使用EXTJS4，写联动的combo控件，首次选择联动效果，可以正常显示和选择。
再次切换选择‘一级’，动态加载‘二级’，数据可以正常加载，但是始终出现一个loading的遮盖层，选择不了下拉数据，奇怪的问题
Ext.create("Ext.panel.Panel",{
renderTo: document.body,
width:290,
height:220,
title:"城市三级联动",
plain: true,
margin:'30 10 0 80',
bodyStyle: "padding: 45px 15px 15px 15px;",
defaults :{
autoScroll: true,
bodyPadding: 10
},
items:[{
xtype:"combo",
name:'sheng',
id : 'sheng',
fieldLabel:'选择省',
displayField:'cname',
valueField:'id',
store:store,
triggerAction:'all',
queryMode: 'local',
selectOnFocus:true,
forceSelection: true,
allowBlank:false,
editable: true,
emptyText:'请选择省',
blankText : '请选择省',
listeners:{
select:function(combo, record,index){
try{
//userAdd = record.data.name;
var parent=Ext.getCmp('shi');
var parent1 = Ext.getCmp("qu");
parent.clearValue();
parent1.clearValue();
parent.store.load({params:{param:this.value}});
}
catch(ex){
Ext.MessageBox.alert("错误","数据加载失败。");
}
}
}
},
{
xtype:"combo",
name:'shi',
id : 'shi',
fieldLabel:'选择市',
displayField:'cname',
valueField:'id',
store:store1,
triggerAction:'all',
queryMode: 'local',
selectOnFocus:true,
forceSelection: true,
allowBlank:false,
editable: true,
emptyText:'请选择市',
blankText : '请选择市',
listeners:{
select:function(combo, record,index){
try{
//userAdd = record.data.name;
var parent = Ext.getCmp("qu");
parent.clearValue();
parent.store.load({params:{param:this.value}});
}
catch(ex){
Ext.MessageBox.alert("错误","数据加载失败。");
}
}
}
},
{
xtype:"combo",
name:'qu',
id : 'qu',
fieldLabel:'选择区',
displayField:'cname',
valueField:'id',
store:store2,
triggerAction:'all',
queryMode: 'local',
selectOnFocus:true,
forceSelection: true,
allowBlank:false,
editable: true,