method

observe_field

v1.0.0 - Show latest stable - Class: ActionView::Helpers::JavaScriptHelper

observe_field(field_id, options = {})

public

Observes the field with the DOM ID specified by field_id and makes an AJAX call when its contents have changed.

Required options are:

:url: url_for-style options for the action to call when the field has changed.

Additional options are:

`:frequency:`	The frequency (in seconds) at which changes to this field will be detected. Not setting this option at all or to a value equal to or less than zero will use event based observation instead of time based observation.
`:update:`	Specifies the DOM ID of the element whose innerHTML should be updated with the XMLHttpRequest response text.
`:with:`	A JavaScript expression specifying the parameters for the XMLHttpRequest. This defaults to ‘value’, which in the evaluated context refers to the new field value.

Additionally, you may specify any of the options documented in link_to_remote.

# File actionpack/lib/action_view/helpers/javascript_helper.rb, line 338
      def observe_field(field_id, options = {})
        if options[:frequency] and options[:frequency] > 0
          build_observer('Form.Element.Observer', field_id, options)
        else
          build_observer('Form.Element.EventObserver', field_id, options)
        end
      end

observe_field

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