I have a model, Category. And I want to create an new default sub_category when ever the category is created. But I'm not sure how to do it. Here is what I have.
class Category < ActiveRecord::Base
attr_accessible :title, :position
has_many :sub_categories
after_create :make_default_sub
def make_default_sub
#Sub_Categories.new( :title=>' ');
end
end
Why not to use ancestry gem? In the future if you will have more subcategories, it will be easier to manage them.
For example in your case:
class Category < ActiveRecord::Base
attr_accessible :title, :position
has_ancestry
after_create :create_default_subcategory
def make_default_sub
children = self.children.new
children.title = ''
children.position = 1 # or autogenerated
children.save!
end
end
But can you explain, why do you need such a strange default behaviour?
Thanks
Related
I have a code that once i create the order, it will automatically fill up information for the order items (because every order has many items) but i have the error uninitialized constant Order::OrderItem. How do i solve this?
Model
class Order < ActiveRecord::Base
# attr_accessible :title, :body
attr_accessible :amount, :currency
has_many :order_items
end
class OrderItems < ActiveRecord::Base
attr_accessible :items, :order_id, :quantity
belongs_to :order
end
Controller
def checkout
#order = Order.new # Create new order
#order.total = #shopping_cart.total
#order.sub_total = #shopping_cart.subtotal
#order.sales_tax = #shopping_cart.taxes
#shopping_cart.shopping_cart_items.each do |cart_item|
#orderitems = #order.order_items.build(items: cart_item.item.name, quantity: cart_item.quantity)
end
end
uninitialized constant Order::OrderItem
The problem is with this line
class OrderItems < ActiveRecord::Base
Model class names supposed to be singular.Change OrderItems to OrderItem.And also don't forget to change the model file name as well.
Simply i have table
[product_categories]
name
and
[products]
category_id
name
if i use in product model
class Product < ActiveRecord::Base
attr_accessible :...
belongs_to :product_category
end
class ProductCategory < ActiveRecord::Base
attr_accessible :...
set_table_name "product_categories"
has_many :products
end
i can fire
product = Product.new
product.product_category
but it is possible to rename that product_category for association for example
product.category
?
If you don't need to refer to the category with product.product_category and want to use only product.category do:
class Product < ActiveRecord::Base
attr_accessible :...
belongs_to :category, class_name: 'ProductCategory'
end
How can I get the data from an associated form and insert it to the associated table from the main model?
class Supplier < ActiveRecord::Base
has_one :account, foreign_key: "acc_sup_id", :autosave => true
self.primary_key = 'sup_id'
end
class Account < ActiveRecord::Base
belongs_to :supplier, foreign_key: "acc_sup_id"
self.primary_key = 'acc_id'
self.table_name = 'accounts'
end
I am having a combined form for Supplier and Account. When I submit I need to find a way to insert the corresponding values to Supplier and Account. The problem is Supplier values is inserting properly but not Account.
I have asked the same question in several forums, groups and even in stack but nobody seems to give a convincing answer.
The basic strategy is to first look at what params are being submitted when the form is submitted. You could add a line in the controller action such as raise params.inspect to see that. Make sure that those paras contain all the data you need; if not then there is some problem in the view that generates that form.
Once you have all the data getting to the controller action, then you need to change the controller action so that is properly interprets all the data and puts it into the correct models.
I cannot give any more specific advice unless you show the code for your view, the result from doing params.inspect, and the code for the controller action that takes the data.
Try this.
Let's assume that there are orders and customers tables and that you want to perform CRUD operations on customers from orders form.
Customer model is very simple
class Customer < ActiveRecord::Base
attr_accessible :name
end
Order model must provide virtual attributes for all customer's attributes (attr_accessor construct). CRUD for customers is provided through callbacks. Validations can be used as well.
class Order < ActiveRecord::Base
attr_accessor :customer_name
attr_accessible :description, :number, :customer_name
belongs_to :customer
validates_presence_of :number
validates_presence_of :description
validates_presence_of :customer_name
before_save :save_customer
after_find :find_customer
after_destroy :destroy_customer
protected
def save_customer
if self.customer
self.customer.name = self.customer_name
else
self.customer = Customer.create(name: self.customer_name)
end
self.customer.save
end
def find_customer
self.customer_name = self.customer.name
end
def destroy_customer
self.customer.destroy
end
end
Example grid for Order model.
class Orders < Netzke::Basepack::Grid
def configure(c)
super
c.model = 'Order'
c.items = [
:description,
:number,
:customer_name
]
c.enable_edit_inline = false
c.enable_add_inline = false
end
def preconfigure_record_window(c)
super
c.form_config.klass = OrderForm
end
end
Example form for Order model.
class OrderForm< Netzke::Basepack::Form
def configure(c)
super
c.model = 'Order'
c.items = [
:description,
:number,
:customer_name
]
end
end
I am having problems to create a Rails ActiveRecord query that retrieves the first Item by unique Activity considering a creation time internal. I also need the values available in ItemStat that is why the includes.
