I've got a UIPageViewController set up paging my ImageViewController.
The ImageViewController contains a UIScrollView with a UIImageView inside. Nothing else.
I'm testing at the moment with 3 "items" in my datasource for the UIPageViewController (i.e. three pages).
It all works fine and I can scroll and zoom and then page for about 30 seconds and then suddenly I get this warning...
*** Assertion failure in -[_UIQueuingScrollView _didScrollWithAnimation:force:], /SourceCache/UIKit/UIKit-2372/_UIQueuingScrollView.m:778
I've got no idea where to start debugging it though as it doesn't point to any of my code and there isn't any of my code in the stack or anything.
Can someone give me a pointer as to where to start debugging this.
EDIT
I've done a bit more testing. It seems to happen if the scrollView is decelerating (i.e. after a flick) and then I try to transition the PageViewController to another ViewController as the scrollview is still moving.
The app crashes about 20% of the way through the transition to the next page.
EDIT 2
The error seems to stop on the line _cache_getImp (not sure if that's a capital i or lowercase L).
EDIT 3
This gets better. I just downloaded Apple's PhotoScroller sample app to see if they got round the problem a different way. Well, no, they didn't. The sample app crashes in exactly the same way mine does! You have to zoom and scroll and transition pages at the same time to make it more likely to crash but it happens on it's own too it just might take longer to happen.
Came up with a solution! In my case I have a UIPageViewController with UIPageViewControllerTransitionStyleScroll as well as next buttons that allow the user to advance through my viewpager by tapping. I am getting this crash when the user presses a next button and drags around slightly before releasing their finger (still within the frame of the button). It appears that the dragging within the button is interfering with UIPageViewController's pan gesture recognizer in this case, and that's what causes the crash.
While it's pretty unlikely that the user will get in this state, I've come up with a relatively simple solution the prevents my app from crashing if it does happen. I have a boolean that represents if the user is in a valid state to move to the next screen and set it to YES on touch down, then to NO if the user drags anywhere inside my button. Then, on touchUp (nextPressed) I check the boolean before moving my UIPageViewController programatically.
- (IBAction)touchDown:(id)sender
{
self.shouldAdvanceToNextScreen = YES;
}
- (IBAction)touchDragInside:(id)sender
{
self.shouldAdvanceToNextScreen = NO;
}
- (IBAction)nextPressed:(id)sender
{
if (self.shouldAdvanceToNextScreen) {
UIViewController *initialViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"TutorialScreen2"];
NSArray *viewControllers = [NSArray arrayWithObject:initialViewController];
[self.pageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:nil];
}
}
The downside is that nothing will happen even though the user still released their finger within the button frame. However, I prefer this over a crash and see this as a pretty rare edge case regardless. I'd expect the user would just tap again - this time without a tap & drag - and move forward successfully.
I'd welcome any ideas on taking this a step further and preventing the clash between the touch drag and the UIPageViewController altogether.
Have you tried disabling bouncing in the UIScrollView? That worked for me and solved my other problem too alluded to in my comment above.
I have been fighting with this all day.
My Conclusions:
If you have a scrollview as the showing ViewController and you are delegate of the scrolls: you're in trouble. Even with the PageViewController configured with Horizontal scrolling, a vertical scrolling on your view will trigger an event. -> this does not cause trouble if: you scroll back to the top of your view before (Not sure how to fix this).
There are good StackOverflow threads like this one.
Basically the solution is:
1 [yourView setViewControllers:yourControllers direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:nil];
2 Use UIPageViewControllerTransitionStylePageCurl as the transition Style.
This fixed most of my problems.
If someone has a solution for the delegation problems with the scrolling, will be most wellcome
I had a similar problem. My setup was a UIPageViewController and I was loading view controllers with an UIImageView inside. When interacting while the UIPageViewController was scrolling I got the same crash log.
I fixed it by creating a UILongPressGestureRecognizer and add to the UIPageViewController's scroll view.
Created my own subclass of UIPageViewController (Solution is specific for my case but can easily used as a generic solution)
Find the inner UIScrollView of the UIPageViewController
- (UIScrollView *)findScrollView
{
UIScrollView *scrollView;
for (id subview in self.view.subviews)
{
if ([subview isKindOfClass:UIScrollView.class])
{
scrollView = subview;
break;
}
}
return scrollView;
}
Add the long tap gesture recognizer to the inner scroll view and point its action to a method or nil
/**
* On tap-hold the page view controller crashes as soon as it pages to a new view controller.
