javascript - react-native搭建环境出错，应是模拟器环境错了??

Could not install the app on the device, read the error above for details.
Make sure you have an Android emulator running or a device connected and have
set up your Android development environment:
https://facebook.github.io/react-native/docs/android-setup.html

我已经按照好genymotion emulator 并且启动了一个模拟，此外，android studio ，virtual box 也安装好了，估计是有什么没有配置好？