code: function show() {
                cancelShow();
                cancelHide();
  
                // Don't show empty tooltips.
                if (!ttScope.content) {
                  return angular.noop;
                }
  
                createTooltip();
  
                // And show the tooltip.
                ttScope.$evalAsync(function() {
                  ttScope.isOpen = true;
                  assignIsOpen(true);
                  positionTooltip();
                });
              }
docs: Show the tooltip popup element.