conditional statements in SimpleForm

Question

I'm making a scheduling app for my small photo business. I'm using Trent Richardson's jQuery TimePicker addon (which extends the jQueryUI dateselect): https://github.com/trentrichardson/jQuery-Timepicker-Addon because time is a critical part of scheduling an assignment.

In order to edit an existing record, I have to provide strftime formatting for the text input field which is tied to the jQuery widget (otherwise the time part won't default to the pre-existing content).

The following works great for creating a new record:

<%= f.input :starts_at, :as => :string %>

The following works great for editing an existing record. Unfortunately, the rails app blows up when I try to create a new record (which doesn't have pre-existing "starts_at" content):

<%= f.input :starts_at, :as => :string, :input_html => { :value => localize(f.object.starts_at, :format => "%m-%d-%Y %I:%M %P") } %>

I can't for the life of me figure out how to test (in the form) for pre-existing content in that field, and thereby offer the formatting or not. I would be so grateful for any suggestions.

Steve

Answer 1

I'm cautiously optimistic. This seems to be working (without the need for a custom input type) for my situation:

<% if @assignment.new_record? %>
  <%= f.input :starts_at, :as => :string %>
  <% else %>
  <%= f.input :starts_at, :as => :string, :input_html => { :value => localize(f.object.starts_at, :format => "%Y-%m-%d %I:%M %P") } %>
<% end %>

Again, with this in the assignments.js.coffee (because it has to match for the jQuery plugin to work):

dateFormat: 'yy-mm-dd',
timeFormat: 'hh:mm tt'

I had been trying to put the condition inline with the f.input statement which failed, and then I tried testing for a value in the :starts_at field, which likewise failed. Testing for whether this is a new record or not seems to be working. For my situation anyway.

Answer 2

The type of the field is probably a DateTime, which means you need to parse the string beforehand. You can do this with setter method or a before_validation filter, for example:

def starts_at=(datetime)
  begin
    write_attribute(:starts_at, DateTime.strptime(datetime, "%m-%d-%Y %I:%M %P"))
  rescue ArgumentError
  end
end

def starts_at
  begin
    self[:starts_at].strftime("%m-%d-%Y %I:%M %P")
  rescue NoMethodError
  end
end

http://ruby-doc.org/stdlib-2.0/libdoc/date/rdoc/DateTime.html#method-c-parse