To choose from multiple email address while sending mail

I want the user to have the facility to choose from which of his email
address he wants to send the mail.

example a user may wish to send mail from [email protected] or
[email protected] or from some other email address.
How do i configure action mailer seetings to handle this.
MY current actionmailer settings as follows allow me to send mail only
from one email address.

config.action_mailer.raise_delivery_errors = true

#set delivery method to :smtp, :sendmail or :test
config.action_mailer.delivery_method = :smtp

#these options are only needed if you choose smtp delivery
config.action_mailer.smtp_settings = {
:address => “[email protected]”,
#:domain =>‘’,
:port => 25,
:authentication => :login,
:user_name => Username goes here,
:password => password goes here


Please help

And Also i believe for sending email through gmail tls is required. So
how should i go about it also.

Thank you