这是一个MD风格的地址选择器的示例，非常希望以及欢迎大家提交PR来完善它，如果有喜欢的同学可以直接拿到项目中使用。
此repo的数据（json文件）放在assets，repo中的RequestCityListTask负责从assets中读取数据，你可以替换成从服务器请求数据！
Copyright 2017 Yan Zhenjie
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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