Extjs Ajax 分页

var storeCpye = new Ext.data.GroupingStore({
    proxy : new Ext.data.HttpProxy({
        url : 'cxgl_cpye.app?dateTime=' + new Date().getTime() + '&subTranCode=list'
    }),
    reader : new Ext.data.JsonReader({
        root : 'hstamcx',
        totalProperty : "results",
        fields : ["zfe_hz","khbh","bankacc","fundacc","xxsdm","dxjgdm",
                  "cpdm","tazh","tajyzh","tadm","hybh","zfe","lsdjfe",
                  "cqdjfe","zhtzfe","bddjfe","fhfs","yfhfs","fhbl",
                  "zrzfe","fejg","khlb","zjtzbz","bqsy","sybl","mrcb",
                  "ljsr","wfsy","wfsydj","dtsy","glfzkl","glfje",
                  "dqglf","glfrq","gxrq","apex1","apex2","apex3"]
    })//, 
    //sortInfo : {
    //    field : 'cpdm',
    //    direction : 'DESC'
    //},
    //groupField : 'cpdm'
});

var colMArray = new Array();
colMArray = [{header : "产品代码",    dataIndex : "cpdm",    width : 100},
            {header : "代销机构代码",    dataIndex : "dxjgdm",    width : 100},
            //{header : "总份额汇总",    dataIndex : "zfe_hz",    width : 100},
            {header : "总份额",    dataIndex : "zfe",    width : 100, align:"right"}, 
           {header : "客户编号",    dataIndex : "khbh",    width : 100},
           {header : "理财账号",    dataIndex : "bankacc",    width : 100}, 
           {header : "客户资金账号",    dataIndex : "fundacc",    width : 100}, 
           {header : "本行销售商代码",    dataIndex : "xxsdm",    width : 100}, 
           {header : "TA账号",    dataIndex : "tazh",    width : 100}, 
           {header : "TA交易账号",    dataIndex : "tajyzh",    width : 100}, 
           {header : "TA代码",    dataIndex : "tadm",    width : 100}, 
           {header : "合约编号",    dataIndex : "hybh",    width : 100}, 
           {header : "临时冻结份额",    dataIndex : "lsdjfe",    width : 100, align:"right"}, 
           {header : "长期冻结份额",    dataIndex : "cqdjfe",    width : 100, align:"right"}, 
           {header : "组合投资份额",    dataIndex : "zhtzfe",    width : 100, align:"right"}, 
           {header : "本地冻结份额",    dataIndex : "bddjfe",    width : 100, align:"right"}, 
           {header : "当前分红方式",    dataIndex : "fhfs",    width : 100}, 
           {header : "原分红方式",    dataIndex : "yfhfs",    width : 100}, 
           {header : "红利比例(%)",    dataIndex : "fhbl",    width : 100}, 
           {header : "昨日总份额",    dataIndex : "zrzfe",    width : 100, align:"right"}, 
           {header : "份额所属机构",    dataIndex : "fejg",    width : 100},
           {header : "客户类别",    dataIndex : "khlb",    width : 100},
           {header : "追加投资标志",    dataIndex : "zjtzbz",    width : 100},
           {header : "本期收益",    dataIndex : "bqsy",    width : 100, align:"right"},
           {header : "收益客户比例(%)",    dataIndex : "sybl",    width : 100},
           {header : "买入成本",    dataIndex : "mrcb",    width : 100, align:"right"},
           {header : "累计收入",    dataIndex : "ljsr",    width : 100, align:"right"},
           {header : "未付收益",    dataIndex : "wfsy",    width : 100, align:"right"},
           {header : "冻结的未付收益",    dataIndex : "wfsydj",    width : 100, align:"right"},
           {header : "当天新分配收益",    dataIndex : "dtsy",    width : 100, align:"right"},
           {header : "管理费折扣率(%)",    dataIndex : "glfzkl",    width : 100},
           {header : "管理费总额",    dataIndex : "glfje",    width : 100, align:"right"},
           {header : "当前管理费",    dataIndex : "dqglf",    width : 100, align:"right"},
           {header : "管理费计算日期",    dataIndex : "glfrq",    width : 100},
           {header : "更新日期",    dataIndex : "gxrq",    width : 100}];

var colQd = new Ext.grid.ColumnModel(colMArray);
    
