最好用的Android省市区三级联动选择效果

[{ 
 "name": "河北省", 
 "city": [ 
  { 
  "name": "石家庄市", 
  "area": [ 
   "长安区", 
   "桥东区", 
   "桥西区", 
   "新华区", 
   "郊 区", 
   "井陉矿区", 
   "井陉县", 
   "正定县", 
   "栾城县", 
   "行唐县", 
   "灵寿县", 
   "高邑县", 
   "深泽县", 
   "赞皇县", 
   "无极县", 
   "平山县", 
   "元氏县", 
   "赵 县", 
   "辛集市", 
   "藁", 
   "晋州市", 
   "新乐市", 
   "鹿泉市" 
  ] 
  },......] 

/** 
  * 从assert文件夹中获取json数据 
  */ 
 private void initJsonData() { 
 
  Observable.create(new ObservableOnSubscribe<List<Province>>() { 
   @Override 
   public void subscribe(ObservableEmitter<List<Province>> emitter) throws Exception { 
    List<Province> provinces = new ArrayList<>(); 
    try { 
     StringBuffer sb = new StringBuffer(); 
     InputStream is = getAssets().open("citylist.json");//打开json数据 
     byte[] by = new byte[is.available()];//转字节 
     int len = -1; 
     while ((len = is.read(by)) != -1) { 
      sb.append(new String(by, 0, len, "utf8"));//根据字节长度设置编码 
     } 
     is.close();// 关闭流 
     // 通过Gson将字符串转成对象list 
     Gson gson = new Gson(); 
     provinces = gson.fromJson(sb.toString(), new TypeToken<List<Province>>() { 
     }.getType()); 
    } catch (Exception e) { 
     e.printStackTrace(); 
    } finally { 
     emitter.onNext(provinces); 
    } 
   } 
  }).subscribeOn(Schedulers.io()) 
    .observeOn(AndroidSchedulers.mainThread()) 
    .subscribe(new Consumer<List<Province>>() { 
     @Override 
     public void accept(List<Province> provinces) throws Exception { 
      if (provinces != null && provinces.size() > 0) { 
       RegionSelectActivity.this.provinces = provinces; 
       // 显示数据 
       showData(); 
      } 
     } 
    }); 
 }

/** 
  * 展示数据 
  */ 
 private void showData() { 
  for (Province province : provinces) { 
   provinceList.add(province.getName()); 
  } 
  // 显示省份数据 
  spProvince.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, provinceList)); 
  spProvince.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { 
   @Override 
   public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { 
    provincePosition = position; 
    provinceName = provinceList.get(position); 
    // 获取当前省份对应的城市list 
    cityList.clear(); 
    List<Province.CityBean> cityBeans = provinces.get(position).getCity(); 
    for (Province.CityBean city : cityBeans) { 
     cityList.add(city.getName()); 
    } 
    // 刷新城市列表 
    spCity.setSelection(0); 
    cityName = cityList.get(0); 
    cityAdapter.notifyDataSetChanged(); 
 
    // 刷新城区列表 
    updateArea(0); 
   } 
 
   @Override 
   public void onNothingSelected(AdapterView<?> parent) { 
 
   } 
  }); 
 
  // 显示城市数据 
  spCity.setAdapter(cityAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, cityList)); 
  spCity.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { 
   @Override 
   public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { 
    cityPosition = position; 
    cityName = cityList.get(position); 
    // 刷新城区列表 
    updateArea(position); 
   } 
 
   @Override 
   public void onNothingSelected(AdapterView<?> parent) { 
 
   } 
  }); 
 
  // 显示城区数据 
  spArea.setAdapter(areaAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, areaList)); 
  spArea.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { 
   @Override 
   public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { 
    areaName = areaList.get(position); 
   } 
 
   @Override 
   public void onNothingSelected(AdapterView<?> parent) { 
 
   } 
  });