Compatible with Rails 5+

Written by Chris Oliver @excid3.

This is a small gem for creating Google Calendar style 12 hour AM/PM time_select fields for Rails. It's based off of simple_time_select by tamoyal.

Just add this into your Gemfile followed by a bundle install:

gem "combined_time_select", "~> 2.0.0"

Here we have a model called Event with the start_time attribute that we will be using with combined_time_select.

Because Rails time_select fields submit separate values, there is some overhead on the controller side when we combine the fields into one. We can't rely on Rails to parse the input into a valid time anymore.

In the view you can do the following:

<%= f.time_select :start_time,
  :combined => true,
  :default => Time.now.change(:hour => 11, :min => 30),
  :minute_interval => 15,
  :time_separator => "",
  :start_hour => 10,
  :start_minute => 30,
  :end_hour => 14,
  :end_minute => 30
%>

This will create a combined time select starting at 10:30 AM and going till 2:30 PM with 15 minute intervals with a default of 11:30 AM. This will set the value for the start_time attribute on the object this form was created for.

Because combined_time_select overrides the time_select method to provide you the combined time fields, there is no need to designate a method when using libraries such as Formtastic. You will, however, need to disable the built in hour and minute labels by indicating :labels => false (though you can still give your individual field a label with :label => "Label Name") and to add in the am/pm designation for a 12 hour clock by indicating :ampm => true.

You can also pass in HTML options as a second hash argument to add attributes like data directly to the html.

<%= form.time_select :time_start, # :time_start here is the datetime object
  {
    combined: true, 
    minute_interval: 30, 
    ampm: true, 
    time_separator: "", 
    end_hour: 23, 
    include_blank: true
  }, # options
  {  
    data: { input: "true" }
  } # html_options
%>

On the controller side, we need to parse this attribute before we create a new object. combined_time_select provides a nice method for this called parse_time_select!. You can use this in your create action just before you initialize the new model:

def create
  params[:event].parse_time_select! :start_time
  @event = Event.new params[:event]
end

def update
  params[:event].parse_time_select! :start_time
  @event = Event.find(params[:event])
  if @event.update_attributes params[:event]
    ...
  end
end

And voila! You're all set.

If you would like to include a date with your time_select, you can use date_select with the same paramter name and the fields will be combined with the time.

<%= form.date_select :event_start %>
<%= form.time_select :event_start, combined: true %>

When the form gets submitted we will recieve a params hash like so:

{"utf8"=>"✓", "event"=>{"start_time(5i)"=>"10:00:00"}, "commit"=>"Save changes"}

A normal time_select wil use start_time(4i) for the hours and start_time(5i) for the minutes. The parse_time_select! will take all the start_time(Xi) fields, parse them into a Time object and set the params[:start_time] attribute to this object. The result after a parse_time_select!(attribute) looks like this:

{"utf8"=>"✓", "event"=>{"start_time"=>Fri, 23 Dec 2011 10:00:00 UTC +00:00}, "commit"=>"Save changes"}

This allows you to also seamlessly use a date_select field in combination with combined_time_select.