pageViewController setViewControllers crashes with "Invalid parameter not satisfying: [views count] == 3"
xcode
Solution
I ran into the same problem, and was able to solve it using a tip from this answer https://stackoverflow.com/a/20973822/3757370. Simply placing the setViewControllers:direction:animated:completion: code inside of a dispatch_async block on the main queue fixed it for me. For you this would look like
dispatch_async(dispatch_get_main_queue(), ^{
[self.pageViewController setViewControllers:@[ [self.storyboard instantiateViewControllerWithIdentifier:_pageStoryBoardIDs[0]] ]
direction:UIPageViewControllerNavigationDirectionReverse
animated:YES completion:nil];
});
Hope it helps!
Problem
I know that there are several other questions like this, but i couldn't find a solution for my problem. I use a pageViewController which displays different ViewControllers. Every time the pageViewController moves forward I check the input of the lastPage. If it's wrong the pageViewController should go back to that page by using the setViewController method. Without this method everything works fine but if I try to use it the app crashes with the following exception: ``` 19:48:25.596 Phook[23579:60b] *** Assertion failure in -[_UIQueuingScrollView _replaceViews:updatingContents:adjustContentInsets:animated:], /SourceCache/UIKit_Sim/UIKit-2935.137/_UIQueuingScrollView.m:383 2014-06-02 19:48:25.600 Phook[23579:60b] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Invalid parameter not satisfying: [views count] == 3' ``` And here's my code: ``` - (void)pageViewController:(UIPageViewController *)pageViewController didFinishAnimating:(BOOL)finished previousViewControllers:(NSArray *)previousViewControllers transitionCompleted:(BOOL)completed { if (completed && finished) { RegisterUserPageContent* lastPage = (RegisterUserPageContent*)previousViewControllers[ previousViewControllers.count-1]; int lastIndex = lastPage.pageIndex; int newIndex = ((RegisterUserPageContent*)[self.pageViewController.viewControllers objectAtIndex:0]).pageIndex; if (newIndex > lastIndex) { // Moved Forward if(!lastPage.testInput) { [self.pageViewController setViewControllers:@[ [self.storyboard instantiateViewControllerWithIdentifier:_pageStoryBoardIDs[0]] ] direction:UIPageViewControllerNavigationDirectionReverse animated:YES completion:nil]; } } else { // Moved Reverse } } } ``` As I already said. I searched a lot and implemented some solutions but nothing helped. Thanks.