解决 React-Native: Android project not found. Maybe run react-native android first?

在终端运行命令react-native run-android时报错Android project not found. Maybe run react-native android first?

解决办法：

打开终端，进入到项目的根目录
执行命令 react-native upgrade
根据提示一直输入y，回车。
重新输入命令react-native run-android