Ext学习之7_下拉列表框

Ext.namespace("com.deng");
Ext.onReady(function(){
	var cities = [
	              [1,"长沙市"],[2,"株洲市"],[3,"湘潭市"],[4,"邵阳市"]
	             ];
	var proxy = new Ext.data.MemoryProxy(cities);
	var city = new Ext.data.Record.create([
	     {name:"cid",type:"int",mapping:0},
	     {name:"cname",type:"string",mapping:1}
	]);
	//var reader = new Ext.data.ArrayReader({},city);
	var reader = new Ext.data.ArrayReader({},[
	       {name:"cid",type:"int",mapping:0},
	       {name:"cname",type:"string",mapping:1}
	    ]);
	var store = new Ext.data.Store({
		proxy: proxy,
		reader: reader,
		autoLoad: true //即时加载数据
	});
	//store.load();
	var combobox = new Ext.form.ComboBox({
		renderTo: Ext.getBody(),
		triggerAction: "all",
		store: store,
		displayField: "cname",
		valueField: "cid",
		mode:"local",
		emptyText:"请选择湖南城市"
	});
	
	var btn = new Ext.Button({
		text: "列表框的值",
		renderTo: Ext.getBody(),
		handler: function(){
			Ext.Msg.alert("值","实际值：" + combobox.getValue() + ": 显示值：" + combobox.getRawValue());
		}
	});
});
/**
 * 备注：
 *  triggerAction: 是否开启自动查询的功能，为all表示不开启，为query表示开启，默认为query
 *  store: 数据源
 *  displayField: 关联Record的某一个逻辑列名作为显示值
 *  valueField：关联Record的某一个逻辑列名作为实际值
 *  mode:可选值有local和remote，如果数据来自本地，用local，如果数据来自远程服务器，必须用remote，默认为remote
 *  emptyText:没有选择任何选项的情况文本框的默认文字
 *  getValue(),用于返回实际值，getRawValue()用于返回显示值
 *  
 *  
 */