[reactnative]gradlew缺乏运行权限引发的问题

Building and installing the app on the device (cd android && ./gradlew installDebug)...
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:

解决：

root@gmw-PC:/home/gmw/Desktop/app# cd android/
root@gmw-PC:/home/gmw/Desktop/app/android# chmod 777 gradlew