React native integrating with existing app crash: "Can't find variable: __fbBatchedBridge"

Question

I integrated react native with existing app in Android studio by Facebook guides: http://facebook.github.io/react-native/docs/embedded-app-android.html#content

I found that the error of "Can't find variable: __fbBatchedBridge" could be solved by setting dev menu. just like ReferenceError: Can't find variable: __fbBatchedBridge

But my problem is that I showed the React Native page in activity of existing app, it crashed when starting the activity with react native view.

Error log like this :

java.lang.RuntimeException: java.util.concurrent.ExecutionException: com.facebook.react.bridge.JSExecutionException: ReferenceError: Can't find variable: __fbBatchedBridge (<unknown file>:1)
     at com.facebook.react.bridge.CatalystInstanceImpl.runJSBundle(CatalystInstanceImpl.java:160)
     at com.facebook.react.ReactInstanceManagerImpl.createReactContext(ReactInstanceManagerImpl.java:779)
     at com.facebook.react.ReactInstanceManagerImpl.access$600(ReactInstanceManagerImpl.java:91)
     at com.facebook.react.ReactInstanceManagerImpl$ReactContextInitAsyncTask.doInBackground(ReactInstanceManagerImpl.java:184)
     at com.facebook.react.ReactInstanceManagerImpl$ReactContextInitAsyncTask.doInBackground(ReactInstanceManagerImpl.java:169)
     at android.os.AsyncTask$2.call(AsyncTask.java:289)
     at java.util.concurrent.FutureTask.run(FutureTask.java:237)
     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
     at java.lang.Thread.run(Thread.java:841)
     Caused by: java.util.concurrent.ExecutionException: com.facebook.react.bridge.JSExecutionException: ReferenceError: Can't find variable: __fbBatchedBridge (<unknown file>:1)
     at com.facebook.react.common.futures.SimpleSettableFuture.get(SimpleSettableFuture.java:68)
     at com.facebook.react.bridge.CatalystInstanceImpl.runJSBundle(CatalystInstanceImpl.java:136)
     at com.facebook.react.ReactInstanceManagerImpl.createReactContext(ReactInstanceManagerImpl.java:779) 
     at com.facebook.react.ReactInstanceManagerImpl.access$600(ReactInstanceManagerImpl.java:91) 
     at com.facebook.react.ReactInstanceManagerImpl$ReactContextInitAsyncTask.doInBackground(ReactInstanceManagerImpl.java:184) 
     at com.facebook.react.ReactInstanceManagerImpl$ReactContextInitAsyncTask.doInBackground(ReactInstanceManagerImpl.java:169) 
     at android.os.AsyncTask$2.call(AsyncTask.java:289) 

Answer 1

I had the same problem. Turns out as of react-native v0.21 or so, the app will crash if your server isn't running (previously it showed a red error page but still ran). Simply start your server first:

npm start

then your app should work.