React: Calling JS function after bridge has been destroyed --- How to find which function

Question

I'm working on an update for our app. I've added a HeadlessTask and I've started seeing this warning in the console:

React: Calling JS function after bridge has been destroyed

How can I get the name of the function being executed?

Answer 1

Never found a good solution to this until recently, so thought I'd put this here in case it helps someone else. I finally got around this error by doing the following:

public class RNMyNativeModule extends ReactContextBaseModule {
   private ReactApplicationContext currentContext;

   public RNMyNativeModule(ReactApplicationContext reactContext) {
      super(reactContext);
      currentContext = reactContext;
   } 

   public void myEmitFn(String emitMe) {
     currentContext
      .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
      .emit("RNMyNativeModuleEvent", emitMe);
   }    
}

Basically, in your module constructor, make sure you capture the currentContext in it's own variable, and just use that whenever you need it. Otherwise it gets overwritten and destroyed whenever a live reload happens, and getReactApplicationContext() is not actually giving you the current context.

Answer 2

From the error message I assume you're in java (react-native Android):

When you reload on react-native, what happens behind the scenes is that the react context is getting destroyed, and a new one is being created.

That error get's thrown whenever a react-native Native Module is trying to do work, by using the old react context (the one that was valid before the reload).

The last time I saw that error it also included an explanation as to which module tried to do work by using the old context. Typically it's the RCTDeviceEventEmitter module trying to send a message to javascript.

You'll have to open logcat on Android studio and read the full error message.

p.s: If you're using react-native-navigation in your project, (after you discover which module is the trouble maker by using the logcat), make sure to search on their issues as they are heavily using the native side of react-native android, and I've seen lot's of similar issues so far.