* Setting a long press gesture to ignore the hold.
*/
- (void)listenForLongPressGestureOnScrollView:(UIScrollView *)scrollView
{
UILongPressGestureRecognizer *longPressGestureRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:nil];
[longPressGestureRecognizer setMinimumPressDuration:0.5];
[scrollView addGestureRecognizer:longPressGestureRecognizer];
}
It surely looks like a bug in iOS 8 and 9.
(and the "answers" down below attempt to work around that)
Feel free to file a ticket on bugreport.apple.com
Do be sure to specify how to crash PhotoScroller
Include all iOS versions you've seen it crash on
To date I've seen:
Assertion failure in -[XXX.TrackingPageViewController queuingScrollView:didEndManualScroll:toRevealView:direction:animated:didFinish:didComplete:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit/UIKit-3512.60.12/UIPageViewController.m:2028
Assertion failure in -[_UIQueuingScrollView _didScrollWithAnimation:force:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit/UIKit-3512.60.12/_UIQueuingScrollView.m:785
(lldb)
I'll keep the list updated (Despite the downvoting, however massive).
Stay tuned.
It does not look like our bug.
UPD 2016 09 27 (on Xcode 8 now):
Assertion failure in -[XXX.TrackingPageViewController queuingScrollView:didEndManualScroll:toRevealView:direction:animated:didFinish:didComplete:], /SourceCache/UIKit/UIKit-3347.44.2.2/UIPageViewController.m:1875
awesome
Related
I have a pan gesture that I have added on my app's root view controller on the 1st level to let the user swipe anywhere to go to the previous level in the navigation stack (the gesture is not on the 0 level to prevent going into a black hole :) ). This has worked and still works perfectly fine on iOS versions prior to 7.
When I try to swipe back using iOS 7, I get these messages in the console:
[11050:a0b] nested pop animation can result in corrupted navigation bar
[11050:a0b] Finishing up a navigation transition in an unexpected state. Navigation Bar subview tree might get corrupted.
At this point, the app hasn't crashed.
Then when I try to swipe back one more time to the previous level, it crashes. I'm just trying to figure out why this bug has risen in iOS 7, and how I can fix it. Any help is duly and greatly appreciated!
Here is my code:
RootViewController.m:
- (void)viewDidLoad
{
[super viewDidLoad];
UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(pop:)];
pan.delegate = self;
[self.view addGestureRecognizer:pan];
}
- (void)pop:(UIPanGestureRecognizer*)pan
{
if (pan.state == UIGestureRecognizerStateBegan || pan.state == UIGestureRecognizerStateChanged)
{
CGPoint vel = [pan velocityInView:self.view];
if (vel.x > 1000)
{
[self.navigationController popViewControllerAnimated:YES];
}
}
}
I suspect the problem is your state condition. By testing for UIGestureRecognizerStateBegan and UIGestureRecognizerStateChanged, the delegate is triggering many pops (which are animated, so the next pop is triggered while the previous one is still animating).
Instead, test if (pan.state == UIGestureRecognizerStateEnded) to get just the one you need.
Also, don't worry about popping into nowhere when the NavVC is already at root. It's smart enough not to pop the root.
(As to why this is misbehaving in os7 only, I can only speculate that < ios7 logic removes the gesture recognizers at an earlier stage in the pop process).
If there is a back button visible for the current controller in the UINavigationController's stack, the user will be able to swipe right from the left edge of the screen to go back. You may want to consider not adding the pan gesture recognizer if the app is running on iOS7.
You can check the iOS version using [UIDevice currentDevice].systemVersion.
I realize your question stated that you added the gesture recognizer to allow the user to swipe anywhere to go back, but (hopefully) iOS7 users will quickly become familiar with the swipe from the left edge of the screen.
The thing happening when the velocity reaches 1000 its gonna pop the viewcontroller everytime the function is called and when its animated is YES it will get called several times before it pops the viewcontroller which I think gives you the crash.
I am trying to just do a simple view change for proof of concept.
here is the code
- (void)swipedScreen
{
if (self.secondView.superview == nil) {
[myView removeFromSuperview];
[self.view insertSubview:secondView atIndex:0];
}
}
when I swipe the screen what happens is the view area just goes black... and becomes unresponsive.
