2 Replies
      Latest reply on Nov 7, 2019 11:42 PM by Claude31
      bubaichifan Level 1 Level 1 (0 points)

        hi,

        I got an crash in my App(only iOS11 and below), accidental appearance. Has no clue why this comes from, and how to avoid?

         

        In my viewcontroller BBANovelWiseToNAReaderVC , implemention of UIScrollViewDelegate

        - (void)scrollViewDidScroll:(UIScrollView *)scrollView {

             .....

             [self.collectionView layoutAttributesForItemAtIndexPath:bottomIndexPath]; // here crash!

             ....

        }

         

        Crash stacks:

        Thread 0 Crashed:  Queue: com.apple.main-thread 0

        UIKit  -[UICollectionViewData layoutAttributesForItemAtIndexPath:] (in UIKit) + 244 1

        UIKit  -[UICollectionView layoutAttributesForItemAtIndexPath:] (in UIKit) + 60 2

        BaiduBoxApp   -[BBANovelWiseToNAReaderVC scrollViewDidScroll:] (in BaiduBoxApp) (BBANovelWiseToNAReaderVC.m:0) 3

        UIKit  -[UIScrollView(UIScrollViewInternal) _notifyDidScroll] (in UIKit) + 76 4

        UIKit  -[UIScrollView setContentOffset:] (in UIKit) + 460 5

        UIKit  -[UIScrollViewScrollAnimation setProgress:] (in UIKit) + 308 6

        UIKit  -[UIAnimator(Static) _advanceAnimationsOfType:withTimestamp:] (in UIKit) + 280 7

        QuartzCore    CA::Display::DisplayLinkItem::dispatch() (in QuartzCore) + 40 8

        QuartzCore    CA::Display::DisplayLink::dispatch_items(unsigned long long, unsigned long long, unsigned long long) (in QuartzCore) + 424 9   IOKit      IODispatchCalloutFromCFMessage (in IOKit) + 372 10

        CoreFoundation       __CFMachPortPerform (in CoreFoundation) + 180 11

        CoreFoundation      _CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ (in CoreFoundation) + 56 12  CoreFoundation       __CFRunLoopDoSource1 (in CoreFoundation) + 436 13

        CoreFoundation        __CFRunLoopRun (in CoreFoundation) + 1800 14

        CoreFoundation      CFRunLoopRunSpecific (in CoreFoundation) + 384 15

        GraphicsServices     GSEventRunModal (in GraphicsServices) + 180 16

        UIKit              UIApplicationMain (in UIKit) + 204 17

        BaiduBoxApp        main (in BaiduBoxApp) (main.m:24) 18  ???             0x00000001816f28b8 0x0 + 0