Extjs combo數據綁定與獲取

1、

配置combo：

{
                                columnWidth: .3,
                                layout: 'form',
                                border: false,
                                items: [{
                                    id: "txtP_Nation",
                                    name: "txtP_Nation",
                                    allowBlank: false,
                                    width: 130,
                                    fieldLabel: '民族',
                                    emptyText: '請選擇民族',
                                    hiddenName: 'PM_id', //真正提交時此combo的name，請一定要注意
                                    xtype: 'combo',
                                    editable: false,
                                    store: strNation,//設置數據源
                                    displayField: 'PM_Name', //顯示文本字段
                                    valueField: 'PM_id',//value值字段id
                                    mode: 'local',
                                    triggerAction: 'all',,//請設置為"all",否則默認為"query"的情況下，你選擇某個值后，再此下拉時，只出現匹配選項，如果設為"all"的話，每次下拉均顯示全部選項
                                    selectOnFocus: true,
                                    typeAhead: true
                                }]
                            }

           2、數據源：

 　　　　var strNation = new Ext.data.Store({
                proxy: new Ext.data.HttpProxy(
                    {
                        url: '../form/Ala_HomeOtherPeople.ashx?cmd=GetParmater&type=nation'
                    }
                ),
                reader: new Ext.data.JsonReader(
                    { root: 'data' },
                    [
                        { name: 'PM_id', type: 'string' },//id
                        { name: 'PM_Name', type: 'string' }//名稱
                    ]
                )
            });
            strNation.load();

編輯或修改數據時需要把要修改的數據顯示在combo中：

  strNation.load({ callback: function () {
                    Ext.getCmp("txtP_Nation").setValue(json.P_Nation);//json.P_Nation 為數據id
                }
                });

獲取combo選中的id值：

  var P_Nation = Ext.getCmp("txtP_Nation").getValue();