Application main has not been registered

Question

I have recently started to convert my react native app and running on Expo so i could test this on my actual android device. I am getting this error above. I have since then running my app using the Expo XDE. I am also running on a windows machine.

The full error message is:

]1

I figured that this has something to do with my index.js, yet here it is

import { AppRegistry } from 'react-native';
import App from './App';

AppRegistry.registerComponent('projectTARA', () => 'App');

Answer 1

The following solution worked:

AppRegistry.registerComponent('main',() => App);

Credits: Rishav Kumar

(Cannot you people just reply to mark as solve ?)

Answer 2

I came across this issue because I had previously run a React project that was not fully shut down. To fix this, I could have restarted my computer. But I chose to do this instead: (Using MacOS, should work with Linux as well, for Windows you would likely need to use Task Manager or similar):

1. Open terminal
2. Find the program that is using port 8081 by typing "lsof -i :8081". (Note this is LSOF in lowercase)
3. Look at the process ID (under the PID column)
4. Kill the process by typing "kill -9 PID" (where PID is the process ID number you found in step 3).

After killing the process you should be able to run your react-native project.