code: function (record) {
          var val = record.get(this.dataIndex);
  
          if(typeof val != 'string') {
              return (this.getValue().length === 0);
          }
  
          return val.toLowerCase().indexOf(this.getValue().toLowerCase()) > -1;
      }
docs: Template method that is to validate the provided Ext.data.Record
  against the filters configuration.
  @param {Ext.data.Record} record The record to validate
  @return {Boolean} true if the record is valid within the bounds
  of the filter, false otherwise.