A new Flutter application.
This project is a starting point for a Flutter application.
A few resources to get you started if this is your first Flutter project:
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此demo是照着网上的的文章写的demo 仅供学习使用 不是源码本人所写 自己只是代码搬运工 自己也是初学者 原文地址：https://juejin.im/post/5bd01a176fb9a05cd676f984