Question

The application that developing is running fine on Xcode simulator, but when I am testing it on real device is terminated. Below is what my phone’s console prints out when app is terminated.

Nov 22 00:51:09 iPhone ReportCrash[3862] <Notice>: Formulating crash report for process CoL[3860]
��Nov 22 00:51:09 iPhone ReportCrash[3862] <Error>: libMobileGestalt copySystemVersionDictionaryValue: Could not lookup ReleaseType from system version dictionary
��Nov 22 00:51:09 iPhone com.apple.launchd[1] (UIKitApplication:pan.ConquestOfLancaster[0xd857][3860]) <Warning>: (UIKitApplication:pan.ConquestOfLancaster[0xd857]) Job appears to have crashed: Segmentation fault: 11
��Nov 22 00:51:09 iPhone backboardd[52] <Warning>: Application 'UIKitApplication:pan.ConquestOfLancaster[0xd857]' exited abnormally with signal 11: Segmentation fault: 11
��Nov 22 00:51:09 iPhone ReportCrash[3862] <Notice>: Saved crashreport to /var/mobile/Library/Logs/CrashReporter/CoL_2012-11-22-005109_iPhone.plist using uid: 0 gid: 0, synthetic_euid: 501 egid: 0
��Nov 22 00:51:09 iPhone awdd[3863] <Error>: libMobileGestalt copySystemVersionDictionaryValue: Could not lookup ReleaseType from system version dictionary

Basically, the problem occurs when I am firing a NSTimer (countdown) and reach ‘1’. Freeze for a while and then terminated.

Here is the method where timer initialised:

- (void)MapMenu:(MapMenu *)menu didSelectButton:(NSInteger)index{

    if (index == 0) {
        if (self.owner == nil && distance < 10) {
            CountDownTimer* countDown = [[CountDownTimer alloc]init];
            [countDown startTimerOn:parentView];
            [self performSelector:@selector(attackTo:attacker:) withObject:nil afterDelay:20.0];
        }
        else if (self.owner == @"Player_1")
            NSLog(@"You have already occupy this building with name, %@", self.title);
    }
}

- (void) attackTo: (BuildingViewController*) selectedBuilding attacker: (NSString*) attacker{

    self.owner = @"Player_1";
    NSLog(@"Building has a new owner with name, %@", self.owner);
}

Does anyone has a clue for this. Really … lost!

Thanks in advance

Answer 1

I am not sure if this is the source of the crash, but you do have a problem right here:

[self performSelector:@selector(attackTo:attacker:) withObject:nil afterDelay:20.0];

Basically, the fact that selector call has two : means that it is expecting two arguments. If you use the method performSelector:withObject:afterDelay:, you can only use it with a method that has one argument.

For example,

[self performSelector:@selector(doSomething:) withObject:object afterDelay:20.0f]

is equivalent to

[self doSomething:object]

and it will be performed after about 20 seconds.

In this case, you have a mismatch because your @selector takes two arguments, so you can not use it with that particular performSelector method.

While there is a performSelector:withObject:withObject method that takes two arguments, it does not have a delay argument. You might need to use NSInvocation instead, or change the attackTo:attacker: so that it uses a single argument (for example, an NSDictionary).