Question

Is it possible to create a

collection_select 

or

select tag 

for a

t.string

Where a user can select amongst predefined values for the string and only those values allowed to be stored in the database for the string? For example

t.string :relationship_status

And I want predefined values:

In a relationship
Single
Maried
Engaged
ETC 

Answer 1

The Simplest Thing That Could Possibly Work is along the lines of:

class Person < ActiveRecord::Base
  RELATIONSHIP_STATUSES = [
    "single",
    "in a relationship",
    "together",
    "it's complicated"
  ]

  validates :relationship_status, :inclusion => RELATIONSHIP_STATUSES
end

Then later, in the view:

collection_select(:person, :relationship_status, Person::RELATIONSHIP_STATUSES, :to_s)

This produces:

<select name="person[relationship_status]">
  <option value="single">single</option>
  <option value="in a relationship">in a relationship</option>

  ...
</select>