I need to get form only with HTML. To do this, I've used delivery callback in `hook_menu()`. This is my sample code:

    function test_menu() {
      $items['htmlform'] = array(
       'access callback'  => TRUE,
       'page callback'    => 'test_htmlform'
       'delivery callback' => 'delivery_text_plain',
       'type'             => MENU_CALLBACK,
     );
      return $items;
    }

In this form, I've used #states and #ajax. 

I've another form which is in the normal callback. I need to show htmlform into this Drupal form. So I've written a ajax callback to 'htmlform', get html, paste it into the drupal form & show this in pop up.

This is my ajax callback:

    $.ajax({
        url: '/htmlform',
        success: function(data) {
          $('#formpopup').empty();
          $('#formpopup').html(data);
          $("#form_demo_pup").modal({backdrop: 'static',keyboard: false});
          Drupal.attachBehaviors($('#form_demo_pup'));
        }
      });

Now the drupal form page have all the CSS and JavaScript but the pop up (htmlform) have only the HTML.

On this pop-up, #states and #ajax are not working since it has no Drupal form JavaScript.

How do I fix this? Even I tried "Drupal.attachBehaviors" in my custom ajax.