Native side not loading with custom AppDelegate.swift

[danielRChildrens]

Description

I am receiving the following error after converting the AppDelegate.mm to AppDelegate.swift:

Error: [Reanimated] The native part of Reanimated doesn't seem to be initialized.

AppDelegate.swift

import Foundation

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {
  var window: UIWindow?
  var bridge: RCTBridge!

  func application(_ application:UIApplication, didFinishLaunchingWithOptions launchOptions:[UIApplication.LaunchOptionsKey : Any]?) -> Bool {
    let jsCodeLocation: URL
    
    jsCodeLocation = RCTBundleURLProvider.sharedSettings().jsBundleURL(forBundleRoot: "index")

    let rootView = RCTRootView(bundleURL: jsCodeLocation, moduleName: "DigitalFrontDoor", initialProperties: nil, launchOptions: launchOptions)

    let rootViewController = UIViewController()
    rootViewController.view = rootView
    self.window = UIWindow(frame: UIScreen.main.bounds)
    self.window?.rootViewController = rootViewController
    self.window?.makeKeyAndVisible()
    
    return true
    
  }


  /// This method controls whether the `concurrentRoot`feature of React18 is turned on or off.
  ///
  /// @see: https://reactjs.org/blog/2022/03/29/react-v18.html
  /// @note: This requires to be rendering on Fabric (i.e. on the New Architecture).
  /// @return: `true` if the `concurrentRoot` feature is enabled. Otherwise, it returns `false`.
  func concurrentRootEnabled() -> Bool {
    return true
  }
}

Notes:

• The iOS build is completing successfully
• Android is working as expected
• I have tried removing the Pods, node_modules, build folders and reinstalling everything.
• I have tried restarting my computer
• Converting the AppDelegate to swift works without Reanimated
• I have followed this post for the AppDelegate swift migration (https://ospfranco.com/post/2021/07/31/migrate-rn-appdelegate-to-swift/)

Steps to reproduce

I have two Branches as follows:

• Branch 1 (reanimated): Regular AppDelegate with Reanimated, In this branch everything works as expected in both platforms
• Branch 2 (swift-app-delegate): Swift AppDelegate without Reanimated, In this branch everything works as expected in both platforms

When both branches are merged (swift-appdelegate-reanimated), getting Swift AppDelegate With Reanimated, the iOS build works, but when the app is launched I get the error:

Snack or a link to a repository

https://github.com/danielRChildrens/SwiftReanimated/tree/swift-appdelegate-reanimated

Reanimated version

3.3.0

React Native version

0.71.6

Platforms

iOS

JavaScript runtime

Hermes

Workflow

React Native (without Expo)

Architecture

Paper (Old Architecture)

Build type

Debug mode

Device

iOS simulator

Device model

iOS 16 iphone 14

Acknowledgements

Yes

[tomekzaw]

Hey @danielRChildrens, thanks for reporting this issue.

Currently, our initialization flow for iOS assumes that AppDelegate extends RCTAppDelegate. We swizzle jsExecutorFactoryForBridge method in order to call reanimated::REAInitializer(bridge) at the early stage of app startup (see RCTAppDelegate+Reanimated.mm).

Please let me know if any of the approaches below works for you:

1. Make changes to AppDelegate so that it extends RCTAppDelegate

-class AppDelegate: UIResponder, UIApplicationDelegate {
+class AppDelegate: RCTAppDelegate, UIResponder, UIApplicationDelegate {

2. Override method jsExecutorFactoryForBridge and manually call reanimated::REAInitializer(bridge)

[tapz]

@tomekzaw Could you please give more information about the approach 2? Tried to make my AppDelegate.swift to implement RCTCxxBridgeDelegate, but got error "Cannot find type 'RCTCxxBridgeDelegate' in scope". Tried to add import React, but that did not help.

[tomekzaw]

@tapz I'm a Swift beginner so I don't think I can help much in this case. Basically, you need to call reanimated::REAInitializer(bridge) function somewhere at the beginning of the initialization flow of the app.

[tapz]

@tomekzaw RCTAppDelegate does not support Swift, so probably RCTCxxBridgeDelegate doesn't either. Do you have any solution that would work with Swift? Otherwise Reanimated 3 does not work with Swift at all.

[tapz]

@tomekzaw Ok, I'll try to add it to as early as possible in the app initialization.

[tomekzaw]

@tapz We're currently working on a better solution so hopefully Reanimated 3.4.0 will no longer use this mechanism.

[tapz]

The problem is that I don't know how to call reanimated::REAInitializer(bridge) from Swift. I have the bridge object, as I instantiate it myself. But not the error is

Cannot find 'reanimated' in scope
Consecutive statements on a line must be separated by ';'
Expected expression

or if I remove reanimated::

"Cannot find type 'REAInitializer' in scope"

Probably have to write some kind of Objective-c bridge to make the call.

