Module: ActionController::Helpers

Extended by:
ActiveSupport::Concern
Includes:
AbstractController::Helpers
Included in:
Base
Defined in:
lib/action_controller/metal/helpers.rb

Overview

# Action Controller Helpers

The Rails framework provides a large number of helpers for working with assets, dates, forms, numbers and model objects, to name a few. These helpers are available to all templates by default.

In addition to using the standard template helpers provided, creating custom helpers to extract complicated logic or reusable functionality is strongly encouraged. By default, each controller will include all helpers. These helpers are only accessible on the controller through ‘#helpers`

In previous versions of Rails the controller will include a helper which matches the name of the controller, e.g., ‘MyController` will automatically include `MyHelper`. You can revert to the old behavior with the following:

# config/application.rb
class Application < Rails::Application
  config.action_controller.include_all_helpers = false
end

Additional helpers can be specified using the ‘helper` class method in ActionController::Base or any controller which inherits from it.

The ‘to_s` method from the Time class can be wrapped in a helper method to display a custom message if a Time object is blank:

module FormattedTimeHelper
  def format_time(time, format=:long, blank_message="&nbsp;")
    time.blank? ? blank_message : time.to_fs(format)
  end
end

FormattedTimeHelper can now be included in a controller, using the ‘helper` class method:

class EventsController < ActionController::Base
  helper FormattedTimeHelper
  def index
    @events = Event.all
  end
end

Then, in any view rendered by ‘EventsController`, the `format_time` method can be called:

<% @events.each do |event| -%>
  <p>
    <%= format_time(event.time, :short, "N/A") %> | <%= event.name %>
  </p>
<% end -%>

Finally, assuming we have two event instances, one which has a time and one which does not, the output might look like this:

23 Aug 11:30 | Carolina Railhawks Soccer Match
N/A | Carolina Railhawks Training Workshop

Defined Under Namespace

Modules: ClassMethods

Class Attribute Summary collapse

Instance Method Summary collapse

Methods included from AbstractController::Helpers

#_helpers

Methods included from AbstractController::Helpers::Resolution

#all_helpers_from_path, #helper_modules_from_paths, #modules_for_helpers

Class Attribute Details

.helpers_pathObject

Returns the value of attribute helpers_path.



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# File 'lib/action_controller/metal/helpers.rb', line 66

def helpers_path
  @helpers_path
end

Instance Method Details

#helpersObject

Provides a proxy to access helper methods from outside the view.



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# File 'lib/action_controller/metal/helpers.rb', line 125

def helpers
  @_helper_proxy ||= view_context
end