run fail

[ysq1051838264]

react-native run-android
Scanning 564 folders for symlinks in /Volumes/ms/ReactNative/JEasyCheck/node_modules (41ms)
JS server already running.
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:
https://facebook.github.io/react-native/docs/android-setup.html

[jiekesiji]

do you have resolve this problem

[xuexiaoao]

看着像是没有连接真机或者虚拟机呢