Rails: Accessing data of other SQL table in View - sql

Question

I don't understand how access data from my View in other table.
I have few models. First is User, second is UsersPreferences. So i have settings page for users and code looks like this:
<%= render 'shared/error_messages', :object => f.object %>
<div class="field">
<%= f.label :name %><br />
<%= f.text_field :name %>
</div>
...
<div class="checkbox">
<%= f.check_box :notification_about_new_followers %>
<%= f.label 'Notify via email about new followers' %><br />
</div>
This code works (User has row notification_about_new_followers) but i want to change it. I decided that better way is keep preferences in other table. So i created model UsersPreferences which has user_id and flag 'notify_about_new_followers'. I tried to rewrite my view like that:
<%= render 'shared/error_messages', :object => f.object %>
<div class="field">
<%= f.label :name %><br />
<%= f.text_field :name %>
</div>
...
<div class="checkbox">
<%= f.check_box UsersPreferences.find_by_user_id(#user.id).notify_about_new_followers %>
<%= f.label 'Notify via email about new followers' %><br />
</div>
But when i visit page with code i get such error
undefined method `true' for #<User:0x007f8ac180dee8>
How can i solve this error?
User model:
class User < ActiveRecord::Base
attr_accessible :name, ... , :notification_about_new_followers
...
has_one :users_preferences
end
UsersPreferences model:
class UsersPreferences < ActiveRecord::Base
belongs_to :user, :class_name => "User"
attr_accessible :notify_about_new_followers
end

Answer 1

This line:
<%= f.check_box UsersPreferences.find_by_user_id(#user.id).notify_about_new_followers %>
is causing the error. UsersPreferences.find_by_user_id(#user.id).notify_about_new_followers is true, so essentially that line reads:
<%= f.check_box true %>
And like the error says, there is no 'true' attribute for your UserPreferences model.
To fix this you'll need to first read up on MVC (Model-View-Controller). Without knowing how MVC works, you'll never be able to move forward with Rails. There are a lot of great resources out there, just google "Model View Controller for rails". Here is a good one. A little goofy, though... if that's not your style, try another link.
After you have learned that, look up the rails helper fields_for, and there you will find your answer.