I'm trying to implement background tasks in iOS using the react-native-background-fetch package. When I manually trigger a background fetch from Xcode (Debug > Simulate Background Fetch), the event works correctly. However:
On a real device, the background fetch event does not trigger automatically after 15 minutes. In the iOS simulator, the event does not trigger automatically—I have to manually trigger it from Xcode.
Additionally, I receive the following message:
"The operation couldn’t be completed. Background procssing task was not registered in AppDelegate didFinishLaunchingWithOptions. See iOS Setup Guide."
my AppDelegate.mm
#import "AppDelegate.h"
#import <React/RCTBridge.h>
#import <React/RCTBundleURLProvider.h>
#import <React/RCTRootView.h>
#import <React/RCTAppSetupUtils.h>
#import <TSBackgroundFetch/TSBackgroundFetch.h>
enter code here
#if RCT_NEW_ARCH_ENABLED
#import <React/CoreModulesPlugins.h>
#import <React/RCTCxxBridgeDelegate.h>
#import <React/RCTFabricSurfaceHostingProxyRootView.h>
#import <React/RCTSurfacePresenter.h>
#import <React/RCTSurfacePresenterBridgeAdapter.h>
#import <ReactCommon/RCTTurboModuleManager.h>
#import <react/config/ReactNativeConfig.h>
static NSString *const kRNConcurrentRoot = @"concurrentRoot";
@interface AppDelegate () <RCTCxxBridgeDelegate, RCTTurboModuleManagerDelegate> {
RCTTurboModuleManager *_turboModuleManager;
RCTSurfacePresenterBridgeAdapter *_bridgeAdapter;
std::shared_ptr<const facebook::react::ReactNativeConfig> _reactNativeConfig;
facebook::react::ContextContainer::Shared _contextContainer;
}
@end
#endif
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
RCTAppSetupPrepareApp(application);
RCTBridge *bridge = [[RCTBridge alloc] initWithDelegate:self launchOptions:launchOptions];
[[TSBackgroundFetch sharedInstance] didFinishLaunching];
[application setMinimumBackgroundFetchInterval:UIApplicationBackgroundFetchIntervalMinimum];
#if RCT_NEW_ARCH_ENABLED
_contextContainer = std::make_shared<facebook::react::ContextContainer const>();
_reactNativeConfig = std::make_shared<facebook::react::EmptyReactNativeConfig const>();
_contextContainer->insert("ReactNativeConfig", _reactNativeConfig);
_bridgeAdapter = [[RCTSurfacePresenterBridgeAdapter alloc] initWithBridge:bridge contextContainer:_contextContainer];
bridge.surfacePresenter = _bridgeAdapter.surfacePresenter;
#endif
NSDictionary *initProps = [self prepareInitialProps];
UIView *rootView = RCTAppSetupDefaultRootView(bridge, @"P625", initProps);
if (@available(iOS 13.0, *)) {
rootView.backgroundColor = [UIColor systemBackgroundColor];
} else {
rootView.backgroundColor = [UIColor whiteColor];
}
self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
UIViewController *rootViewController = [UIViewController new];
rootViewController.view = rootView;
self.window.rootViewController = rootViewController;
[self.window makeKeyAndVisible];
return YES;
}
/// This method controls whether the `concurrentRoot`feature of React18 is turned on or off.
///
/// @see: .html
/// @note: This requires to be rendering on Fabric (i.e. on the New Architecture).
/// @return: `true` if the `concurrentRoot` feture is enabled. Otherwise, it returns `false`.
- (BOOL)concurrentRootEnabled
{
// Switch this bool to turn on and off the concurrent root
return true;
}
- (NSDictionary *)prepareInitialProps
{
NSMutableDictionary *initProps = [NSMutableDictionary new];
#ifdef RCT_NEW_ARCH_ENABLED
initProps[kRNConcurrentRoot] = @([self concurrentRootEnabled]);
#endif
return initProps;
}
- (NSURL *)sourceURLForBridge:(RCTBridge *)bridge
{
#if DEBUG
return [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index"];
#else
return [[NSBundle mainBundle] URLForResource:@"main" withExtension:@"jsbundle"];
#endif
}
#if RCT_NEW_ARCH_ENABLED
#pragma mark - RCTCxxBridgeDelegate
- (std::unique_ptr<facebook::react::JSExecutorFactory>)jsExecutorFactoryForBridge:(RCTBridge *)bridge
{
_turboModuleManager = [[RCTTurboModuleManager alloc] initWithBridge:bridge
delegate:self
jsInvoker:bridge.jsCallInvoker];
return RCTAppSetupDefaultJsExecutorFactory(bridge, _turboModuleManager);
}
#pragma mark RCTTurboModuleManagerDelegate
- (Class)getModuleClassFromName:(const char *)name
{
return RCTCoreModulesClassProvider(name);
}
- (std::shared_ptr<facebook::react::TurboModule>)getTurboModule:(const std::string &)name
jsInvoker:(std::shared_ptr<facebook::react::CallInvoker>)jsInvoker
{
return nullptr;
}
- (std::shared_ptr<facebook::react::TurboModule>)getTurboModule:(const std::string &)name
initParams:
(const facebook::react::ObjCTurboModule::InitParams &)params
{
return nullptr;
}
- (id<RCTTurboModule>)getModuleInstanceFromClass:(Class)moduleClass
{
return RCTAppSetupDefaultModuleFromClass(moduleClass);
}
#endif
@end
What I Have Tried:
- Manually triggering the event from Xcode → Works (Debug > Simulate Background Fetch).
- Running on a real device → Background fetch does not trigger automatically after 15 minutes.
- Running in an iOS simulator → Background fetch does not trigger automatically; requires manual triggering.
- Checked Background Modes in Xcode - Enabled Background fetch and Background processing.
- Ensured TSBackgroundFetch is initialized - Added [[TSBackgroundFetch sharedInstance] didFinishLaunching] in AppDelegate.mm.
- Set background fetch interval - Used UIApplicationBackgroundFetchIntervalMinimum
Environment:
React Native version: 0.69.4
react-native-background-fetch version: 4.2.5
iOS version: 18.3.2
Xcode version: 16.2
How can I ensure that background fetch is correctly registered and automatically triggered both on a real iOS device and in the simulator? Any insights on resolving this error?