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         $(container).append('<img src="/assets/ajax-loader.gif" class="infinite-scroller-spinner"></img>');
  18         $.ajax(src,
  19                {dataType: 'json',
  20                 type: 'GET',
  21                 data: {},
  22                 context: {container: container, src: src}}).
  23             fail(function(jqxhr, status, error) {
  24                 if (jqxhr.readyState == 0 || jqxhr.status == 0) {
  25                     message = "Cancelled."
  26                 } else if (jqxhr.responseJSON && jqxhr.responseJSON.errors) {
  27                     message = jqxhr.responseJSON.errors.join("; ");
  28                 } else {
  29                     message = "Request failed.";
  30                 }
  31                 // TODO: report this to the user.
  32                 console.log(message);
  33                 $(this.container).attr('data-infinite-content-href', this.src);
  34             }).
  35             done(function(data, status, jqxhr) {
  36                 $(this.container).find(".infinite-scroller-spinner").detach();
  37                 $(this.container).append(data.content);
  38                 $(this.container).attr('data-infinite-content-href', data.next_page_href);
  39             });
  40     }
  41 }
  42 $(document).
  43     on('ready ajax:complete', function() {
  44         $('[data-infinite-scroller]').each(function() {
  45             var $scroller = $($(this).attr('data-infinite-scroller'));
  46             if (!$scroller.hasClass('smart-scroll') &&
  47                 'scroll' != $scroller.css('overflow-y'))
  48                 $scroller = $(window);
  49             $scroller.
  50                 addClass('infinite-scroller').
  51                 data('infinite-container', this).
  52                 on('scroll', maybe_load_more_content);
  53         });
  54     });