Question

I want to call a javascript function that will be conditional upon a user’s response to the confirm box.

For example, I have the following anchor:

<%= link_to 'Sign Out', destroy_session_path, confirm: 'Are you sure that you would like to sign out?', method: :delete %>

Should I just abandon the unobtrusive javascript and bind my own jQuery callback to my anchor?

Or is there some magical way to pass a callback function to the Rails url helper? I did not see any discussion of callbacks in the documentation.

Answer 1

By following the link_to source, I see that the :confirm modifier is passed to the convert_options_to_data_attributes method, which points to the ujs script that is bundled with Rails these days (the unobtrusive javascript via jQuery). Here we find that ultimately the user’s response is passed to an event called confirm:complete by using the data-confirm attribute in the html.

So it appears that the answer is “no, you cannot pass a callback through the url helper”. But you can put a callback in your app/javascript to listen for this event. This seems to be the most unobtrusive way to accomplish my goal, considering that I am still letting rails handle the event prevention and propagation. I wait for all of this to happen, and then call my function.

$(document).on('confirm:complete', function (e, answer) {
  if (answer) {
    // user confirmed!
    myCallbackFunction();
  } else {
    // user canceled!
  }
});