App running on iOS 5, iOS 6, but crashing on iOS 7 - ios

Question

We have submitted the app on the app store, and it was approved.
But after a day we found out that it is running fine on iOS 5 and 6, but it is crashing on iOS7.
Following is the crash log.
Nov 14 01:45:16 Mys-iPhone AchMyieveCard[4871] <Warning>: Successfully received the test notification!
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Remove User
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Hide the Progress Bar1
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Hide waiting view
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Hide the Progress Bar2
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: view did dis appear
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: MainNavController :: setMyToolbar
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Menu Name = My Cards
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: MCPClient :: Method to prepare URL with provided url parameter values
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Key : lastName
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Value : Cunningham
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: key lastName, value Cunningham
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Key : ssn4
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Value : 2123
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: key ssn4, value 2123
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Key : zipCode MyNov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Value : 12345
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: key zipCode, value 12345
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Prepared URL after appending parameters lastName=Cunningham&ssn4=2123&zipCode=12345
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: Hidden --- 0
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: View Controllers = (
"<UINavigationController: 0x16557a40>",
"<UINavigationController: 0x165cd7b0>",
"<UINavigationController: 0x165d6490>",
"<UINavigationController: 0x165d89e0>"
)
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: View will appear
Nov 14 01:45:16 Mys-iPhone MyApp[4871] <Warning>: --- >>>>> hasEnteredInAppFirstTime ::: 1
Nov 14 01:45:16 Mys-iPhone ReportCrash[4877] <Notice>: ReportCrash acting against PID 4871
Nov 14 01:45:16 Mys-iPhone ReportCrash[4877] <Notice>: Formulating crash report for process MyApp[4871]
Nov 14 01:45:16 Mys-iPhone com.apple.launchd[1] (UIKitApplication:com.i2cinc.MyApp[0xbb1c][4871]) <Warning>: (UIKitApplication:com.i2cinc.MyApp[0xbb1c]) Job appears to have crashed: Segmentation fault: 11
Nov 14 01:45:16 Mys-iPhone backboardd[28] <Warning>: Application 'UIKitApplication:com.i2cinc.MyApp[0xbb1c]' exited abnormally with signal 11: Segmentation fault: 11
Nov 14 01:45:16 Mys-iPhone ReportCrash[4877] <Notice>: Saved crashreport to /var/mobile/Library/Logs/CrashReporter/MyApp_2013-11-14-014516_Mys-iPhone.plist using uid: 0 gid: 0, synthetic_euid: 501 egid: 0
Nov 14 01:45:25 Mys-iPhone mstreamd[4878] <Notice>: (Note ) mstreamd: mstreamd starting up.
Nov 14 01:45:25 Mys-iPhone mstreamd[4878] <Notice>: (Note ) PS: Media stream daemon starting...
Nov 14 01:45:26 Mys-iPhone awdd[4879] <Error>: CoreLocation: CLClient is deprecated. Will be obsolete soon.
Nov 14 01:45:36 Mys-iPhone routined[34] <Notice>: CoreLocation: </System/Library/LocationBundles/Routine.bundle> woken up by Core Location
Nov 14 01:45:36 Mys-iPhone kernel[0] <Debug>: 154088.182708 wlan.A[27556] AppleBCMWLANNetManager::updateLinkQualityMetrics(): Report LQM to User Land 100, fAverageRSSI -69
Nov 14 01:45:36 Mys-iPhone backboardd[28] <Warning>: Launch Services: Registering unknown app identifier /System/Library/LocationBundles/Routine.bundle failed
Nov 14 01:45:36 Mys-iPhone backboardd[28] <Warning>: Launch Services: Unable to find app identifier /System/Library/LocationBundles/Routine.bundle
Nov 14 01:45:36 Mys-iPhone SpringBoard[33] <Warning>: Unknown application display identifier /System/Library/LocationBundles/Routine.bundle.
Code
NSLog(#"View will appear");
NSLog(#" --- >>>>> hasEnteredInAppFirstTime ::: %u", [mClient hasEnteredInAppFirstTime]);
if([mClient hasEnteredInAppFirstTime]) {
mClient.hasEnteredInAppFirstTime = NO;
NSLog(#"Default Screen %#", mClient.defaultScreen);
if([mClient defaultScreen] == (id)[NSNull null] || [mClient defaultScreen].length == 0 ) {
NSLog(#"Default screen is nil, going to load dashboard");
[mClient setUPProgressHUDForView:self.view withLable:#"Generating Dashboard" andMessage:#"Please Wait.."];
for(UIView *subview in [self.scrollView subviews]) {
[subview removeFromSuperview];
}
NSLog(#"--> ::: Going to change here");
[self generateDashboard];
} else {
NSLog(#"Going to push default screen : %#", mClient.defaultScreen);
//[mClient setUPProgressHUDForView:self.view withLable:#"Loading Default Screen" andMessage:#"Please Wait.."];
[self pushDefaultScreen:mClient.defaultScreen];
}
}
Kindly help me and let me know what the issue is, why it is crashing and what the solution is.

Answer 1

You are mutating an array as you change it:
for(UIView *subview in [self.scrollView subviews]) {
[subview removeFromSuperview];
}
You should make a copy of the subview array, and send the message to each object in it:
NSArray *oldSubviews = [self.scrollView.subviews copy];
for(UIView *subview in oldSubviews) {
[subview removeFromSuperview];
}

Answer 2

I was accessing
mClient defaultScreen
property of another class. and while setting the value in defaultScreen, i was not using this operator with property name. this was working fine in iOS6, but was causing crash in iOS7.
Previous line of code in mClient:
defaultScreen = #"screen name";
New code:
this.defaultScreen = #"screen name";
now crashed is fixed. :-)