iOS11 UIPageViewController error 해결

iOS11 배포 이후 fabric에 관련 crash가 들어오기 시작했다

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UIKit

-[UIPageViewController queuingScrollView:willManuallyScroll:toRevealView:concealView:animated:]

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0	CoreFoundation	__exceptionPreprocess
1	libobjc.A.dylib	objc_exception_throw
2	CoreFoundation	+[NSException raise:format:]
3	Foundation	-[NSAssertionHandler handleFailureInMethod:object:file:lineNumber:description:]
​ 4	UIKit	-[UIPageViewController queuingScrollView:willManuallyScroll:toRevealView:concealView:animated:]
5	UIKit	-[_UIQueuingScrollView _notifyDelegateWillManuallyScroll:toRevealView:concealingView:animated:]
6	UIKit	__54-[_UIQueuingScrollView _didScrollWithAnimation:force:]_block_invoke
7	UIKit	-[_UIQueuingScrollView _didScrollWithAnimation:force:]
8	UIKit	-[_UIQueuingScrollView layoutSubviews]
9	UIKit	-[UIView(CALayerDelegate) layoutSublayersOfLayer:]
10	QuartzCore	-[CALayer layoutSublayers]
11	QuartzCore	CA::Layer::layout_if_needed(CA::Transaction*)
12	QuartzCore	CA::Context::commit_transaction(CA::Transaction*)
13	QuartzCore	CA::Transaction::commit()
14	QuartzCore	CA::Display::DisplayLink::dispatch_items(unsigned long long, unsigned long long, unsigned long long)
15	IOKit	IODispatchCalloutFromCFMessage
16	CoreFoundation	__CFMachPortPerform
17	CoreFoundation	__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__
18	CoreFoundation	__CFRunLoopDoSource1
19	CoreFoundation	__CFRunLoopRun
20	CoreFoundation	CFRunLoopRunSpecific
21	GraphicsServices	GSEventRunModal
22	UIKit	UIApplicationMain

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그래서 구글링 한 결과

https://stackoverflow.com/questions/12939280/uipageviewcontroller-navigates-to-wrong-page-with-scroll-transition-style/12939384#12939384

 

UIPageViewController navigates to wrong page with Scroll transition style

My UIPageViewController was working fine in iOS 5. But when iOS 6 came along, I wanted to use the new scroll transition style (UIPageViewControllerTransitionStyleScroll) instead of the page curl st...

stackoverflow.com

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위 링크에 따르면 error는 PageViewController 의 일종의 버그이며, PageViewController의 animation 처리때문이었고, animation을 YES로 했을 때 pageviewcontroller가 가지는 내부 캐싱과 꼬이는 현상때문이라고 판단했다

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이럴 땐

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[Objective - C]
__weak YourSelfClass *blocksafeSelf = self;     
[self.pageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:^(BOOL finished){
            if(finished)
            {
                dispatch_async(dispatch_get_main_queue(), ^{
                    [blocksafeSelf.pageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:NULL];// bug fix for uipageview controller
                });
            }
        }];

[Swift]
pageViewController.setViewControllers([page], direction: direction, animated: true) { done in
        if done {
            dispatch_async(dispatch_get_main_queue()) {
                self.pageViewController.setViewControllers([page], direction: direction, animated: false, completion: {done in })
            }
        }
    }

 

block처리를 통해 animation callback 을 받아 처리하거나,

​

 if (transitionInProgress_ == NO) {
            transitionInProgress_ = YES;
            [self.pageViewController setViewControllers: viewControllers
                                          direction:UIPageViewControllerNavigationDirectionForward
                                           animated:isAnimated
                                         completion:^(BOOL finished) {
                                             transitionInProgress_ = !finished;
                                         }];
        }

 

이와같이 bool 값을 주어 처리하면 해결된다.