I have an iPhone application which uses a CollapsableTableView. After upgrading to iOS 6 I get a crash in the application with the following error.
"A view can only be associated with at most one view controller at a time! View is associated with CollapsableTableViewHeaderViewController: 0x8a93430. Clear this association before associating this view with CollapsableTableViewHeaderViewController: 0x8a943c0"
It would be rather helpful if I anyone of you has come across the same problem in order to find a solution for it. Thanks in advance.
You must be using something like this:
[self.addSubView collapsableViewController.view];
This kind of association is not allowed, since one view can't be associated with two view controllers as stated in the error description.
Related
Recently I have been working on an old swift project built in back in 2015. Its really difficult to find which ViewController is executing currently because of the naming convention, usage of really massive storyboard(I feel terrified to even go to the main.storyboard) and various reason like usage of different language. Of course I can find it but it takes long. I was thinking if there is any way like when I run the project on a device and navigate to different page is there any way to see in the console which ViewController is executing ?
There is a quick way to find what view controller you are on when you are running your app.
1) Launch your app on the device or simulator.
2) Go into Xcode and tap this button:
3) This will open the Debug View Hierarchy. Click on the phone and you will see all the elements in the top bar. You can also see a hierarchy on the left-hand side. In here, you can click down and you will see the name of the view controller on screen.
Using the debugger after putting a breakpoint where you prefer you can write this and press return.
Swift 4.x
po UIApplication.shared.keyWindow?.rootViewController?.value(forKey: "_printHierarchy")
This method is a private API, thus you cannot use on production code, just use it in debug or from the debugger console.
I think it is better to see in debug area for your current viewcontroller named self, you get all information from there open the dropdown and and see you need to put break point in your viewController init method or where you want to debug, However you want to know programatically which is you current viewController you can get it by
appDelegate.window.currentViewController()
If you need which ViewController is Pushed or presented you can get from the above code but the case will be different if you are using the Slidemenu controller, I mean it is totally depends on how you have started navigation and which navigation controller is currently is use.
Can you briefly describe why you need current ViewController so i can help you further.
I've run into a little problem while developing a Core Data driven Quiz and be a bit confused about a best practice to solve my problem.
I have approximately five templates for the different questions, which will be loaded in case which question is displayed. So I check which template has question 1 and push the new question-template view into my navigation controller. Because its always the same code I want to write a function (I came from php) which gets the next question-id as argument and decide which template will be loaded and push the next view into the navigation-controller.
What is the best practice to solve this problem? Can I write a function with access to the navigation-controller, and my Core Data classes. And if yes where I have to create this function?
Okay I think I found an way but gets here another Error. I create a class called QuestionRouter and define an class method. I'll import this class into each viewController where it needed. The class method gets the correct template from Core Data without an problem. But now I wan't to load the correct view. For that I need to access the navigationController defined in my AppDelegate.
So how I can access the navigationController in my AppDelegate for another class?
Hope for an answer.
Mister-D
I have a few views in my database that im using in my ASP MVC-application. Now I am experiencing a very strange problem. There are 8 views in the database but even if I check them all in the Create Enity Data Model-guide only 7 of them are available as objects in the datacontext.
If I try to import ONLY the view that gets left out I get an empty model.
Is there some kind of limitation that I dont know of? Or is this a known problem?
Sounds like there is something special with this view. Things to check:
Are the rights the same on this view as others?
Try running a select on this view from query manager to confirm that it works
Open up the "empty" model in an xml view and see if there are any error messages in it
I have ran into issues importing tables and views with no key defined. The entity framework will try to assign one automatically if it can, but if you have duplicate data you may have to create a primary key before EF will bring it in.
That didnt do the trick. I removed all joins from the view definition and added a very simple view (basically just a select from a single table). That worked. Then I added the joins one by one and made the view more complicated for each step. Now I have the same view as I had before I started this process and I can now import it without problems. Something is strange in the state of Denmark
I am close to finishing my first application (a UITableView style one) on the iphone but have realised it will look much better, and stand a far better chance of getting through the approval process, if it is presented as a navigation-based app rather than a view-based one - in hindsight my initial choice is not really suitable...
Is it possible for me to somehow change easily the application into a new type, or would i be better starting again from scratch with all the hassle that would entail...
thanks for any advice on how it may be done,
karl
It wouldn't be particularly difficult to shift the means of interaction to a navigation controller from a simple view controller (it also isn't difficult to go the reverse direction). Although, there isn't anything as simple as a tutorial on how to do it or menu item you can select. You could look at the plumbing generated by Apple's template for a navigation based application and add the necessary glue to your app delegate. Once that is in place you could simply push your view based applications view controller onto the navigation stack. If you have more specific questions or are stuck somewhere in particular we can help to get you un-stuck if you provide details about where you are running into issues.
As an aside, I doubt your application will be rejected solely for being view based vs. navigation based.
Hmmmmm, for soem reason t wont let me add anything to comment on your post!
Anyway, i guess this is as good as anything here...
Ive been messing for the last hour or so and have managed to integrate my old code/data etc into a new navigation one without too many problems, in fact it looks nicer with a title bar at the top!
(I do like to try and work stuff out for myself so its a good learning curve!)
I am still struggling in that although the new view opens up i am
struggling to use a string from the first view (I have a UITableview table in there, i select a row and get a correct value from it which i currently check via an alert message) in the second view.
for some reason i do not get a title bar and 'back' button in the 2nd view so i guess it is not being put on the stack correctly (I have put a quick 'return' button in the view for testing purposes so i can navigate backwards and forwards).
Still, Im about 100% further on than i was earlier!
cheers for the reply,
Karl
I'm working on an iPhone app (first real programming project) and I had two views that would go into tabs in separate applications to build them, where they work fine. Then I added them back into the main project; The tableviews bring on a crash with an numberOfRowsInSection] unrecognized selector sent to instance 0xXXXXXX so I isolated the other view to fix any errors there first. I'm using xibs.
But on the other view, when I click a Button that triggers a custom method, I get an *** -[UIViewController methodName]: unrecognized selector sent to instance 0x####XX0 just like the last one.
What also puzzles me is that the console won't print anything else except these errors; I have NSLogs() all over the place and they're not showing up, even in the appDelegate. They do however show up when they're in the main. (Because of the application life-cycle right?: then the error gets there first and I don't see my NSLogs)
The unrecognized selector messages are logged because of methods. I have all my synthesize statements and have searched questions here, but they're not like mine (I think.)
When you say you added the XIB files "back into the main project" it makes me think this is the likely area of concern.
I think it may be the case that these XIB files are still thinking they are classes in the old application (where you originally built them). I suggest:
Opening up each XIB file and removing all the connections
Then check the class name of the "file's owner" and check that this is the class in your new application. If the class names are the same in the old app as the new, change to something else and then back again.
Hopefully this will sort it. If it doesn't, try creating a brand new XIB file and then building it in the same way as you built the others. If this still doesn't work the problem is in the class; if you let us know then we can come back with further ideas in this area.
Hope that helps!
I've since removed the second view from it's xib and instead put it in the main xib, with an added UIViewController object that has it's class set to my subclass. Now it's working, and I'm moving on to the next part. I think it was that I left out UIViewController in one way or another from the xibs
As stated above, almost everything being worked out now. Thanks though and silly me for posting such a question.