iOS applicationDidBecomeActive: not called after didfinishlaunchingwithoptions: called

Question

It is wired that logs for these two method are not always pairing.

# AppDelegate.m
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    NSLog(@"didFinishLaunchingWithOptions");
}

- (void)applicationDidBecomeActive:(UIApplication *)application {
    NSLog(@"applicationDidBecomeActive");
}

Answer 1

If your app is working with background fetch enable, iOS will launch your app as background fetch mode and prepare for data, un-periodically.

Launch due to a background fetch event, didFinishLaunchingWithOptions will called but applicationDidBecomeActive will not get called.

You can duplicate this scenario by turning on option "Launch due to a background fetch event" by edit run scheme in Xcode.

Answer 2

- (void)applicationDidBecomeActive:(UIApplication *)application

Is only called when your app is moved from inactive to active state or transitioned to foreground.

So not weird or wrong, everything is as it should be.