I started with a navigatoin app, replaced the tableview with just a standard uiviewcontroller class.. that worked fine..Then i added a secondView (xib only) and changed its class to match the viewcontroller of the first view.
The reason I am finding this difficult is because i am trying to animate the views inside the navigation controller and not push a whole view onto the stack which I am used to doing.
I'll bet that blank unresponsive view is, in reality, your secondView object. I always test by setting [secondView setBackgroundColor:[UIColor greenColor]] and checking if the massive green rectangle actually shows up.
EDIT: having looked at your code, there are multiple problems that arose:
You never actually +alloc or -init anything.
You never actually touch those nibs or make a reference to them in code
You declare two UIView's as IBOutlets and Strong (two exact opposites, as IBOutlets are __weak, __unsafe_unretained, or assign), yet do not link them to anything.
I've taken the liberty of revising it (sans nibs). Take a look.
Did you init the secondView? if init,you can try to set frame for the secondView
Your inserting the view at the bottom of the stack,
[self.view insertSubview:secondView atIndex:0];
Try using addSubview instead. Also you need to set the views frame somewhere.
I have a nice little app on the app store that does pretty well for itself. Life was great until iOS 5 came to town. Now, I have a number of issues with my app that I have no way of fixing because I have no clue what is going on, because I feel that they are iOS 5 issues, not mine.
Was there an iOS 5 conversion manual I missed? Or did they just change everything for fun, and want us to figure out where all the easter eggs were?
Here is another issue I am experiencing (that I have wasted so much time trying to fix), that DON'T EXIST AT ALL when I simply say that I want to run the app in good ol' 4.2:
Modal view
My app is a simple reader app. I have a book reading view that displays text with a UIWebView. One of the features I have been working on involves the ability to take notes as you read. This is achieved by hitting a button, and presenting a modal view. Yes, a modal view. The most simple pre- iOS 5 thing you could possibly do. Now, when I dismiss my modal view, just by hitting cancel, and simply dismiss the view, when I get back to my reader view, the navigation bar at the top is pushed up half way off the screen! This doesn't happen in 4.2, but there it is in iOS 5!
What can I do to get this issue resolved?
Thanks for your help.
Ok, I was just able to figure out what in the blazes was going on. I had the shouldAutorotateToInterfaceOrientation value set to a BOOL variable, so that when the modalView was coming back, it didn't know the state/size of the status bar. Fixed that, and the problem disappeared.
I have the feeling it has something to do with the way you present and dismissing the modalview. Apple introduced a new method to present views. May you try using theses instead of the old ones and see if it fixes your problem.
So here is what you do:
change this method:
presentModalViewController:animated:
into the new preferred method introduced with iOS 5:
presentViewController:animated:completion:
Depending if you are using dismissModalViewControllerAnimated:to dismiss your view, change it into dismissViewControllerAnimated:completion.
This methods also have completion handler which is very useful to do some extra work after the view has been presented/dismissed. Maybe that also helps with your other issue. Let me know if that might helped.
A major change in iOS 5 is that the navigationController property of UIViewController is no longer set for modal views. Instead, there is a new (not present in iOS 4) parentViewController property. So where you're using navigationController in a modal view you need to change the logic to something like:
UIViewController* parent;
if ([self respondsToSelector:#selector(parentViewController)]) {
parent = self.parentViewController;
}
else {
parent = self.navigationController;
}
(That's from memory, so I can't guarantee that every t is dotted and every i crossed.)
I was seeing this same clipping problem.
