code: function() {
          var self = this;
          this.$main.on('validate', 'td[editable]', function(e, newValue) {
              var columIndex = $(this).parent().find('td').index($(this));
              if (self.options.selectable) {
                  columIndex = columIndex - 1;
              }
              return self.options.onValidate.call(self, {
                  newValue: newValue,
                  field: self.options.column[columIndex].field
              }, e);
          });
      }
docs: 绑定验证事件
  @private