Cocoa - Loaded nib file disappears when focus is lost - objective-c

I have a nib file I've loaded like so [NSBundle loadNibNamed: #"myNibFile" owner: self ] and it pops up fine, but when it loses focus, it simply disappears. I've checked to see if it's vanishing behind my main window but it's not. My app is pretty big so I'm not sure what could be causing it. I have garbage collection enabled if that makes any difference. Does anyone know of any problems with loaded nib files and losing focus that I should look into? If necessary I can start posting some samples from my code.

Hmmm... I just deleted the nib I was loading and recreated it and it started working. Strange... Seems fixed now though.

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subclass of UIViewController is unable to call loadView method

i have a subclass of UIViewController, and when it is called from another class the app just freezes - i used the Xcode debugger and figured that when I'm trying to access the class's view property the app freeze. another weird thing is that when i type in the debugger control panel: "po objectOfTheProblematicClass.view" the debugger stops responding.
the code I used was similar to this:
UIStoryboard *sb = [UIStoryboard storyboardWithName:#"Main" bundle:[NSBundle mainBundle]];
WTStickyViewController *stickyVC = [sb instantiateViewControllerWithIdentifier:#"WTStickyViewController"];
stickyVC.sticky = sticky;
// Setup view controller containment:
[self.parentViewController addChildViewController:stickyVC];
self.containerView = self.parentViewController.view;
[self.containerView addSubview:stickyVC.view];
WTStickyViewController is the subclass of UIViewController. the app freezes when it reaches
[self.containerView addSubview:stickyVC.view];
but it's because this is the first time that stickyVC.view is called.
if for example i would put somewhere in the code
UIView *viewForExample = stickyVC.view;
the app would freeze there.
the exact same app works fine when compiled on a device with iOS 8 but has this problem with iOS 9.
if anyone knows why is this happening and if there is a solution it will be great. thank you.
I was having a similar issue and it was absolutely maddening. The CPU went to around 100% in the resource monitor during debug as the app deadlocked. Printing to console or just generally accessing the view controller's view property caused this behavior. Ultimately, what 'fixed' it for me was removing it from the base localization file. I know that doesn't make sense, but I'll elaborate as best as I can.
I'm maintaining a legacy universal app that has 2 'main' storyboards called Main_iPhone and Main_iPad, which as you can probably guess are the loaded dynamically based on what device you're launching on. I noticed that only the iPhone nib view was deadlocking as described, and iPad was loading fine. The only thing I could tell as that the iPhone storyboard had localization enabled while the iPad storyboard had not. So here's the steps I took loosely to remove it from base localization (you may want to do this in a separate branch/sandbox to make sure this works before deleting project references):
Right click the problematic view and/or storyboard in question, show in finder. For me it was inside the Base.lproj folder as expected.
[Re]move the file to a different directory so Xcode can not find the link the project (file goes red in file browser). Press delete to remove the file from the project file's reference from the project itself.
Add the file back at the new location in your repository/project structure so Xcode picks it up as a new file. Ensure all of your references to the file are updated to the new location.
Verify your storyboard/xib file is not localized anymore, clean project, re-run and see if the issue is still there (see image).
You can also just update the file location using the update location button in the file properties view on the right side (see other image).
Don't know if this will fix it, but I thought I'd share what helped me in the chance that it helps others as well.
A bug report was sent to apple and hopefully it will be fixed soon - the problem is indeed with Xcode 7.
If you are encountering a similar problem, it can be solved by doing one of the following:
1) Use Xcode 6.4, at least until apple fixes this bug.
2) Rebuild the problematic view in the storyboard.
I will post the radar link once I got a chance to speak with my manager about it...

