Case 1340464 - remove GC allocation every frame on Android #101
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| { | ||
| s_ReceivedNotificationList.AddRange(s_ReceivedNotificationQueue); | ||
| s_ReceivedNotificationQueue.Clear(); | ||
| if (m_ReceivedNotificationQueue.Count == 0) |
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This feels fragile, for this code to work correctly, m_ReceivedNotificationList has to be empty, when the switch occurs. If it's not empty then out of order processing of notifications is possible. Only by looking at the whole file I understand that m_ReceivedNotificationList is empty when this switch occurs, but still if in the future someone will mess with m_ReceivedNotificationList, it will be easy to miss this place
Consider adding a safeguard
if (m_ReceivedNotificationList.Count != 0)
throw new Exception(..)
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If it's not empty, it means there are leftover notifications from last processing which shouldn't happen. Actually, this code still has a bug where this could happen (in case of exception), but that's addressed in different PR. When such leftovers happen, you get callbacks called again for the same notification next frame, most likely leading to the same exception again and postponing the same issue to the next frame etc. This change would scramble the ordering, but you'd still get bombarded with callbacks every frame when this happens.
Throwing exception like you propose would prevent callbacks from being called with logging about a bug. IMO, not throwing exception gives a clearer indication of bug (but it doesn't log the exact issue).
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"clearer indication of bug" - really? :) it's really not that apparent, especially for a green user. Well, if you're a fan of hidden bugs, so be it :)
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It's for sure clearer in our test project, reducing chances of us releasing a bug :)
## [1.4.3] - 2022-04-15 ### Fixes: - [Android] [issue 101](Unity-Technologies/com.unity.mobile.notifications#101) Fix GC allocation every frame. - [1360115](https://issuetracker.unity3d.com/issues/mobile-notifications-project-settings-window-loses-focus-when-clicking-on-any-category-while-mobile-notifications-pane-is-open) Fixed focus loss when trying to switching from notifications settings. - [Android] [case 1376849] Fixed receivers needs to be marked as exported in manifest file, disable exact alarms on Android 12 because they require special permissions. - [iOS] [1375744](https://issuetracker.unity3d.com/issues/ios-app-freezes-slash-crashes-when-both-mobile-notifications-and-firebase-are-used) Fixed application startup hang when application uses Unity notifications or Firebase. - [iOS] [case 1382960] Handle numeric data in UserInfo. - [iOS] Correctly handle boolean values in UserInfo, previously boolean values were detected as numbers and get parsed as 1 or 0, now they will be correctly handled as 'true' and 'false'.
Improve Android implementation to be more performance and not make GC allocation every frame.
Changes:
To QA: try to break it (flood notifications).