Thanks for the hint. Probably this is a bug, because the association is not updated correctly. Unfortunately I am not advanced enough in rails to be able to provide a patch for it.
Alexander alias MrLongleg On 5 Feb., 04:38, Frederick Cheung <[email protected]> wrote: > On Feb 4, 11:33 pm, "[email protected]" > > <[email protected]> wrote: > > I tried to user delete_if on an association: > > > class Group < ActiveRecord::Base > > has_many :memberships, :dependent => :destroy > > has_many :users, :through => :memberships > > > ... > > end > > > This is the controller method, trying to use delete_if. Although some > > elements are removed (s2 < s1), the save method does not update the > > association. > > Looks like delete_if just acts on the target array, not the > association itself (as a slight typing saver you can pass an array to > delete. > > Fred > > > > > def intersect_or_remove_group > > other_group = Group.find(params[:group_id]) > > s1 = @group.users.size > > case params[:submit] > > when "Intersect" > > @group.users.delete_if { |u| !other_group.users.include?(u) } > > when "Remove" > > @group.users.delete_if { |u| other_group.users.include?(u) } > > end > > s2 = @group.users.size > > if s2 < s1 > > @group.save > > end > > redirect_to @group > > end > > > If I rewrite it like this, it works just fine: > > > def intersect_or_remove_group > > other_group = Group.find(params[:group_id]) > > s1 = @group.users.size > > to_be_deleted = Array.new > > case params[:submit] > > when "Intersect" > > @group.users.each { |u| to_be_deleted << u if ! > > other_group.users.include?(u) } > > when "Remove" > > @group.users.each { |u| to_be_deleted << u if > > other_group.users.include?(u) } > > end > > to_be_deleted.each { |u| @group.users.delete(u) } > > s2 = @group.users.size > > if s2 < s1 > > @group.save > > end > > redirect_to @group > > end > > > Is this a bug or a feature? > > > Thanks for any help in advance > > > Regards > > > Alexander --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