The current method implementation is working, but it is poor and needs optimization.
This is my analogue model:
Activity:
class Activity < ActiveRecord::Base
has_many :items
end
Item:
class Item < ActiveRecord::Base
belongs_to :activity
has_one :item_stat
end
ItemStat:
class ItemStat < ActiveRecord::Base
belongs_to :item
end
Current working method (activities_id are all activities available by an user):
def self.first_items_by_unique_activity(activities_id, time_begin, time_end)
items = Item.includes(:item_stat).where(:activity_id => activities_id, :created_at => time_begin..time_end)
#make the first item unique by activity
uniques = {}
items.each do |item|
identifier = item.activity_id
uniques[identifier] = item if uniques[identifier].nil?
end
uniques.values
end
Thanks any help!
I'm trying to find an elegant (standard) way to pass the parent of a polymorphic model on to the view. For example:
class Picture < ActiveRecord::Base
belongs_to :imageable, :polymorphic => true
end
class Employee < ActiveRecord::Base
has_many :pictures, :as => :imageable
end
class Product < ActiveRecord::Base
has_many :pictures, :as => :imageable
end
The following way (find_imageable) works, but it seems "hackish".
#PictureController (updated to include full listing)
class PictureController < ApplicationController
#/employees/:id/picture/new
#/products/:id/picture/new
def new
#picture = imageable.pictures.new
respond_with [imageable, #picture]
end
private
def imageable
#imageable ||= find_imageable
end
def find_imageable
params.each do |name, value|
if name =~ /(.+)_id$/
return $1.classify.constantize.find(value)
end
end
nil
end
end
Is there a better way?
EDIT
I'm doing a new action. The path takes the form of parent_model/:id/picture/new and params include the parent id (employee_id or product_id).
I'm not sure exactly what you're trying to do but if you're trying to find the object that 'owns' the picture you should be able to use the imageable_type field to get the class name. You don't even need a helper method for this, just
def show
#picture = Picture.find(params[:id])
#parent = #picture.imagable
#=> so on and so forth
end
Update
For an index action you could do
def index
#pictures = Picture.includes(:imagable).all
end
That will instantiate all 'imagables' for you.
Update II: The Wrath of Poly
For your new method you could just pass the id to your constructor, but if you want to instantiate the parent you could get it from the url like
def parent
#parent ||= %w(employee product).find {|p| request.path.split('/').include? p }
end
def parent_class
parent.classify.constantize
end
def imageable
#imageable ||= parent_class.find(params["#{parent}_id"])
end
You could of course define a constant in your controller that contained the possible parents and use that instead of listing them in the method explicitly. Using the request path object feels a little more 'Rails-y' to me.
I just ran into this same problem.
The way I 'sort of' solved it is defining a find_parent method in each model with polymorphic associations.
class Polymorphic1 < ActiveRecord::Base
belongs_to :parent1, :polymorphic => true
def find_parent
self.parent1
end
end
class Polymorphic2 < ActiveRecord::Base
belongs_to :parent2, :polymorphic => true
def find_parent
self.parent2
end
end
Unfortunately, I can not think of a better way. Hope this helps a bit for you.
This is the way I did it for multiple nested resources, where the last param is the polymorphic model we are dealing with: (only slightly different from your own)
def find_noteable
#possibilities = []
params.each do |name, value|
if name =~ /(.+)_id$/
#possibilities.push $1.classify.constantize.find(value)
end
end
return #possibilities.last
end
Then in the view, something like this:
<% # Don't think this was needed: #possibilities << picture %>
<%= link_to polymorphic_path(#possibilities.map {|p| p}) do %>
The reason for returning the last of that array is to allow finding the child/poly records in question i.e. #employee.pictures or #product.pictures