I have this error when trying to pass parameters by link_to to another controller:
Models
class Theme < ApplicationRecord
belongs_to :category
end
class Category < ApplicationRecord
has_many :themes
end
Controller
def new
@[email protected]
@[email protected]
end
HTML
Error
Routes
Routes.rb
item.id returns value nil (i.e. has not been assigned id yet), therefore you get the error:
missing required keys: [: theme_id]
To solve it, verify that the object item is saved before; most likely you have generated the @category object and assigned the themes without saving the main object (ie with @category.new ) and, therefore, the id has not yet been generated so it has value nil .
Correcting my previous answer, the helper new_category_theme_comment_path if can receive parameters such as hash and as objects of ActiveRecord (in addition to numbers), therefore any of the following options is valid:
<!-- con hash -->
<%= link_to “show”, new_category_theme_comment_path(item.category_id, theme_id: item.id) %>
<!-- con número -->
<%= link_to “show”, new_category_theme_comment_path(item.category_id, item.id) %>
<!-- con objeto AR -->
<%= link_to “show”, new_category_theme_comment_path(item.category_id, item) %>