Ext gird分页学习

var store = new Ext.data.Store({
                    // 使用一个URL获取数据源
                    url:  '../ListAlarminfoAfterten.form',
                                   
                   //映射关系
                    reader: new Ext.data.XmlReader({
                           record: 'tbalarminfo',
                           id: 'id',
                           totalRecords:'countRow'
                       }, [
                           {name: 'id', mapping: 'ItemAttributes > id'},
                          'id','errorid','taskname','alarmtime','descr','matter','rating','status'
                       ])
                });
                   //创建一个表格对象
                   var sm = new Ext.grid.CheckboxSelectionModel();
                    var cm = new Ext.grid.ColumnModel([
                            new Ext.grid.RowNumberer(),//自动行号
                               sm,//添加的地方
                            {header: "id", dataIndex: 'id',hidden:true},
                            {header: "错误ID", width: 100, dataIndex: 'errorid'},
                            {header: "任务名称", width: 100, dataIndex: 'taskname'},
                            {header: "时间", width: 100, dataIndex: 'alarmtime'},
                            {header: "报警描述", width: 150, dataIndex: 'descr'},
                            {header: "错误内容", width: 150, dataIndex: 'matter',hidden:true},
                            {header: "级别", width: 100, dataIndex: 'rating'},
                            {header: "状态", width: 100, dataIndex: 'status',renderer:function(value){
                                if (value == '0') {
                                    return "<span style='color:red;font-weight:bold;'>未通知</span>";
                                } else if (value == '1') {
                                    return "<span style='color:red;font-weight:bold;'>未处理</span>";
                                }else if (value == '10') {
                                    return "<span style='color:green;font-weight:bold;'>已处理</span>";
                                }
                            }}
                    ]);
                    cm.defaultSortable = true;
   
                    // create the grid
                    var grid = new Ext.grid.GridPanel({
                        el:'example-grid',
                        store: store,
                        cm: cm,
                        sm: sm,
                        width: 700,
                        height: 310,
                        fitToFrame: true,
                        title:'文件同步历史报警信息列表',
                        selModel: new Ext.grid.RowSelectionModel({singleSelect:false}),
                        bbar: new Ext.PagingToolbar({
                            pageSize: 20,
                            store: store,
                            displayInfo: true,
                            displayMsg: '显示第 {0} 条到 {1} 条记录，一共 {2} 条',
                            emptyMsg: "没有记录"
                        })
                    });
                   
                    grid.render();
                    store.load({ params : { start : 0, limit : 10 }});   
                   
                    //为grid添加双击事件做弹出窗口处理
                   
                    grid.addListener('rowdblclick',function(){
                       
                        var records = grid.getSelectionModel().getSelections();
                        var stat = records[0].get("status");
                        id=records[0].get('id');
                        errorid=records[0].get('errorid');
                        errordescr=records[0].get('descr');
                        matter=records[0].get('matter');
                        if(stat!="10"){
                                if(!records.length){
                                    alert("请选择要处理的报警信息");
                                }
                                else{
                                   
                                    window.open ('ModifyFileAlarmStatById.jsp?id='+id+","+errorid+","+errordescr+","+matter,'newwindow', 'height=300, width=540, top=200, left=200, toolbar=no, menubar=no, scrollbars=no, resizable=no,location=no, status=no');                             
                                }
                        }else{
                                window.open ('ViewAlarmDisposenoticeById.jsp?id='+id+","+errorid+","+errordescr+","+matter,'newwindow', 'height=200, width=540, top=200, left=200, toolbar=no, menubar=no, scrollbars=no, resizable=no,location=no, status=no');
                        }
                    });


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