code: function applyCollapse(e) {
          var $this = $(e.target);
          var objectID = $this.attr('href');
          var expandable = $this.attr('data-expandable');
          var expanded = $this.attr("aria-expanded");
          var current = $this.closest('.pmd-accordion').attr("id");
          if (expandable === 'true') {
  			if (expanded === "true") {
  				$this.parents(Selector.PANEL).removeClass(ClassName.ACTIVE);
  			}
  			else {
  				$this.parents(Selector.PANEL).addClass(ClassName.ACTIVE);
              }
              if ($(objectID).hasClass(ClassName.IN)) {
  				$(objectID).collapse('hide');
              }
              else {
              	$(objectID).collapse('show');
              }
          } else {
              if (expanded === "true") {
                  $("#" + current + " " + Selector.ACTIVE).removeClass(ClassName.ACTIVE);
              }
              else {
                  $("#" + current + " " + Selector.ACTIVE).removeClass(ClassName.ACTIVE);
                  $this.parents(Selector.PANEL).addClass(ClassName.ACTIVE);
              }
          }
      }
docs: ------------------------------------------------------------------------
  Functions
  ------------------------------------------------------------------------