问题
This is interesting. I have a Universal app. The iPhone and iPad versions both share the same Classes, and just have different xib files. I have been getting frequent reports that after updating the iPad version, it will not run, and simply crashes. However, updates to the iPhone version work just fine. Deleting the iPad app, restarting, and reinstalling will fix the crash at startup issue.
Update With Affected Code:
Ok, so after resymbolicating and viewing the affected line of codes, here is all the areas I feel are causing issues.
I wanted the app to ask a question the first time, and ONLY the first time the app was ran, so in the AppDelegate didFinishLaunchingWithOptions I have:
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
if (! [defaults boolForKey:@"notFirstRun"]) {
UIAlertView *firstrun = [[UIAlertView alloc] initWithTitle:@"Sermon Preference" message:@"Do you prefer audio only, or video sermons? (This setting can be changed at any time in the Settings Page.)" delegate:self cancelButtonTitle:nil otherButtonTitles:@"Audio", @"Video", nil];
[firstrun show];
[firstrun release];
[defaults setBool:YES forKey:@"notFirstRun"];
}
Then I have in the AppDelegate Still:
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {
if (buttonIndex == 0) {
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *nope = @"Audio";
[defaults setObject:nope forKey:@"videosermons"];
[defaults synchronize];
}
if (buttonIndex == 1) {
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *yup = @"Video";
[defaults setObject:yup forKey:@"videosermons"];
[defaults synchronize]; }
}
I wanted these values to be changed in a Settings window, so in the Settings class I have:
- (void)viewDidLoad
{
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *currently = [defaults objectForKey:@"videosermons"];
if ([currently isEqualToString:@"Audio"]) {
segment.selectedSegmentIndex = 0;
}
if ([currently isEqualToString:@"Video"]) {
segment.selectedSegmentIndex = 1;
}
NSString *firstName = [defaults objectForKey:@"firstName"];
if (firstName == nil) {
}
else {
myTextField.text = firstName;
}
NSURL *url = [NSURL URLWithString:@"http://www.bellavenue.org/worship.html"];
self.content = [NSString stringWithContentsOfURL:url];
[super viewDidLoad];
}
The line that the crash log says is causing the crash is:
if ([currently isEqualToString:@"Audio"]) {
What all is going on that is causing a crash ONLY on the iPad, and ONLY when updating an already installed previous version, and not a NEW install?
UPDATE CRASH LOG:
Incident Identifier: EE5B1A62-12DB-4ED5-95CD-0C68CE1614BA
CrashReporter Key: 92fbea1d35e30ff292ba7362f93548dceedefe66
Hardware Model: iPad2,5
Process: Bell Avenue [1013]
Path: /var/mobile/Applications/CE1AE921-5767-4B3C-B223-2C098041C73E/Bell Avenue.app/Bell Avenue
Identifier: Bell Avenue
Version: ??? (???)
Code Type: ARM (Native)
Parent Process: launchd [1]
Date/Time: 2012-12-01 14:11:10.653 -0600
OS Version: iOS 6.1 (10B5105c)
Report Version: 104
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Crashed Thread: 0
Last Exception Backtrace:
0 CoreFoundation 0x3411529e 0x34053000 + 795294
1 libobjc.A.dylib 0x33f3297a 0x33f2a000 + 35194
2 CoreFoundation 0x34118e02 0x34053000 + 810498
3 CoreFoundation 0x3411752c 0x34053000 + 804140
4 CoreFoundation 0x3406ef64 0x34053000 + 114532
5 Bell Avenue 0x0008652e -[Settings viewDidLoad] (Settings.m:64)
6 UIKit 0x3396578c 0x337c5000 + 1705868
7 UIKit 0x3396d5fa 0x337c5000 + 1738234
8 UIKit 0x3399786a 0x337c5000 + 1910890
9 UIKit 0x33820ae4 0x337c5000 + 375524
10 UIKit 0x337c8f7c 0x337c5000 + 16252
11 UIKit 0x337c8a10 0x337c5000 + 14864
