Separate date and time form fields in Rails

Question

I have an ActiveRecord model Eventwith a datetime column starts_at. I would like to present a form, where date and time for starts_at

Answer 1

Using a date_select and time_select is a good way to go.

However, I wanted a text_field for the date (so I can use a JavaScript date picker).

Using strong_parameters or Rails 4+:

models/event.rb

# Add a virtual attribute
attr_accessor :start_at_date

views/events/_form.html.haml

- # A text field for the date, and time_select for time
= f.label :start_at
= f.text_field :start_at_date, value: (f.object.start_at.present? ? f.object.start_at.to_date : nil)
= f.time_select :start_at, :ignore_date => true

controllers/events_controller.rb

# If using a date_select, time_select, datetime_select
# Rails expects multiparameter attributes
# Convert the date to the muiltiparameter parts
def event_params
  if !!params[:event] && (params[:event]["start_at(4i)"].present? || params[:event]["start_at(5i)"].present?)

    if params[:event][:start_at_date].present?
      start_at_date = params[:event][:start_at_date]
    else
      start_at_date = Date.today
    end
    year  = start_at_date.match(/^(\d{4})[\-\/]/)[1]
    month = start_at_date.match(/[\-\/](\d{2})[\-\/]/)[1]
    day   = start_at_date.match(/[\-\/](\d{2})$/)[1]
    params[:event]["start_at(1i)"] = year
    params[:event]["start_at(2i)"] = month
    params[:event]["start_at(3i)"] = day
  end
  ...