score])
end

Docs for this: http://guides.rubyonrails.org/association_basics.html#belongs_to-create_association