# Dynamic drop down - pls help

**URL:** <https://www.ruby-forum.com/t/dynamic-drop-down-pls-help/105267>\
**Category:** Rails\
**Created:** [May 28, 2007, 9:22am UTC](https://www.ruby-forum.com/t/dynamic-drop-down-pls-help/105267 "2007-05-28T09:22:39Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![anusha18](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/3d9bf3/32.png) [@anusha18](https://www.ruby-forum.com/u/anusha18)\
**Post date:** [May 28, 2007, 9:22am UTC](https://www.ruby-forum.com/t/dynamic-drop-down-pls-help/105267/1 "2007-05-28T09:22:39Z")

</div>

002\_create\_states.rb

class CreateCities \< ActiveRecord::Migration  
def self.up  
create\_table :cities do |t|  
t.column :state\_id, :integer  
t.column :city\_name, :string  
end  
end

def self.down  
drop\_table :cities  
end  
end

001\_create\_cities.rb

class CreateCities \< ActiveRecord::Migration  
def self.up  
create\_table :cities do |t|  
t.column :state\_id, :integer  
t.column :city\_name, :string  
end  
end

def self.down  
drop\_table :cities  
end  
end

index.rhtml

\<%= javascript\_include\_tag “prototype” %\>

state

Select state \<% @states.each do |state| %\> \<%= state.state\_name %\> \<% end %\>  
city
cities

\<%= observe\_field(:state\_id,  
:update =\> “city\_id\_container”,  
:url =\> { :action =\> :index},  
:with =\> “‘state\_id=’+value”) %\>

admin\_controller.rb

class AdminController \< ApplicationController  
def index  
@cities = City.find\_all\_by\_state\_id(@params[":state\_id"])  
@html = “”  
@html += “No city”  
@cities.each do |@city|  
@html += “#{@city.city\_name}”  
end  
@html += “”  
@states = State.find(:all)  
end  
end

state.rb

class State \< ActiveRecord::Base  
has\_many :cities  
end

city.rb

class City \< ActiveRecord::Base  
belongs\_to :states  
end

can u jst tell me how can i get the values into the 2nd drop down  
list…plss

---

<div class="post-metadata">

**Author:** ![anusha18](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/3d9bf3/32.png) [@anusha18](https://www.ruby-forum.com/u/anusha18)\
**Post date:** [May 28, 2007, 12:15pm UTC](https://www.ruby-forum.com/t/dynamic-drop-down-pls-help/105267/2 "2007-05-28T12:15:56Z")

</div>

is it a copy paste error or are

001\_create\_cities.rb

and

002\_create\_states.rb

equal ?

marcel