extjs中grid的单击行或者双击行事件

var onrowdoubleclick = function(grid, index, e){

         var selectionModel = grid.getSelectionModel();    

            var record = selectionModel.getSelected();

         alert(record.get('ID'));

    }

    grid_form.addListener('rowdblclick', onrowdoubleclick);

单选也是同样的方法。