PushNotificationIOS.requestPermissions won't resolve if no event listeners are attached

[frantic]

Description

RCTPushNotificationManager uses startObserving to register for RCTRegisterUserNotificationSettings. According to the docs, the startObserving method won't be called until somebody subscribes to NotificationManagerIOS.

This means there is a scenario when the developer can call requestPermissions without subscribing to notifications first, but since RCTPushNotificationManager relies on NSNotificationCenter subscribtion, the result will never be returned.

This should be fairly straightforward to solve for somebody new to React Native. Feel free to send a PR!

Reproduction

Have this in your JS file

PushNotificationIOS.requestPermissions().then(console.log);

You'll see iOS permissions dialog, however pressing "Allow" won't resolve the promise and nothing will be printed to the console.

Solution

Change the code to this, then uninstall and run the app again (needed to reset iOS permissions cache):

PushNotificationIOS.addEventListener('localNotification', () => {});
PushNotificationIOS.requestPermissions().then(console.log);

Now "Allow" button will work as expected, the promise will be resolved and you'll see log entry.

Additional Information

• React Native version: 0.42.0
• Platform: iOS
• Operating System: macOS

[binoy14]

@frantic If you are okay with it. I would like to take a stab at this.

[frantic]

@binoy14 sure!

[binoy14]

@frantic Can you point me in the right direction? I am not sure which file to edit and what exactly to do.

[frantic]

@binoy14 how familiar are you with React Native? I'd recommend starting with building a simple app that uses local notifications. Then you can try reproduce this bug locally on your computer. Once you have the repro case, check out PushNotificationsIOS native module (Objective-C) and see if you can move some event subscriptions out of startObserving and into methods that actually depend on them.

[cpojer]

This issue has been moved to react-native-push-notification/ios#3.