React Native · A Framework For Building Cross Platform App

Solution 1  I was able to workaround the warning by updating  AppDelegate.m #if RCT_DEV #import <React/RCTDevLoadingView.h> #endif ... - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions { ... RCTBridge *bridge = [[RCTBridge alloc] initWithBundleURL:jsCodeLocation moduleProvider:nil launchOptions:launchOptions]; #if RCT_DEV [bridge moduleForClass:[RCTDevLoadingView class]]; #endif RCTRootView *rootView = [[RCTRootView alloc] initWithBridge:bridge moduleName:@"Test" initialProperties:nil]; ... } Solution 2 If you would put a breakpoint on the following line: RCTLogWarn ( @" RCTBridge required dispatch_sync to load %@ . This may lead to deadlocks " , _moduleClass); You can see which module/stack is re...

React Native Solution The issue can be fix by doing: Solution 1 npm add @babel/runtime npm install But we shouldn't have to do all this stuff ! Solution 2 for now since a lot of new changes are coming out, this fix worked for me: with npm: npm install --save @babel/runtime or with yarn: yarn add @babel/runtime (edited: if you're planning on waiting for the release that fixes this before releasing a new production build (like me) you can keep babel/runtime in devDependencies, but if you want to build a release build with this version of react-native, you need to put @babel/runtime in dependencies as the original poster said) if on ios you get _this._registerEvents is not a function, after a successful build do npm run start --reset-cache or react-native start --reset-cache edit: should add @babel/core, under resolutions, in package.json you may also need "babel-core": "7.0.0-bridge.0" in resolutions but this is more for react-native ...