While working on a small application for a friend of mine, I stumbled
upon a particularly tricky problem. But first a few lines about my
general setup:
Among other things, my application is managing Employees, each of which
has_and_belongs_to_many Skills. My pretty straightforward
EmployeesController offers the actions “new” and “edit”, which display a
form where the user can edit the employee record. The user is able to
assign skills to an employee by using text fields, if a skill does not
already exist, it is created on the fly when updating the employee
record.
This part of the application already works, I implemented the solution
proposed by Ryan B. in his Railscasts #73-75. Thus my Employee model
has a virtual attribute skill_attributes; in the setter method
skill_attributes=(), Skill.find_or_create_by_name() is called for each
passed skill name. My code for this is not quite elegant, but it works
just fine:
def skill_attributes=( skill_attributes )
self.skills.clear
for attributes in skill_attributes
unless attributes[ ‘name’ ].blank?
skill = Skill.find_or_create_by_name( attributes[ ‘name’ ] )
self.skills << skill unless self.skills.include?( skill )
end
end
end
In the _form for the employees I just render the following partial for
each skill:
Using the “remove” link, the user can remove the skill entry (the
with the label and the text_field), new ones can be added by a link in
the main form:
link_to_function ‘Add skill’ do |page|
page.insert_html :bottom, :skills, :partial => ‘skill’, :object =>
Skill.new
end
As mentioned above, this part is already working fine. However, I also
want to add an auto completion feature using AJAX, because this was the
motivation to use text fields in the first place (in a desktop
application, I might have used a combo box for this). Using a slightly
modified version of the auto_complete plugin, this is no problem in
other parts of the application.
But in this case I am confronted with the problem that I (obviously)
have to know the (html) id of each text field to create an
Ajax.Autocompleter for it. But at the moment, the id shared by all text
fields (“employee_skill_attributes__name”), and I have no idea about a
“clean” way of assigning an unique one to the ones created by the
client-side-only JavaScript link.
I can’t get rid of this odd feeling that the solution is waiting right
under my nose, but I am not enough of a JavaScript programmer to find a
simple way to accomplish this…
Thanks in advance!