EXT JS 网格 控制全选监听事件

//添加监听事件  selectionchange ，举例grid.selModel.on("selectionchange",function(selModel){                         var ftCount = 0;var amt = Number(0);var rowArray = grid.getSelectionModel().getSelections();  //获取选中列 Ext.each(rowArray,function(rec){  //遍历选中列对象 amt += Number(rec.get('SETTLE_AMT'));});ftCount = rowArray.length;if(ftCount > 0){Ext.get('ftSelectMsgDIV').update("您勾选的指令条数:"+ftCount+",发生金额为:"+format(amt));     // 更新DIV 上面的内容信息 }else{Ext.get('ftSelectMsgDIV').update("");      }});