// GRID定义
var gridCpye = new Ext.grid.GridPanel({
    id : 'cpye_grid',
    title:'[产品余额]查询',
    height : 800,
    stripeRows : true,
    bodyStyle : '100%',
    disableSelection : true,
    cm : colQd,
    viewConfig : {
        forceFit : false
    },
    store : storeCpye,
    iconCls : 'details',
    animCollapse : true,
    trackMouseOver : false,
    loadMask : {
        msg : '正在加载[产品余额]信息，请稍侯……'
    },
    //selModel : smQd,
    selModel : new Ext.grid.RowSelectionModel({singleSelect:true}),
    tbar : ['-',new Ext.form.Label({
        text : '产品代码:'
    }),new Ext.form.TextField({
        id : 'cpdm',
        name : 'cpdm',
        width : 130
    }),'-',new Ext.form.Label({
        text : '代销机构代码:'
    }), new Ext.form.TextField({
        id : 'dxjgdm',
        name : 'dxjgdm',
        width : 130
    }), '-', {
        pressed : true,
        text : '  查    询    ',
        iconCls : 'yes',
        handler : selinfo
    },'-',new Ext.Toolbar.Fill(),'-',new Ext.form.Label({
        text : ' 查询方式:  '
    }),new Ext.form.Radio({
                            id:"cpdm_radio",  
                            name : "select_method",  
                            inputValue : "cpdm desc,dxjgdm desc",
                            checked : true,    
                            boxLabel : " 产 品  "//,  
                            //listeners : {  
                                //check : radiochange  
                            //}  
                           
                        }),  
                new Ext.form.Radio({
                            id:"dxjgdm_radio",  
                            name : "select_method",  
                            inputValue : "dxjgdm desc,cpdm desc",
                            boxLabel : "代销机构  "//,  
                            //listeners : {  
                                //check : radiochange  
                            //}  
                        }),'-'
     ],
    bbar : new Ext.PagingToolbar({
        pageSize : 20,
        store : storeCpye,
        displayInfo : true,
        emptyMsg : '没有记录'
    })
});

    private void list() throws HsException {
        String cpdm = $("cpdm_sel");
        String dxjgdm = $("dxjgdm_sel");
        String order_by = $("select_method_sel");
        String start = $("start");
        String limit = $("limit");
        int b=0,m=20;
        if(start!=null && !start.equals("")){
            b = new Integer(start);
        }
        if(limit!=null && !limit.equals("")){
            m = new Integer(limit);
        }
        //查询
        CpyeDao cpyeDao = new CpyeDao(request, response);
        String sql = cpyeDao.select(cpdm,dxjgdm,order_by);
        List<HashMap> list1 = null;
        try {
            list1 = this.findSql(new String(sql.getBytes("iso8859-1"),"UTF-8"));
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        
        
        List<HashMap> list = new ArrayList();
        for(int i = b; i < b + m && i<list1.size(); i++ ){
            list.add(list1.get(i));
        }
        
        //把list转化成Json
//        StringBuffer s = new StringBuffer("{results:"+list1.size()+",result:[");
//        for( int i=0;i< list.size();i++){
//            HashMap hm = list.get(i);
//            
//            for(int j=0;j < columns.length; j++){
//                if(j==0) s.append("{");
//                s.append(columns[j]+":""+hm.get(columns[j].toUpperCase().toString()).toString()+""");
//                if(j>0 && j<(columns.length-1) ) s.append(",");
//                if(j==(columns.length-1)) s.append("}");
//            }
//        }
//        s.append("]}");
        
//        AjaxTools.exAjax("{results:"+list1.size()+",hstamcx:"+JsonTools.agentJdbcLstToJson(list,lpDict,gbismDict)+",""+paramName+"":""+paramValue+""}",response);
        AjaxTools.exAjax("{results:"+list1.size()+",hstamcx:"+JsonTools.agentJdbcLstToJson(list,lpDict,gbismDict)+"}",response);
    }

public class AjaxTools {
    public static  void exAjax(String ajaxString,HttpServletResponse response)throws HsException{
        PrintWriter out = null;
        try{
            response.setContentType("text/html;charset=utf-8");
            response.setHeader("Cache-Control", "no-cache");
                out=response.getWriter();
                out.write(ajaxString);
                out.flush();
        }catch(Exception e){
            throw new HsException(HsErrorMsg.ERR_DEFAULT, "AJAX通讯出错!"+e.getMessage());
        }
        finally{
            out.close();
        }
    }

}