android - React Native adb reverse ENOENT -

i trying react-native work android v4.2.2 (genymotion) unable test app on emulator. when ran react-native run-android, error could not run adb reverse: spawnsync

here log

js server running. running /user/pan/library/android/sdk/platform-tools/adb reverse tcp:8081 tcp:8081 not run adb reverse: spawnsync /user/pan/library/android/sdk/platform-tools/adb enoent building , installing app on device (cd android && ./gradlew installdebug...  failure: build failed exception.  * went wrong: problem occurred configuring project ':app'. > sdk directory '/user/pan/library/android/sdk' not exist.  * try: run --stacktrace option stack trace. run --info or --debug option more log output.  build failed  total time: 3.785 secs not install app on device, read error above details. make sure have android emulator running or device connected , have set android development environment: https://facebook.github.io/react-native/docs/android-setup.html 

note: in log saids sdk directory not exist, have double check have sdk installed in directory.

i found android emulator when executing adb devices

list of devices attached 192.168.56.101:5555 device 

i have tried following steps stack overflow post, still no luck https://stackoverflow.com/a/38536290/4540216

i got same issue. updated android_home env variable again worked me.

follow react-native android-setup documentation

ex:

export android_home=~/library/android/sdk