Edit: While my comments have an iOS 5 working example, I am still getting this for other versions. I've now implememted a test to only register and dequeue cells if iOS 5, but it's really puzzling!
still receiving _accessibilityUpdateRemoveControl exceptions, strange nuisance, appears to be something with the edit controls, nothing is retained so nothing needs deallocing, but will try, and post the answer if I find it!
This was working yesterday, and now it's not... I changed nothing!
Edit: Turns out, while reloadData causes the crash, the crash does not occur without my custom tableViewCell... hmmm, something about removing the + sign, but it doesn't happen with deletion!
Actual error is this:
[CustomTableViewCell _accessibilityUpdateRemoveControl]: message sent to deallocated instance.
What's funny is, the remove button works. Essentially it removes the item from an array, adds it to another, basically putting it "to another table". No crashing, works fine.
If I remove the line that reloads the data in the table, after the insert button adds it, it also works. Eg: Don't immediately reload the data, close window, come back, everything displays fine. The exact line, so far, that crashes it is in
[theTable reloadData], but that line, for the other table (as I update both) doesn't crash at all. Actually, thanks to that, I'm gonna view the headers for UITableView's functions, and view other answers with that specific line. I just didn't see this, anywhere, after searching for that weird function call.
I'm ensuring my cell is within memory, and even quit dequeuing just to ensure it's working. I'm stumped with this, hopefully will have solution in an hr or less.
Thanks
I stepped through Apple's code, line by line, read the name of every function and noticed this:
editControlWasClicked: (id) clicked
is called just before crashing. I combined that with the error message, and the fact I call [table2 reloadData] before this is called, and pieced those pieces together.
The cell is erased (so it moves to the other table), but somehow calls its system callBack "editControlWasClicked" after the table reloads... since it's on the main thread, I'm guessing the table stuff is multi-threaded... how else would it call these in order but do that After the reload??
So to test this, I used the "afterDelay" function, and low and behold, it worked.
You may be asking why I'm using an add edit control in one and subtract in the other... there is a purpose to that.
So, possible solutions: 1) use the afterDelay method of selectors.
2) Write a custom IBAction ('cause it's a xib) or otherwise use custom images and functions to ensure that doesn't get called back.
Note, 2 involves writing an extra delegate so that messages from the cell can reach the view controller.
Basic solution: use iOS 5, use the queuing, otherwise do one of the above solutions or figure out the threading/hooks and find a way to do this without delaying. (I would prefer such if I can find it)
Related
I must be missing something really basic here, but I don't even know how to simply describe the problem. I designed my view controller layout in my storyboard, just a bunch of image views, labels, constraints, etc. All static - the only change the code makes is to add round edges to the buttons (UIViews), but I've also tried without that code with no difference made.
Once my segue is followed to the second view controller, it displays like this on the iPhone:
I've gotten it to display properly in 2 cases (most of the time):
Waiting. Anywhere between 30sec to 10min. Very unpredictable
Pressing the home button then resuming the app. Sometimes the text still won't show up when I do this.
Either way, this is what it's supposed to look like:
It doesn't lag or anything as the UI is completely usable even when it's not displaying properly. The images are not very large (biggest is around 300x600) so I doubt that is an issue. Image size also wouldn't account for why the text isn't displaying either. Do UIImageViews load their images asynchrounously?
I thought it might have been that the views needed refreshing because of the exit/resume behaviour. I tried [eachView setNeedsDisplay] with no success.
Any ideas?
-- UPDATE 1 --
Here is an image of my storyboard. As I said, everything is highly static. I have no idea why it's not displaying.
-- Update 2 --
I tried adding my image files to a bundle as suggested:
Then tried to reference them pragrammatically in the viewDidLoad method:
// Interface
#property (weak, nonatomic) IBOutlet UIImageView *backgroundImage;
// viewDidLoad
self.backgroundImage.image = [UIImage imageNamed:#"background.png"];
No difference unfortunately.
I have had this issue using an xcassets file. It tends to work just fine if I just add them to the bundle directly in a group. Check out this thread for some more details.
