I've just finished off an app for the iPhone which, until today, ran fine on the iPhone simulator and actual devices.
I tried changing the xib which is loaded in the applicationDidFinishLaunching method in my application delegate class - all I did was change the string in initWithNibName.
When I launch the app on the simulator, the Default.png image is shown, then the app crashes with an uncaught exception. When running on a device, the Default.png image is shown for about 10 seconds, the UI is never loaded and I get 'GDB: Program received signal: "SIGABRT".' on the Xcode status bar. Debugging shows that applicationDidFinishLaunching is never actually reached before the app crashes.
Setting the starting xib back to the original solves the issue, but now I've made a change and saved it in the Interface Builder and the app shows the same issues as above - I've made no code changes at all.
Is this a memory issue, or a known issue of a common mistake?
NOTE: I've made no code changes whatsoever, and the only changes I've made to the xib are cosmetic, the IBOutlets are all intact.
You probably changed an IBOutlet's name in code without changing it in the xib.
Sorry guys, my fault - it appears I deleted the MainWindow.xib file, so the delegate wasn't called on startup after I made changes. I've recreated it and linked it to the app delegate and UIApplication so now everything works.
You probably had IBOutlets connected from a xib back into your code, and those connections are broken.
You'll have to give us a little more detail on how the nibname string was changed. Did you rename your xib file?
I renamed some classes and Xibs and got SIGABRT into main.m
the Class name in Identity Inspector may be pointing to non existant class name
its because in the initWithNibName you are not giving the correct xib name so it will crash
Related
While updating a UIViewController, all my IBOutlets are suddenly not registering with Interface builder. (note: i did not change any of these outlets in the .m file)
The class in the identity inspector is correct, the IBOutlets are shown as connected in the .m file and the app still runs fine.
However, I cannot add any new ones or edit the current ones. Whats happened here and how do i go about correcting it?
I've come across the solution. It was as simple as closing x-code and opening it again. Not sure why this happened in the first place, might be a bug, but if anyone gets the problem try that first.
I made a universal application that contains NIB files for both ipad and iphone UI's. In my view controllers initWithNibName method I call UIUserInterfaceIdiomPad == UI_USER_INTERFACE_IDIOM() to detect whether the controller is running on iphone or ipad.
I then launch their respective nib files. When I run the app on iphone, it works fine, but when I run it on ipad it eventually crashes with a EXC_BAD_ACCESS error. This error occurs when I use a view controller to launch another view controller, which then launches another one in the navigation stack. This error occurs as soon as I click the view that belongs to the third controller of the stack.
I cannot distinguish a difference between the NIB files that would cause a crash. I have been working tirelessly to figure out why this is happening but I cannot fix this error. Does anyone have any insight into what might be going on?
Any advice on how to approach fixing this problem would be very appreciated.
The first thing you should do is enable the "All Exceptions" break point. This will often accurately tell you the line of code where the EXC_BAD_ACCESS is happening.
Next, I would turn on zombies and see where the over-release is happening. To do so, in Xcode, while holding the option key, click Product | Run.... In the ensuing window, add NSZombieEnabled to the environment variables list.
Then run. Do the normal things you do to cause the crash and see where the debugger lands. With any luck, it will stop where the problem is actually occurring.
When you get a EXC_BAD_ACCESS it means you're trying to access/release something that's already been released. If you're in a non-ARC situation, it normally means you've inadvertently released something when you didn't mean to, so just check for alloc/init and release balance. If, however, you're in an ARC situation, I would bet it has to do with not niling a delegate when a view controller gets released.
For example, if you have a MKMapView and have set its delegate to your view controller, you should nil its delegate when your view gets unloaded or dealloc'd. Otherwise, messages will continue to get set to it. Or, another possibility is that you've added your view controller as an NSNotificationCenter observer and didn't remove it as an observer when the view controller was unloaded or dealloc'd.
Another possibility is that you're re-using view controllers between the two versions of your universal app. If you are accessing anything by an identifier that doesn't exist in the nib for the iPad, that would cause a crash--though if you're using nibs as opposed to storyboards, that may not be an issue.
That's about all I can think of for now. Try to zero in on where it's happening and post code here if you still can't figure it out.
Best regards.
