code: function () { 
          var f = $.jstree._focused();
          if(f && f !== this) {
            f.get_container().removeClass("jstree-focused"); 
          }
          if(f !== this) {
            this.get_container().addClass("jstree-focused"); 
            focused_instance = this.get_index(); 
          }
          this.__callback();
        }
docs: deal with focus