Impossible to load an image in xcassets on bundle
Here's what the problem was for those having the same issue. The previous view controller to the problem screen was a login screen. After receiving credentials, the controller would asynchronously hit the server to validate them. The response from the server was then handled in a callback function called by the networking thread. This meant that the segue was being invoked off of the main thread. Oddly enough, the segue still performed fine I guess it just took a while for the main thread to realize what was happening.
TLDR: Make sure to performSegue on the main thread.
Now, yes, there are hundreds of questions (and answers) of how to perform custom segues. However, and I'm no exaggerating, ALL of these answers are wrong (all 50+ I've seen)! Sorry, this might sound harsh, but the truth is, NONE of the suggested answers gives the same (correct) result as Apples built in transitions do (vertical cover etc.).
To be more specific, this is the result that's expected (confirmed with logs):
Segue begins (adds view to hierarchy, invokes viewWillAppear on destinationVC and viewWillDisappear on sourceVC and starts animation).
animation is performed for the whole duration
Segue ends (animation finished, sets the destinationVC as the current VC, either on stack or modally presented. Invokes viewDidAppear on destinationVC and viewDidDisappear on sourceVC).
In short: invoke viewWillAppear/Disappear -> animate transition -> invoke viewDidAppear/Disappear
Using apples built-in segues, this is the expected behavior but somehow not a single soul except me have had issues with this. A lot of versions even add the destination-view as subview first, animates it then removes it again and calls
[srcVC presentModalViewController:destVC animated:NO];
or
[srcVC.navigationController pushViewController:destVC animated:NO];
causing the view-events to be sent in all kinds of random order (same issue with CoreAnimations).
In my case, all I really want is the "Vertical Cover"-transition reverted (top to bottom), with all other events sent EXACTLY as expected (shown above).
So, am I just supposed to live with all kinds of ugly workarounds (doing my "tasks" in hard-coded methods called whenever I need them to etc.), or is there some hidden proper way of doing this in a reusable manner?
Funny thing: Even apple suggest that you do it the "wrong" way, making it seem like the right way but with inconsistent outcome compared to their own ways… So my best guess is that apple do this under the hood, and forgot to give enough flexibility for clients to perform the same operations (big flaw in other words), or that I'm just on some bad trip and see some issue that doesn't exist…
Okay, this might not be a true answer of how to solve it for custom segues (subclassing UIStoryboardSegue), but it does solve the general issue!
After some casual reading about new features, I stumbled upon a new way to do custom transitions between ViewControllers introduced in iOS7 called nothing more than "Custom Transitions" i guess!
Read about it here and here, or video from WWDC here.
I've just dipped my toes, but basically it is a new, closer to the system way of doing transitions and allows for better control = better looking transitions. After glancing at the example provided by the blog I referenced (git found here) I can confirm that FINALLY, we are able to do transitions which behave as ONE EXPECTS THEM TO with events fired at the expected occasions!
Since I'm just reading about it I can't give a thorough explanation yet, but check out the links :)
Note: This is maybe not supposed to completely replace custom segues, but can be used in a similar fashion (check examples) so if you need that little extra fancy transition, this is definitely the way to go by the looks of it! Basically you setup segues in the storyboard, and hook up the correct transition-delegates in the prepareForSegue:-method.
I have a simple app that consists of a sidebar menu (I'm using SWRevealViewController) which contains a table view, each cell of which has a segue pointing to a UIWebViewController. So the user can pull open the sidebar and switch between various configured mobile sites (among other things).
I've got it working fine, but I've noticed that, as I switch back and forth between the sidebar tabs, the number of controllers that get pinged during a memory warning keeps growing. It appears that a new UIWebVewController is created each time I switch tabs, which is fine, except that the framework code appears to be keeping a list of each controller that is created and is never letting go, causing the memory to keep climbing. I'm sure there's a way that I can clean up that list, but I haven't found it yet…
So, my questions are
What is it that is holding on to references to each UIViewController that is created, and where can I find/access that?
How do I clean that up?
