apps/workbench/app/assets/javascripts/infinite_scroll.js

   1 function maybe_load_more_content() {
   2     var scroller = this;        // element with scroll bars
   3     var container;              // element that receives new content
   4     var src;                    // url for retrieving content
   5     var scrollHeight;
   6     scrollHeight = scroller.scrollHeight || $('body')[0].scrollHeight;
   7     if ($(scroller).scrollTop() + $(scroller).height()
   8         >
   9         scrollHeight - 50) {
  10         container = $(this).data('infinite-container');
  11         src = $(container).attr('data-infinite-content-href');
  12         if (!src)
  13             // Finished
  14             return;
  15         // Don't start another request until this one finishes
  16         $(container).attr('data-infinite-content-href', null);
  17         $.ajax(src,
  18                {dataType: 'json',
  19                 type: 'GET',
  20                 data: {},
  21                 context: {container: container, src: src}}).
  22             fail(function(jqxhr, status, error) {
  23                 if (jqxhr.readyState == 0 || jqxhr.status == 0) {
  24                     message = "Cancelled."
  25                 } else if (jqxhr.responseJSON && jqxhr.responseJSON.errors) {
  26                     message = jqxhr.responseJSON.errors.join("; ");
  27                 } else {
  28                     message = "Request failed.";
  29                 }
  30                 // TODO: report this to the user.
  31                 console.log(message);
  32                 $(this.container).attr('data-infinite-content-href', this.src);
  33             }).
  34             done(function(data, status, jqxhr) {
  35                 $(this.container).append(data.content);
  36                 $(this.container).attr('data-infinite-content-href', data.next_page_href);
  37                 $(document).trigger('ajax:complete');
  38             });
  39     }
  40 }
  41 $(document).
  42     on('ready ajax:complete', function() {
  43         $('[data-infinite-scroller]').each(function() {
  44             var $scroller = $($(this).attr('data-infinite-scroller'));
  45             if (!$scroller.hasClass('smart-scroll') &&
  46                 'scroll' != $scroller.css('overflow-y'))
  47                 $scroller = $(window);
  48             $scroller.
  49                 addClass('infinite-scroller').
  50                 data('infinite-container', this).
  51                 on('scroll', maybe_load_more_content);
  52         });
  53     });