Receiving error on android (com.facebook.react.bridge.ReadableNativeMap cannot be cast to java.lang.Strin)

[jm90m]

I am currently working on a new cryptocurrency / chat mobile app using matrix sdk (https://github.com/matrix-org/matrix-js-sdk), and this fails for me on android, I receive the com.facebook.react.bridge.ReadableNativeMap cannot be cast to java.lang.String error.

• Also I'm not too sure if this works on iOS with matrix SDK, since I don't need the polyfills on iOS, I only need the polyfills on android

How to reproduce

• make browser-pollyfill a dependancy, and import it into your project
• start your project, and within a few seconds - minutes, an error will appear
• Device: Moto G5
• Operating system: Android 🤦‍♂️

Current Solution

Right now I have a file called polyfill.js and I import it only for android within App.js - contents of this file were taken from Node.js file in this library, credit goes to @EvanBacon

import { EventEmitter } from 'fbemitter';

class Document {
  constructor() {
    this.emitter = new EventEmitter();
    this.addEventListener = this.addEventListener.bind(this);
    this.removeEventListener = this.removeEventListener.bind(this);
    this._checkEmitter = this._checkEmitter.bind(this);
  }

  createElement(tagName) {
    return {};
  }

  _checkEmitter() {
    if (
      !this.emitter ||
      !(this.emitter.on || this.emitter.addEventListener || this.emitter.addListener)
    ) {
      this.emitter = new EventEmitter();
    }
  }

  addEventListener(eventName, listener) {
    this._checkEmitter();
    if (this.emitter.on) {
      this.emitter.on(eventName, listener);
    } else if (this.emitter.addEventListener) {
      this.emitter.addEventListener(eventName, listener);
    } else if (this.emitter.addListener) {
      this.emitter.addListener(eventName, listener);
    }
  }

  removeEventListener(eventName, listener) {
    this._checkEmitter();
    if (this.emitter.off) {
      this.emitter.off(eventName, listener);
    } else if (this.emitter.removeEventListener) {
      this.emitter.removeEventListener(eventName, listener);
    } else if (this.emitter.removeListener) {
      this.emitter.removeListener(eventName, listener);
    }
  }
}

window.document = window.document || new Document();

[EvanBacon]

In theory it does work in vanilla React Native but this error seems deeply rooted in GL stuff (normalize is used in a shader that isn't supported on android?). GL is really only supported in Expo, it would take a lot of time to debug this issue but I think just adding Expo will solve your issues.

[ashu777]

same here. i am getting error: Value for title cannot be cast from ReadableNativeMap to String

[Ilario17]

did you figure out how to solve?

[zelenko]

In some cases if this error appears it means instead of JS object need to pass a string: JSON.stringify(value).