[android] React-Native: Module AppRegistry is not a registered callable module

I'm currently trying to get the ES6 react-native-webpack-server running on an Android emulator. The difference is I've upgraded my package.json and build.grade to use react 0.18.0, and am getting this error on boot. As far as I'm aware AppRegistry is imported correctly. Even if I were to comment out the code this error still comes up. This does work on iOS without issue.

What am I doing wrong?

EDIT: After trying other boilerplates that do support 0.18.0, I'm still coming across the same issue.

restart packager worked for me. just kill react native packager and run it again.

npm start -- --reset-cache

Probably port is already in use. I face similar issue when i first run react-native run-android and then npm start. I solve it like this: First, get the id of the process running in port 8081: sudo lsof -i :8081

The one main reason of this problem could be where you would have installed a plugin and forget to link it.

try this:

react-native link

Re-run your app.

Hope this will help. Please let me know in comments. Thanks.

I had the same problem several times. The following solutions are solved my problem. I have listed out them according to complexity.

1. Restart the computer and see whether the problem is out

2. If it still exists, try to kill the process on running port usually 8080

   netstat -ano | findstr 8080

    taskkill /F /PID <PID>
   

3. If it still exists, go to 'android' directory as follow and go further

   cd android

   ./gradlew clean

and start node

npm start

then run npx react-native run android or expo stat and press 'a'

Hope you will OK with the above issues.

I had this issue - across iOS & Android, developing on Mac - after I had been fiddling with a dependency's code in the node_modules dir.

I solved it with:

rm -rf node_modules
npm i
npx pod-install ios

Which basically just re-installs your dependencies fresh.

I had the same issue on iOS and the cause for me was that my index.ios.js was incorrect (because I copy-pasted one of the examples without looking at its contents), it was ending with a module export declaration

exports.title = ...
exports.description = ...
module.exports = MyRootComponent;

Instead of the expected

AppRegistry.registerComponent('MyAppName', () => MyRootComponent);

You could have the same issue on android with the index.android.js I guess.

Hopefully this can save someone a headache. I got this error after upgrading my react-native version. Confusingly it only appeared on the android side of things.

My file structure includes an index.ios.js and an index.android.js. Both contain the code:

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

What I had to do was, in android/app/src/main/java/com/{projectName}/MainApplication.java, change index to index.android:

@Override
protected String getJSMainModuleName() {
    return "index.android"; // was "index"
}

Then in app/build/build.gradle, change the entryFile from index.js to index.android.js

project.ext.react = [
    entryFile: "index.android.js" // was index.js"
]

My issue was fixed by increasing my inotify max_user_watches:

sudo sysctl fs.inotify.max_user_watches=1280000

if you are facing this error in windows with android

open your root directory app folder and move into android folder .

     cd android 
     gradlew clean

start your app again react-native run-android

bhooom it works

In my case, my index.js just points to another js instead of my Launcher js mistakenly, which does not contain AppRegistry.registerComponent().

So, make sure the file yourindex.jspoint to register the class.

I solved this problem by doing the following:

1. cd android
2. ./gradlew clean
3. taskkill /f /im node.exe
4. uninstall app from android

I solved this issue just by adding

import { AppRegistry } from "react-native";
import App from "./App";
import { name as appName } from "./app.json";  
AppRegistry.registerComponent(appName, () => App);

to my index.js

make sure this exists in your index.js

I uninstalled it on Genymotion. Then run react-native run-android to build the app. And it worked. Do try this first before running sudo ./gradlew clean, it will save you a lot of time.

For me it was a issue with react-native dependency on next version of react package, while in my package.json the old one was specified. Upgrading my react version solved this problem.

For me just restarting the computer fixed it. (My error was "module appRegistry is not a registered callable module (calling runapplication) js engine: hermes")

Another top answer that is missing here and might have worked was just to kill node processes:

killall -9 node

[ Module AppRegistry is not registered callable module (calling runApplication) ]

I got this error in Expo because I had exported the wrong component name, e.g.

const Wonk = props => (
  <Text>Hi!</Text>
)

export default Stack;

If you are using some of the examples they might not work

Here is my version for scroll view

/**
 * Sample React Native App
 * https://github.com/facebook/react-native
 */

import React, {
  AppRegistry,
  Component,
  StyleSheet,
  Text,
  View,
  ScrollView,
  TouchableOpacity,
  Image
} from 'react-native';

class AwesomeProject extends Component {
  render() {
    return (
        <View>
          <ScrollView
            ref={(scrollView) => { _scrollView = scrollView; }}
            automaticallyAdjustContentInsets={false}
            onScroll={() => { console.log('onScroll!'); }}
            scrollEventThrottle={200}
            style={styles.scrollView}>
            {THUMBS.map(createThumbRow)}
          </ScrollView>
          <TouchableOpacity
            style={styles.button}
            onPress={() => { _scrollView.scrollTo({y: 0}); }}>
            <Text>Scroll to top</Text>
          </TouchableOpacity>
        </View>
    );
  }
}

var Thumb = React.createClass({
  shouldComponentUpdate: function(nextProps, nextState) {
    return false;
  },
  render: function() {
    return (
      <View style={styles.button}>
        <Image style={styles.img} source={{uri:this.props.uri}} />
      </View>
    );
  }
});

var THUMBS = [
'http://loremflickr.com/320/240?random='+Math.round(Math.random()*10000) + 1,
'http://loremflickr.com/320/240?random='+Math.round(Math.random()*10000) + 1,
'http://loremflickr.com/320/240?random='+Math.round(Math.random()*10000) + 1
];

THUMBS = THUMBS.concat(THUMBS); // double length of THUMBS
var createThumbRow = (uri, i) => <Thumb key={i} uri={uri} />;

var styles = StyleSheet.create({
  scrollView: {
    backgroundColor: '#6A85B1',
    height: 600,
  },
  horizontalScrollView: {
    height: 120,
  },
  containerPage: {
    height: 50,
    width: 50,
    backgroundColor: '#527FE4',
    padding: 5,
  },
  text: {
    fontSize: 20,
    color: '#888888',
    left: 80,
    top: 20,
    height: 40,
  },
  button: {
    margin: 7,
    padding: 5,
    alignItems: 'center',
    backgroundColor: '#eaeaea',
    borderRadius: 3,
  },
  buttonContents: {
    flexDirection: 'row',
    width: 64,
    height: 64,
  },
  img: {
    width: 321,
    height: 200,
  }
});

AppRegistry.registerComponent('AwesomeProject', () => AwesomeProject);

If you are using windows machine you need to do cd android then ./gradlew clean then run react-native run-android

I don't know why, but when I move AppRegistry.registerComponent from the index.js file that is included in index.android.js to reside inside index.android.js directly, it seems to work.

For me my issue was putting the wrong entry-file when bundling.

I was using App.js as my entry-file, hence the App couldn't find AppRegistry

Correct:

react-native bundle --platform android --dev false --entry-file index.js --bundle-output android/app/src/main/assets/index.android.bundle --assets-dest android/app/src/main/res/

Incorrect:

react-native bundle --platform android --dev false --entry-file App.js --bundle-output android/app/src/main/assets/index.android.bundle --assets-dest android/app/src/main/res/

For me just i linked with react native as this way : react-native link