Make sure you have an Android emulator running or a device connected and have

I tried to run the react-native run-android through my React Project. After that, I got an error like the following.

Total time: 14.888 secs
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

I installed Android SDK and set Android Home and Path Environmental Variable successfully. But I am still getting the same error.

I also installed Gennymotion on my pc for creating virtual android device.