[tomekzaw]

Yup, reanimated::REAInitializer is a function written in Objective-C++.

[tapz]

I created a bridge, but now the app crashes to this:

Exception NSException * "[<RCTBridge 0x28357dce0> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key _callableJSModules." 0x00000002810c2e20

REAnimatedBridge.h

#import <Foundation/Foundation.h>
#import <React/RCTBridge.h>

@interface REAnimatedBridge : NSObject

- (void) rainit:(RCTBridge *)bridge;


@end

REAnimatedBridge.mpp

#import <RNReanimated/REAInitializer.h>
#import "REAnimatedBridge.h"

@implementation REAnimatedBridge

- (void) rainit:(RCTBridge *)bridge {
  reanimated::REAInitializer(bridge);
}

@end

MyApp-Bridging-Header.m

#import "REAnimatedBridge.h"

AppDelegate.swift

REAnimatedBridge().rainit(bridge)

rainit probably could be static, so there would be no need to create an instance of REAnimatedBridge.

[tomekzaw]

@tapz What do you mean by "I created a bridge"? You need to pass the same instance of bridge which has already been created by React Native.

[tapz]

@tomekzaw Since I'm not using RCTAppDelegate, I need to create the bridge myself.

guard let bridge = RCTBridge(delegate: self, launchOptions: launchOptions) else { return false }
let rootView = RCTRootView(bridge: bridge, moduleName: "MyApp", initialProperties: [:])
rootView.loadingView = loadingView
...
let rootViewController = UIViewController()
rootViewController.view = rootView
window.rootViewController = rootViewController
window.makeKeyAndVisible()

[zack2012]

@tapz try below code. It is work for me.

import UIKit
import React

class RNBaseViewController: UIViewController {

  init(moduleName: String, initialProperties: [AnyHashable : Any]? = nil) {
    hacker = RNObjcHacker()
    let bridge = RCTBridge(delegate: hacker, launchOptions: nil)!
    rootView = RCTRootView(bridge: bridge, moduleName: moduleName, initialProperties: initialProperties)
    super.init(nibName: nil, bundle: nil)
  }

  required init?(coder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
  }

  let hacker: RNObjcHacker
  let rootView: RCTRootView
  
  override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.
    addRCTRootView()
  }
    
  func addRCTRootView() {
    rootView.translatesAutoresizingMaskIntoConstraints = false
    self.view.addSubview(rootView)
    NSLayoutConstraint.activate([
      rootView.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor),
      rootView.leadingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.leadingAnchor),
      rootView.trailingAnchor.constraint(equalTo: view.safeAreaLayoutGuide.trailingAnchor),
      rootView.bottomAnchor.constraint(equalTo: view.safeAreaLayoutGuide.bottomAnchor),
    ])
  }
}

// RNObjcHacker.h file
#import <Foundation/Foundation.h>
#import <React/RCTBridge.h>

NS_ASSUME_NONNULL_BEGIN

@interface RNObjcHacker : NSObject<RCTBridgeDelegate>

@end

NS_ASSUME_NONNULL_END

// RNObjcHacker.mm file
#import "RNObjcHacker.h"
#import <React/RCTRuntimeExecutorFromBridge.h>
#import <react/renderer/runtimescheduler/RuntimeScheduler.h>
#import <React/RCTCxxBridgeDelegate.h>
#import <RCTAppSetupUtils.h>
#import <RNReanimated/REAInitializer.h>
#import <React/RCTBundleURLProvider.h>

@interface RNObjcHacker () <RCTCxxBridgeDelegate> {
  std::shared_ptr<facebook::react::RuntimeScheduler> _runtimeScheduler;
}
@end

@implementation RNObjcHacker

- (NSURL *)sourceURLForBridge:(RCTBridge *)bridge
{
#if DEBUG
  return [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index"];
#else
  return [[NSBundle mainBundle] URLForResource:@"main" withExtension:@"jsbundle"];
#endif
}

- (BOOL)runtimeSchedulerEnabled
{
  return YES;
}

#pragma mark - RCTCxxBridgeDelegate
- (std::unique_ptr<facebook::react::JSExecutorFactory>)jsExecutorFactoryForBridge:(RCTBridge *)bridge
{
  reanimated::REAInitializer(bridge);

  if (self.runtimeSchedulerEnabled) {
    _runtimeScheduler = std::make_shared<facebook::react::RuntimeScheduler>(RCTRuntimeExecutorFromBridge(bridge));
  }
  return RCTAppSetupJsExecutorFactoryForOldArch(bridge, _runtimeScheduler);
}

@end

[tapz]

@tomekzaw I updated from 3.3.0 to 3.4.1 and now reanimated::REAInitializer cannot be found.

REAnimatedBridge.mpp:15:15 No type named 'REAInitializer' in namespace 'reanimated'

[tapz]

Does not seem to require the REAInitializer call anymore...

[piaskowyk]

yes, you no longer need to call REAInitializer