I found out that the reason for my issue was that I set the content size within the modal dialog (something I did for my iPad layout), so removing these two lines seemed to fix the issue:
CGSize size = CGSizeMake(320, 480);
self.contentSizeForViewInPopover = size;
I thought the problem was fixed but it wasn't. After reviewing the code some more, cleaning the build, and retesting it turned out to be a shouldAutorotateToInterfaceOrientation which would return NO for all orientations, for a brief amount of time (flag == NO) while the app is loading (root controller). You want to at least return YES to one orientation like so:
- (BOOL) shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation
{
return !self.flag ? UIInterfaceOrientationPortrait == toInterfaceOrientation : YES;
}
I wrote simple code to test UIImagePickerController:
#implementation ProfileEditViewController
- (void)viewDidLoad {
[super viewDidLoad];
photoTaker_ = [[UIImagePickerController alloc] init];
photoTaker_.delegate = self;
photoTaker_.sourceType = UIImagePickerControllerSourceTypeCamera;
photoTaker_.showsCameraControls = NO;
}
- (void)viewDidAppear: (BOOL)animated {
[self presentModalViewController: photoTaker_ animated: NO];
}
#end
And I'm getting strange warnings like the following:
2010-05-20 17:53:13.838 TestProj[2814:307] Using two-stage rotation animation. To use the smoother single-stage animation, this application must remove two-stage method implementations.
2010-05-20 17:53:13.849 TestProj[2814:307] Using two-stage rotation animation is not supported when rotating more than one view controller or view controllers not the window delegate
Got any idea what this is about? Thanks a lot in advance!
This message will appear if you are presenting the UIImagePickerController within another UIViewController. Because it isn't pushed like a UINavigationController stack, there is confusion at the UIWindow level. I don't know if the warning is a problem, but to eliminate the warning you can do the following:
// self = a UIViewController
//
- (void) showCamera
{
cameraView = [[UIImagePickerController alloc] init];
[[[UIApplication sharedApplication] keyWindow] setRootViewController:cameraView];
[self presentModalViewController:cameraView animated:NO];
}
- (void) removeCamera
{
[[[UIApplication sharedApplication] keyWindow] setRootViewController:self];
[self dismissModalViewControllerAnimated:NO];
[cameraView release];
}
Perhaps you are adding the root UIViewController's view as a subview of the window instead of assigning the view controller to the window's rootController property?
IT ALL FALLS BACK ON THE UI
This warning can be implemented for several different objects: Pickers, keyboard, etc.
I have found that it is related to the UI taking two steps to complete a transition or other animation. Or for any instance where the UI is trying to finish one thing and is being asked to execute another before it has finished. (therefore it covers a wide range of possible triggers)
I have seen the warning appear on 4.0 & 4.2. In my case I was working with rotating the device and catching whether the keyboard was still up-(i.e. text field was still first responder). If so, the keyboard needed to stay up for between the views, but this presented other complications with other views.
Therefore, I implemented a BOOL tracker to keep track if keybaordIsPresent, and if so I was {textfield resignFirstResponder]; when detecting the orientation change and the reset the textfield to becomeFristResponder after the transition that was wrapped in an Animation Block. My BOOL tracker worked better, I still use the NSNotifications for the Keyboard, but there were overlaps of notifications during rotations because the keyboard was being dismissed without requesting such. The BOOL is set to NO on Load, and when the [textfield resignFirstResponder]; is implemented. *not when "-(void)keyboardWillhide is trigger by the NSNotifications, which gives me both working triggers that never conflict. The BOOL is set to YES, only when the user touches textfield which automatically triggers becomeFirstResponder.
I removed the warning by taking the [textfild resignFirstResponder]; out of the
-(void)willAnimateFirstHalfOfRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
//if (keyboardIsPresent == YES) {[self.entryTextField resignFirstResponder];}
}
and placing it back at the top of the code for the:
- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation {
if (keyboardIsPresent == YES) {
[self.entryTextField resignFirstResponder];
}
//Determine Which Orientation is Present:
if((fromInterfaceOrientation == UIInterfaceOrientationPortrait) || (fromInterfaceOrientation == UIInterfaceOrientationPortraitUpsideDown)){
//LANDSCAPE VIEW:
[self configureLandscapeView];
}else {
//PORTRAIT VIEW:
[self configurePortraitView];
}
}
**Even though I had no code inside the -(void)willAnimatFirstHalfOfRotationToInterface:, the warning was still popping up. I think the warning was still popping up because the compiler still has to attempt the method while it is trying to execute the first animation and therefore gets the double animation call or overlap of resources. It doesn't know that there is no executable code with the method until after it runs through it. And by that time it already set aside resource in preparation for handling possible actions within the method.
**To ellimiate the warning I had to remove or nil out the code for the willAnimateFirstHalfOfRotation, so that the compiler does not have to even check to see if there is a possible 2nd animation or action that may need to be executed at the same time.
/*-(void)willAnimateFirstHalfOfRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration {
//if (keyboardIsPresent == YES) {[self.entryTextField resignFirstResponder];}}*/
After the transition is completed, within the original animation block I check to see if the "keyboardIsPresent" was YES prior to the rotation, and if so, I resign the First Responder once again. I use setAnimationDuration:0.3which comes out pretty clean and not jumpy.
Well, you are presenting UIImagePickerController modally inside viewDidAppear of ProfileEditViewController.
Think about this. That means when ProfileEditViewController view appears, the UIImagePickerController appears, say later you dismiss UIImagePickerController and it goes back to ProfileEditViewController, then viewDidAppear is called again and UIImagePickerController appears, say later you dismiss UIImagePickerController and it goes back to ProfileEditViewController, then viewDidAppear is called again and.... you get the idea.
That warning is rather cryptic though, not sure if that is what it's trying to tell you. I would suggest making a button somewhere on the ProfileEditViewController that calls presentModalViewController and also make sure you have a way to dismiss the UIImagePickerController (I've never used it not sure if it has one automatically).
You may be trying to present two modal view controllers at the same time, and they are fighting for animation resources.
1) There is rarely any UI reason to do this. You could instead just go directly to the second view controller (the image picker); and, after dismissing it, then present the first view or view controller.
2) If you do want two stacked view controllers or a view controller on top of a view, then set a timer in viewDidAppear to present the second view controller after the first one has finished it's animation. (You could display a dummy png image of a blank picker in the first one to prevent too much display flashing until the second view controller goes live.)
EDIT - Added a random code example:
I might try substituting this as an experiment:
- (void)foo {
[self presentModalViewController: photoTaker_ animated: NO];
}
- (void)viewDidAppear: (BOOL)animated {
NSTimer *bar = [ NSTimer scheduledTimerWithTimeInterval: (2.0f)
target: self
selector: #selector(foo)
userInfo: nil
repeats:NO ];
}
A shorter time delay may work as well.
I just had the same problem. In my case was a silly mistake that I'm putting here just in case anyone else falls into that same issue.
In my tabbed app I remove one of the original ViewControllers and added a new one with Storyboard to create a "Settings" section.
This new VC had to be a table view VC and even I designed, compiled and run it without a problem, when I changed the orientation of the app I kept getting this “Using two-stage rotation animation” error.
My problem was that I forgot to change in the original .h file interface "UIViewController" for "UITableViewController".
Once this was done I changed on the Storyboard identity badge the class from the general value to my SettingsViewController and that was the end of it.
I hope it can help someone else. It took me a while to get to bottom of this.
Cheers,
I think the warning here is about Core Animation performance. As a test, I loaded the image picker without any action sheet or other animations going on and the warnings are still there. I think these are warnings coming from the image picker class itself and not from any misuse of the API.
So in my app delegate I add a call add the myViewController.view to the main window:
1. [window addSubview:myViewController.view];
In myViewController I do the following code in the viewDidAppear method:
2. [self presentModalViewController: yourViewController animated: YES];
In my yourViewController class I do the following to try and go back to the main window
3. [self dismissModalViewControllerAnimated:YES];
My main windows view appears with buttons in all, but the buttons won't react to any click or anything. It's like there is something over them that I can't see.
Also, the main windows button works before this process but doesn't after the process.
Any help would be appreciated.
If the dismiss method call is in the modal view controller (not the parent that presents it), then you actually want to call [self.parentController dismissModalViewControllerAnimated:YES];
There are a number of reasons why things might not be responding to your touches. Here are two that have happened to me:
The frame of the view you want to touch is too small. UIViews can draw outside of their frames, so it might look ok, but not respond if the touch is technically outside of the frame -- you also have to check that all the superview's up the hierarchy also have a large enough frame.
If anything in your view is a UIImageView or child thereof, it won't respond to user touches because UIImageView has userInteractionEnabled set to NO by default. You can fix this just by setting myImageView.userInteractionEnabled = YES;
Edit: Oli pointed out in the comments that dismissModalViewControllerAnimated: should work if called on either self.parentController or simply self, since that method is smart enough to call the parent if needed, according to the docs. The docs also make it sound like this might behave differently if you have multiple model views open at once, though, so I would still consider it cleaner code to call the method on self.parentController directly.