First off, I will say i've spent 6 hours on this topic and have read everything the internet has to provide, which is why i came here.
I have converted to Universal, Xcode created the MainWindow-iPad.xib and everything seems fine.
Here are my questions:
1) What are the naming conventions for new iPad-specific xibs? Xcode created "-iPad" but i believe im supposed to be making them "~ipad". Why the difference?
2) (MOST IMPORTANT) After creating several "~ipad" xibs, Xcode seems to know to load these. So I'll copy the content in say, "RootViewController.xib"
and paste it in "RootViewController~ipad.xib". THIS IS THE PROBLEM: this new ~ipad xib has no outlets or referencing outlets!
I can't link the buttons on my page to anything. How do i do this without having a separate ~ipad .m and .h for everything?
Thank you guys for your help! I'm going to write a tutorial on this once I get this all working.
Just set the class of that ~iPad nib to be the same classname as the cooresponding iPhone nib. This is done in the inspector in Interface Builder. You may have to connect the outlets back up depending on the order you do things. I would think that if you copy the objects from the iPhone nib to the iPad nib AFTER you set the class, then the outlets would stay wired up.
I have a view that I created using default buttons and background in Interface Builder. The app runs properly. I added .png background images to the view and to the buttons. Build the app and run it and the updates do not show.
I've also tried something simple like changing the text of the button or add another button and the changes are not propagating.
I've cleaned targets, manually deleted builds in Finder, and have shutdown the computer. What else am I missing?
I had the same experience. It turned out that I'd renamed my class and my xib file, but in another class I was creating the view with:
MyNewViewController *myNewViewController = [[MyNewViewController alloc]
initWithNibName:#"MyOLDViewController" bundle:nil];
An oversight, but the surprising part to me is that when this Nib file didn't exist in my project, it managed to build successfully using a (presumably cached?) old Nib file... and the application happily ran, though showing an out of date interface.
Correcting what was passed to initWithNibName immediately corrected the issue for me.
This might sounds easy - but are you sure you linked up the view to the view controller in Interface Builder? I've done it before where I just forget to link them
I also had the same experience. For me the fix was to reset all content on the simulator.
So I have an app which runs fine on the simulator, but not on the actual device.
At runtime, it gives me the following error:
2010-12-05 19:58:32.006 Sports[4668:307] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UITableView isEqualToString:]: unrecognized selector sent to instance 0x800800'
A bit about the structure: I have a Tab Bar Controller, the first view being a UINavigationController.
The view in there is a UITableView. One thing that may or may not be related is that if I do #synthesize tableView; in the table view controller, the table stays blank on both simulator and phone (but does not crash).
If I take that out, it loads the correct data on the simulator, and crashes on the phone.
Where should delegate/dataSource be linked to in the Interface Builder? I tried linking it to "View" to "File's Owner", and making a new "ViewController" and none of those worked.
Both the delegate and dataSource should be linked to File's Owner, which is the view controller class that declares the table view as an IBOutlet; this should be the same view controller that owns the nib file. Additionally, that view controller should be implement the UITableViewDelegate and UITableViewDataSource protocols.
Add that #synthesize line back in, (unless you're subclassing UITableViewController, as pointed out by grahamparks in the comments!) make sure those connections are right, and, finally, make sure you've declared an IBOutlet for the table view, and connected that properly between your class and interface builder.
Found it!
Turns out that there wasn't really a problem with this at all. The problem was that the date field in my database, when run on my phone was always zero/nil.
Why? Because the NSDate object created never initialized and stayed at nil.
Why?
Because my phone is in 24 hour time and did not parse the am and pm properly.
Lessons learned!
Run your app with NSZombieEnabled set to yes. See http://www.cocoadev.com/index.pl?NSZombieEnabled for an explanation about it and how to set it. I think what you will find is that the app will now throw an exception in the simulator telling you that you are sending a message to an object that has been released.
Based on the error message you are receiving, I expect the culprit is a NSString or NSMutableString object. If it is an NSString then warning, that NSString could be shared by several different objects so figuring out where the extra release is might be hard.
Never fear though, Instruments helps tremendously in this regard. Here is a link that explains how to use Instruments to find out exactly where your object is being retained and released so you can track down which release is inappropriate. http://www.markj.net/iphone-memory-debug-nszombie/
Good luck!