Error loading .xib - application crash

I am banging my head against a brick wall. I am trying to push a view onto a UINavigationController in the usual manner:
[[self navigationController]pushViewController:vc animated:YES];
When I do this the app crashes with the following error:
__CFStringEncodeByteStream + 17
Thread 1: EXC_BAD_ACCESS (code=2,address=xxxxx)
Now, I have replaced the ViewController in question with a template provided by XCode and I do not get the error so the issue must be with my UIViewController class. Furthermore, if I replace the nib name with that of the template UIViewController class it works .i.e.
MyViewController *myVc = [[MyViewController alloc]initWithNibName:#"XCodeViewController" bundle:nil];
This leads me to think that the issue is actually with the nib and not the class itself. I have checked through all the connections and there are no errors or warnings.
Hopefully somebody can help.
Thanks
I was dealing with a very frustrating bug similar to yours, and everything was in place.
The newly created xib was added to the Bundle resources, no nil pointers or released pointer, NSZombieEnabled was set. The File's Owner was set to the correct ViewController as well
After sitting down with my senior for 30 minutes, we finally realized what was wrong -
In the newly created Xib, even after you assign the File's Owner to the ViewController there is an additional step which you need to take.
You need to have the main View's referencing Outlet set to the File's owner as well. The easiest way to do this is to Drag the "+" sign on the referencing outlet(From the Connections inspector) to the "File's Owner" in the Document Outline. After this you just need to click on "view" which pops up and you should be good.
Hope that helps you or anyone else facing the same problem
Need more info to answer, I can give few possibilities.
Check if the class name is mapped properly in your identity inspector.
And check your connections too. If your view is mapped in xib., etc.
If your running the app in OS below 6.0 & built with features such as Auto layout, it leads to crash.
There are multiple possibilities.
Hope this gives an insight.
Check if your nib is added to the application bundle. You can do that by selection you project file->Build Phases->Copy Bundle Resources.
If it is not there, add it.
I had the same issue yesterday and this was the problem.
I hope it helps.

how to remove image stuck in my nib after all references removed

My iPad app will periodically crash with a memory warning, and it shows "Could not load the "myimage.png" image referenced from a nib in bundle..."
I have removed this from my .h and the nib and it, obviously is not in my bundle. I cannot get rid of this reference. I have checked everything there is no pointer to it in my nib or in my code, how can I view my nib such that I can get rid of this bad reference??
Anyone else experience this?
Never seen that happen but you could just open the .xib file in a text/xml editor and do a search for myimage.png. CHeck that out and infer the problem from what you find :) Post what you find if you cannot get a solution from that.

iOS 3 - UITabBarItems disappear from UITabBar after a memory warning occurs

At a great number of requests from people using older iOS hardware, I'm currently refactoring and optimizing my app so it will work on iOS 3. That being said I've got a glitch with my UITabBar that I can replicate on all of the iPhone 3G units I've tested it on.
The glitch appears to have been fixed in iOS 4, but I was wondering if before that time, anyone else had this glitch as well and had figured out a (relatively elegant) workaround for it.
The problem is what you can see below; when a memory warning occurs and all of the views offscreen are released, when I bring a view controller with a tab bar back on screen, all of the UITabBarItems that are supposed to be in it are gone. As far as I can see, they're not being drawn at all; ie tapping the tab bar has no effect. After setting breakpoints and examining the UITabBar and its items in memory, they're all still there (ie not getting released), just that they're not getting redrawn when the UITabBar is re-created in the controller loadView method.
My app works similar to the official Twitter app in that I implemented my own version of UITabBarController so I could control the integration of it with a parent UINavigationController properly. I set it up as closely as possible to the original UITabBarController class though, with all of the child view controllers handling their own respective UITabBarItems and initializing them inside the class' init methods. Once the child view controllers are passed to my TabController object via an accessor method, the tabBarItems are accessed and added to the UITabBar view.
Has anyone seen this behaviour before and know of a way I can fix it? I'm hoping there's a really simple fix for this since it already works in iOS 4, so I don't want to hack it up too badly.
Thanks a lot!
After a bit of research, I think I found a solution to this. It's not the most elegant solution I was after, but it definitely works.
I'm guessing after a memory warning is triggered, something is happening to the UITabBarItem objects that basically renders them corrupt. I tried a lot of things (flushing out the UITabBar, re-creating the controllers array etc), but nothing worked.
I finally discovered that if you completely destroy the UITabBarItems and allocate new ones in their place, then those ones will work. :)
So my final solution to this was to add an extra condition in the viewDidLoad method of my controller that if the detected system was iOS 3, and there was already an array of UITabBarItems, it would go through each one, copy out all of the properties needed, destroy it, allocate a new one and then copy the old properties over to the new one.
I'm still going to keep an eye out for a better solution (I think there's a bit of overhead in this method), but thankfully at this stage, iOS 3 legacy support is becoming less and less of an issue. :)

WebView Cocoa control crashing on window close

I get a crash in WebEditorClient::clearUndoRedoOperations which is trying to access -[WebView(WebViewEditing) undoManager] when I close the main window of an NSDocument that contains a webview with a text editor in it. It only happens when there is an undo-able state. Seems like a bug in Cocoa, but I might be doing something wrong. Any ides why this might be going on? The web view is in a nib and not created programmatically, so I'm not sure what I can do to even begin fixing this.
Well, removing it from superview prior to calling close on the document seems to have fixed it. Still, that doesn't explain what was going on, but just putting it here in case other people have this problem.