/selection_options_for

When a full Rails state machine is too much for your needs.This Rails plugin allows you to keep the display labels in the model when the DB holds a 1 character flag and when the code requires symbolic references to the value to use in algorithms

Primary LanguageRubyMIT LicenseMIT

SelectionOptionsFor

This code allows you to keep the display labels in the model when the DB holds only a 1 character flag. and when the code requires symbolic references to the value to use in algorithms

Note

Please see also the new 'state_objects' Gem StateObjects also supports behavior changes based on state and reduces conditional logic. https://github.com/mwindholtz/state_objects

Installation

Add this line to your application's Gemfile:

gem 'selection_options_for'

And then execute:

$ bundle

Or install it yourself as:

gem install selection_options_for

Usage

This code allows you to keep the display labels in the model when the DB holds only a 1 character flag. and when the code requires symbolic references to the value to use in algorithms

  • element 0 of the array passed in is always the logical symbol
  • 3-element Array is passed in, [key, DB value, label]
  • Removed: (2-element Array. This is no longer supported)
  • Any other type passed in throws an error

Limitations:

Don't use this if you will run reports directly against the DB In that case, the reports will not have access to the display labels

class Article < ActiveRecord::Base
        selection_options_for :file_type_option,
           [:pdf,    'P', 'PDF'],
           [:html,   'H', 'HTML'],
           [:msword, 'M', 'MS-Word']
           [:text,   'X', 'Textfile']
end

adds the following CLASS METHODS to Article

  • file_type_options returns a array of 2-value arrays suitable to fill a select tag The second example shows how to start the selection on a blank

    <%= select :article, :file_type_option, Article.file_type_options %> <%= select :article, :file_type_option, [['','']] + Article.file_type_options %>

    assert_equal ["MS-Word", "PDF", "HTML"], Article.file_type_option_hash.values assert_equal "['MS-Word', 'PDF', 'HTML']", Article.file_type_option_js_list

    file_type_option_symbols # returns hash of symbols

adds the following INSTANCE METHODS to Article

file_type_option_hash
file_type_option #  returns the single character value as in the db    
file_type_option_label  # returns the current values label    
file_type_option_symbol  # returns the current values symbol
  • methods ending in '?' return boolean if the value is set

  • methods ending in '!' set the value

    file_type_option_pdf?
    file_type_option_pdf!

    file_type_option_html? file_type_option_html!

    file_type_option_msword? file_type_option_msword!

example #1: Selection list

article = Article.new
article.file_type_option_pdf!
assert_equal 'P',   article.file_type_option
assert_equal :pdf,  article.file_type_symbol
assert_equal true,  article.file_type_option_pdf?
assert_equal 'PDF', article.file_type_option_label
assert_equal [["MS-Word", "M"], ["PDF", "P"], ["HTML", "H"]], 
            Article.file_type_options
assert_equal({"M"=>"MS-Word", "P"=>"PDF", "H"=>"HTML"}, 
               Article.file_type_option_hash) 
  
assert_equals({'P'=>:pdf, 'H'=>:html, 'W'=>:msword, 'T'=>:text},
                Article.file_type_option_symbols) 

By default the value first letter of the label is used as the one character value in the database field. When there are duplicate first letters you can specify a different letter to be stored in the database In the example below 'R' is stored in the database when 'Credit Card Account' is selected.

Example #2: Selection list

class Article < ActiveRecord::Base
 selection_options_for :payment_method_option,
     [:basic, 'B', 'Basic'],
     [:cash,  'C', 'Cash Account'],
     [:cc,    'R','Credit Card Account']
end

<%=  select :article, :payment_method_option, Article.payment_method_options %> 

Example #3: Radio button labels

<% Article.payment_method_option_hash.each do | key, value | %>
    <%=  radio_button :article, :payment_method_option, key %> <%= value %><br />
<% end %>

Example #4 in a java_script list

payment_method_option_js_list

Contributing

  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Added some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request

Thanks To

  • Scott Baron - for helping with the unit tests.