Filter children with acts_as_tree

aris · June 8, 2012, 4:18pm

Hello Experts,
I have a tree of categories in this category object there is a property
called type.
the root categories have no type but the children have. so how I can get
all the roots with filled in children that have category type = ‘B’ for
instance.
I tried to run Category.roots then delete children With a category not
equal to ‘B’ but this causes a major performance problems.

how to call roots with filter children?

best regards
Ibrahim

hima4all · June 8, 2012, 6:31pm

This is how children is defined[1]:

has_many :children, class_name: name,
foreign_key: configuration[:foreign_key],
order: configuration[:order],
dependent: configuration[:dependent],
inverse_of: :parent

If you do: root.children.where(:type => yourtype) it should just work.

github.com

amerine/acts_as_tree/blob/master/lib/acts_as_tree.rb#L7


      
          require 'acts_as_tree/version'
          
          
module ActsAsTree
          
          
  if defined? Rails::Railtie
              require 'acts_as_tree/railtie'
            elsif defined? Rails::Initializer
              raise "acts_as_tree 1.0 is not compatible with Rails 2.3 or older"
            end
          
          
  def self.included(base)
              base.extend(ClassMethods)
            end
          
          
  # Specify this +acts_as+ extension if you want to model a tree structure
            # by providing a parent association and a children association. This
            # requires that you have a foreign key column, which by default is called

(acts_as_tree/lib/acts_as_tree.rb at master · amerine/acts_as_tree · GitHub)8

–
Oscar Del B.
Sent with Sparrow (http://www.sparrowmailapp.com/?sig)

hima4all · June 8, 2012, 9:11pm

On 8 June 2012 15:18, ibrahim hassan [email protected] wrote:

Hello Experts,
I have a tree of categories in this category object there is a property
called type.
the root categories have no type but the children have. so how I can get
all the roots with filled in children that have category type = ‘B’ for
instance.
I tried to run Category.roots then delete children With a category not
equal to ‘B’ but this causes a major performance problems.

how to call roots with filter children?

Not answering the question but I would avoid using a field named
‘type’. Rails expect this to be used with STI and may become confused
if it used as a normal field.

Colin

hima4all · June 11, 2012, 10:18am

Hello,
It didn’t work i want to bring all roots that a children have one type
not only one root.
something like
@categories = Category.roots
but with children condition category_type => ‘2’

Can you please help me with this.

Best regards

hima4all · June 10, 2012, 12:34am

Thanks for all your answers i will test this and give you a feedback can
i use a scope for this also?

hima4all · June 11, 2012, 4:53pm

On Jun 11, 3:18am, ibrahim hassan [email protected] wrote:

–
Posted viahttp://www.ruby-forum.com/.

I had a similar problem and this was my solution:
Migrate to the awesome_nested_sets gem. You can do this by installing
the gem, adding a couple fields to your table, and then running the
rebuild command. See the instructions here →

I call my nested_set ‘Library’ and only wanted users to see the
libraries that were either created for their company or not assigned
to any company.

I created this method in the user table:
def libraries
libraries = Library.arel_table

Library.where(libraries[:company_id].eq(nil).or(libraries[:company_id].eq(self.company_id)))
end

hima4all · June 12, 2012, 2:58pm

Hello,
thanks for your advice, however i wanted all the roots chould parent
should be always nil, but in the same time I want the children for this
roots to be filtered only with a specific type.
root1-
child1 type A
child2 type B
root2
child3 type A
Child4 type B

when i apply the filter on type A the result should be as follows:

root1
child1
root2
child3

Can someone help me with this?

best regards

hima4all · June 11, 2012, 5:04pm

On Jun 11, 3:18am, ibrahim hassan [email protected] wrote:

–
Posted viahttp://www.ruby-forum.com/.

Sorry if this is a double post but I had browser issues.

I had a similar problem and this is how I solved it.

First, switch to the awesome_nested_sets gem. After installing the
gem, you will need to add a couple fields and run a rebuild command.
See the instructions here →

My nested set is called ‘Library’ and I only wanted users to see
libraries that were either created for their company or not assigned
to any company (ie. library.company_id == user.company_id or
library.company_id == nil).

I created this user method:
def libraries
libraries = Library.arel_table

Library.where(libraries[:company_id].eq(nil).or(libraries[:company_id].eq(self.company_id)))
end

And call it from the controller using:
@libraries = current_user.libraries.order(‘lft ASC’)

In the view, I create a table and then use the jquery.treeTable.js to
created a widget that allows for easy navigation of the tree/sets.