What framework code/class is in charge of calling didReceiveMemoryWarning:, and where does that guy get the list of controllers that need to receive the warning?
In searching around, I came across this StackOverflow question, which hints that popViewControllerAnimated: might be how I can cleanup unneeded controllers, but I'm not sure which object I should be calling that on, since I don't know the answer to #1 or #3 above...
It turns out, in my case, the thing holding a reference to my controllers (question #1) was a scheduled NSTimer that the controller was creating with itself as the target. To clean it up (question #2), I needed to invalidate the timer prior to leaving the controller (in my case, in the viewWillDisappear: method) via [myTimer invalidate].
I still haven't found the answer to question #3, and I'm still curious to know how Apple keeps track of which controllers are still alive and, therefore, need the memory warning, but question #3 isn't as important to me, anymore, now that my memory leak is gone. :)
Check if SWRevealViewController is holding on to the View Controller it is pushing on the stack. Usually you would create a dictionary of UINavigationControllers each one for your ViewController and then use the dictionary to retrieve the UINavigationControllers each time you need it.
I am using AQGridView with Xib file. I have set the basic Project just as explained in the Video by Evadne Wu. And i am moving to next Grid using expandFromRect from ExpansionDemo and the Grid is loaded fine but whenever i click anywhere on the grid i get EXC_BAD_ACCESS and exception is generated without any Log about the reason.
Also that the didSelectItemAtIndex doesn't get called even though i have set the self.gridView.delegate = self;
self.gridView.dataSource = self;
Try this.
EDIT: This usually ensures that the delegate methods are getting called. :)
Finally it is resolved. One thing that i haven't read Known Bugs while setting up AQGridView i.e. do not pile multiple animations on top of one another that was the main reason i was facing the issue. So, while the grid was animating i blocked start of any other grid Animation and hence the issue was resolved
I have an Application, which is a SplitViewController that has a master view on the left and the detail view on the right. One of the views (Branch Finder) is a Map view that loads a series of Annotations to the Map.
If I let the annotations load before switching to any other view (loading the annotations take takes all of 1 second) then everything is fine. However, if the user quickly switches off the Branch Finder view, whilst the annotations are being loaded, then the App will crash with the following notice:
[BranchFinder_iPad respondsToSelector:]: message sent to deallocated instance 0x807d230
Now, my thoughts are that the deallocated instance would refer to the Array (declared in the header of the view) that contains all the annotations being released and set to nil when the user leaves the BranchFinder_iPad view. This is the array that is being passed to the addAnnotations method.
[self.mapView addAnnotations:branchSites];
Has anyone else encountered an issue where leaving a view, mid-way in the add allocations and a crash occurs if the user moves to another view.
Just to clarify:
If I wait for the annotations to load, switching to any other view causes no problem.
I did have a custom annotation view, but I stripped that out of my code (to eliminate it from the mix). Doing this has not changed anything.
I have looked elsewhere for help on this issue, but a lot of the view tutorials regarding map views are single view only, so this issue hasn't arisen.
I have found a vaguely similar issue # the following: mapkit addAnnotations crashes
And finally, I have just made the jump to x-code 4. I think some of my problems are just because I'm relearning some of the things I should know.
Regards,
Nathan A
PS: I wanted to attach an image to this, but am having trouble. I don't have the reputation points to do it natively, and my workplace doesn't allow me access to any image hosting portals. I will endeavour to add an image later today.
Hey anyone who reads this.
I basically performed a rookie mistake here - for the MKMapView in my application, I had to set the delegate to nil as part of the deallocation routine within my view. THe apple documentation makes mention of this in the below document:
http://developer.apple.com/library/ios/#documentation/MapKit/Reference/MKMapViewDelegate_Protocol/MKMapViewDelegate/MKMapViewDelegate.html
For the relevant section:
Before releasing an MKMapView object for which you have set a delegate, remember to set that object’s delegate property to nil. One place you can do this is in the dealloc method where you dispose of the map view.
Not having this was only causing an issue if I switched to another view AND if the MKMapView was still being referenced in executing code, such as the addAnnotations routine.