无法使用AjaxProxy提供参数

Question

如何在sencha touch中使用ajaxproxy提供参数？在extjs你这样做

Ext.Ajax.request({
        url: 'a.php/guest/getListGuests',
        params: {poolId: 13},
            scope: this,
            callback: function(options, success, response) {
});

我怎样才能在我的sencha触摸代码中执行此操作？

var detailPanel2 = new Ext.Panel({
        id:'detailPanel2',
        layout:'fit',
         items: [{    
            fullscreen:true,
            xtype: 'list',

            store: new Ext.data.Store({
                model: 'team',
                getGroupString : function(record) {
                    return record.get('name')[0];
                },
                proxy: new Ext.data.AjaxProxy({                        
                    url: 'a.php/guest/getListGuests',
                    extraParams: {
                        poolId: 13
                    },
                    method:'post',
                    reader: {
                            type: 'json',
                            root: 'data',
                             totalCount: 'count'
                                 }  
                }),autoLoad:true 
            }),

            sorters: [{
            property: 'name',
            direction: 'asc'
             }],
            itemTpl:'<font size="4" face="Helvetica, Arial" color="black">{name}</font>',
            grouped: true,
            onItemDisclosure : true,
                  listeners : {
              itemtap : function(record,index,item,e){
                 if (e.getTarget('.x-list-disclosure')) {
                    //Ext.Msg.alert(index);
                    var redirect = 'showpool.php'; 
                    window.location = redirect;
                 } 
                // else { Ext.Msg.alert("Item clicked!");}
               }
             }
        }]

    })

正如你在上面的代码中看到的那样，我给了params但是这不适用于extjs代码。