OK,i finish at last.

=======like this===========

var lastSelectId=1

…

…

subGrid: true,

subGridRowExpanded: function(subgrid_id, row_id) {

$(“#”+subgrid_id).html(“aaaaaaaa”);

},

onSelectRow: function(id){

$(“#list4”).collapseSubGridRow(lastSelectId);

$(“#list4”).expandSubGridRow(id);

lastSelectId=id;

},