12 UIKit 0x337c845e 0x337c5000 + 13406
13 GraphicsServices 0x3afaf59e 0x3afa9000 + 26014
14 GraphicsServices 0x3afaf1ce 0x3afa9000 + 25038
15 CoreFoundation 0x340ea16e 0x34053000 + 618862
16 CoreFoundation 0x340ea112 0x34053000 + 618770
17 CoreFoundation 0x340e8f94 0x34053000 + 614292
18 CoreFoundation 0x3405beb8 0x34053000 + 36536
19 CoreFoundation 0x3405bd44 0x34053000 + 36164
20 UIKit 0x3381f7c8 0x337c5000 + 370632
21 UIKit 0x3381c644 0x337c5000 + 357956
22 Bell Avenue 0x000832fe main (main.m:13)
23 libdyld.dylib 0x39d7ab1c 0x39d79000 + 6940
Thread 0 name: Dispatch queue: com.apple.main-thread
Thread 0 Crashed:
0 libsystem_kernel.dylib 0x385b6350 0x385a5000 + 70480
1 libsystem_c.dylib 0x3a64d11e 0x3a61e000 + 192798
2 libsystem_c.dylib 0x3a68996e 0x3a61e000 + 440686
3 libc++abi.dylib 0x33e1cd4a 0x33e19000 + 15690
4 libc++abi.dylib 0x33e19ff4 0x33e19000 + 4084
5 libobjc.A.dylib 0x33f32a74 0x33f2a000 + 35444
6 libc++abi.dylib 0x33e1a078 0x33e19000 + 4216
7 libc++abi.dylib 0x33e1a110 0x33e19000 + 4368
8 libc++abi.dylib 0x33e1b594 0x33e19000 + 9620
9 libobjc.A.dylib 0x33f329cc 0x33f2a000 + 35276
10 CoreFoundation 0x3405bf1c 0x34053000 + 36636
11 CoreFoundation 0x3405bd44 0x34053000 + 36164
12 UIKit 0x3381f7c8 0x337c5000 + 370632
13 UIKit 0x3381c644 0x337c5000 + 357956
14 Bell Avenue 0x000832fe main (main.m:13)
15 libdyld.dylib 0x39d7ab1c 0x39d79000 + 6940
Thread 1:
0 libsystem_kernel.dylib 0x385b6d98 0x385a5000 + 73112
1 libsystem_c.dylib 0x3a624cf6 0x3a61e000 + 27894
2 libsystem_c.dylib 0x3a624a12 0x3a61e000 + 27154
3 libsystem_c.dylib 0x3a6248a0 0x3a61e000 + 26784
Thread 2 name: Dispatch queue: com.apple.libdispatch-manager
Thread 2:
0 libsystem_kernel.dylib 0x385a6648 0x385a5000 + 5704
1 libdispatch.dylib 0x3aee2974 0x3aeda000 + 35188
2 libdispatch.dylib 0x3aee2654 0x3aeda000 + 34388
Thread 3:
0 libsystem_kernel.dylib 0x385b6d98 0x385a5000 + 73112
1 libsystem_c.dylib 0x3a624cf6 0x3a61e000 + 27894
2 libsystem_c.dylib 0x3a624a12 0x3a61e000 + 27154
3 libsystem_c.dylib 0x3a6248a0 0x3a61e000 + 26784
Thread 4 name: WebThread
Thread 4:
0 libsystem_kernel.dylib 0x385b60fc 0x385a5000 + 69884
1 libsystem_c.dylib 0x3a61f124 0x3a61e000 + 4388
2 WebCore 0x38db41c0 0x38da8000 + 49600
3 WebCore 0x38db40f2 0x38da8000 + 49394
4 CoreFoundation 0x340ea6ca 0x34053000 + 620234
5 CoreFoundation 0x340e89bc 0x34053000 + 612796
6 CoreFoundation 0x340e8de8 0x34053000 + 613864
7 CoreFoundation 0x3405beb8 0x34053000 + 36536
8 CoreFoundation 0x3405bd44 0x34053000 + 36164
9 WebCore 0x38db22a8 0x38da8000 + 41640
10 libsystem_c.dylib 0x3a62f30e 0x3a61e000 + 70414
11 libsystem_c.dylib 0x3a62f1d4 0x3a61e000 + 70100
回答1:
The system caused the app to abort (SIGABRT). There are several issues in the code:
- All code in
viewDidLoadshould be actually executed inviewWillAppear:. None of the code is relevant to be executed when the view is loaded by iOS. self.content = [NSString stringWithContentsOfURL:url]is a synchronous call, blocking the main thread for how ever long this takes. You should either call this asynchronously or use an NSOperationQueue to load the content and then set it on the main thread again. Right now this blocks the loading process of the view controller, which is an ever worse idea to do.- The exception message is not shown, but I suspect you the
currentlyobject is not of typeNSStringand it gets anunrecognized selector sent to instanceerror.
You may want to read this series about how to read and work with crash reports: http://www.raywenderlich.com/10209/my-app-crashed-now-what-part-1
来源：https://stackoverflow.com/questions/13661966/updated-app-crashing-on-ipad