Trying to run my React Native app in Android emulator but it keeps throwing error:  

"**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/getting-started.html>
error spawnSync ./gradlew EACCES. Run CLI with --verbose flag for more details.**"

Tried react-native run-android, npm start, react-native start... nothing worked!!!

[![enter image description here](https://i.stack.imgur.com/Fvhvx.png)](https://i.stack.imgur.com/Fvhvx.png)

[![enter image description here](https://i.stack.imgur.com/A70XR.png)](https://i.stack.imgur.com/A70XR.png)

Am I missing out something here?? struggling with this since morning. Please help....

**Update:**  

Ran "adb devices" in terminal. Still its not working :/ Same error!!!   

[![enter image description here](https://i.stack.imgur.com/9hEEN.png)](https://i.stack.imgur.com/9hEEN.png)