我遇到了一个非常奇怪的崩溃,这里是回溯.
* thread #1: tid = 0x2403,0x3379516c CoreFoundation`CFHash + 8,stop reason = EXC_BREAKPOINT (code=EXC_ARM_BREAKPOINT,subcode=0xdefe) frame #0: 0x3379516c CoreFoundation`CFHash + 8 frame #1: 0x33797a9c CoreFoundation`CFBasicHashRemoveValue + 1408 frame #2: 0x337974ee CoreFoundation`CFDictionaryRemoveValue + 166 frame #3: 0x3420988e Foundation`-[NSISEngine removeConstraintWithMarker:] + 562 frame #4: 0x34211dbe Foundation`-[NSLayoutConstraint _removeFromEngine:] + 230 frame #5: 0x35a954ec UIKit`-[UIView(UIConstraintBasedLayout) _layoutEngine_willRemoveLayoutConstraint:] + 44 frame #6: 0x358488fc UIKit`__48-[UIScrollView _setAutomaticContentConstraints:]_block_invoke_0 + 148 frame #7: 0x34208882 Foundation`-[NSISEngine withAutomaticoptimizationdisabled:] + 166 frame #8: 0x35848838 UIKit`-[UIScrollView _setAutomaticContentConstraints:] + 116 frame #9: 0x35848e6c UIKit`-[UIScrollView _rememberDependentConstraint:] + 112 frame #10: 0x35a9e3ae UIKit`___updateViewDependenciesForConstraint_block_invoke_0 + 30 frame #11: 0x35a954ba UIKit`_updateViewDependenciesForConstraint + 202 frame #12: 0x35a953da UIKit`-[UIView(UIConstraintBasedLayout) _layoutEngine_didAddLayoutConstraint:roundingAdjustment:mutuallyExclusiveConstraints:] + 154 frame #13: 0x35a95534 UIKit`-[UIView(UIConstraintBasedLayout) _tryToAddConstraintWithoutUpdatingConstraintsArray:roundingAdjustment:mutuallyExclusiveConstraints:] + 36 frame #14: 0x3567c2e0 UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] + 376 frame #15: 0x356d34fe UIKit`-[UIScrollView _didMoveFromWindow:toWindow:] + 50 frame #16: 0x3567c5c6 UIKit`-[UIView(Internal) _didMoveFromWindow:toWindow:] + 1118 frame #17: 0x35676e52 UIKit`-[UIView(Hierarchy) _postMovedFromSuperview:] + 138 frame #18: 0x3565e7dc UIKit`-[UIView(Internal) _addSubview:positioned:relativeto:] + 1300 frame #19: 0x3565e2c2 UIKit`-[UIView(Hierarchy) addSubview:] + 30 frame #20: 0x356f68e8 UIKit`-[UITransitionView transition:fromView:toView:removeFromView:] + 972 frame #21: 0x35937618 UIKit`__91-[UIWindowController transition:fromViewController:toViewController:target:didEndSelector:]_block_invoke_0238 + 388 frame #22: 0x357499b8 UIKit`-[UIWindowController transition:fromViewController:toViewController:target:didEndSelector:] + 4824 frame #23: 0x357b9814 UIKit`-[UIViewController _dismissViewControllerWithTransition:from:completion:] + 1708 frame #24: 0x357057c4 UIKit`-[UIViewController dismissViewControllerWithTransition:completion:] + 912 frame #25: 0x000ccd40 Capture`-[INFTagSearchViewController cancelButtonTouched:](self=0x1f09ed50,_cmd=0x001b9d5f,sender=0x1e0265c0) + 76 at INFTagSearchViewController.m:48 frame #26: 0x357470c4 UIKit`-[UIApplication sendAction:to:from:forEvent:] + 72 frame #27: 0x35747076 UIKit`-[UIApplication sendAction:toTarget:fromSender:forEvent:] + 30 frame #28: 0x35747054 UIKit`-[UIControl sendAction:to:forEvent:] + 44 frame #29: 0x3574690a UIKit`-[UIControl(Internal) _sendActionsForEvents:withEvent:] + 502 frame #30: 0x35746e00 UIKit`-[UIControl touchesEnded:withEvent:] + 488 frame #31: 0x3566f5f0 UIKit`-[UIWindow _sendtouchesForEvent:] + 524 frame #32: 0x3565c800 UIKit`-[UIApplication sendEvent:] + 380 frame #33: 0x3565c11a UIKit`_UIApplicationHandleEvent + 6154 frame #34: 0x373655a2 GraphicsServices`_PurpleEventCallback + 590 frame #35: 0x373651d2 GraphicsServices`PurpleEventCallback + 34 frame #36: 0x33829172 CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE1_PERFORM_FUNCTION__ + 34 frame #37: 0x33829116 CoreFoundation`__CFRunLoopDoSource1 + 138 frame #38: 0x33827f98 CoreFoundation`__CFRunLoopRun + 1384 frame #39: 0x3379aebc CoreFoundation`CFRunLoopRunSpecific + 356 frame #40: 0x3379ad48 CoreFoundation`CFRunLoopRunInMode + 104 frame #41: 0x373642ea GraphicsServices`GSEventRunModal + 74 frame #42: 0x356b0300 UIKit`UIApplicationMain + 1120 frame #43: 0x000a297c Capture`main(argc=1,argv=0x2fd60cfc) + 116 at main.m:16 frame #44: 0x3bb2bb20 libdyld.dylib`start + 4
你会注意到第25帧是我的代码唯一的调用,它是cancelButtonTouched,看起来像.
- (IBAction)cancelButtonTouched:(id)sender { [self dismissViewControllerAnimated:YES completion:nil]; }
我不知道发生了什么,我之前从未遇到过这样的问题,基于系统调用它似乎是一个自动布局问题.我确认在崩溃发生之前在呈现视图控制器上调用了viewWillApper,因此我假设它是在呈现视图的布局期间发出的.
关于如何将此问题缩小到特定布局约束的任何想法?还是其他任何想法?
这在某些设备上是可重现的,与其他设备一样,它很少发生.所以这是间歇性的.
更新
断点的截图.
更新2
所以它绝对是一个问题,解雇了presentationViewController,解雇两个级别深([self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:nil])工作正常,但显然不是理想的结果,我只想回到1级.这进一步让我相信存在一个“重新铺设”观点的问题.
解决方法
基于Carl Lindberg的想法,我准备并使用了以下iOS类别,我不再崩溃了:
UIView AddSubviewWithRemovingFromParent.h
#import <UIKit/UIKit.h> @interface UIView (AddSubviewWithRemovingFromParent) - (void)addSubviewWithRemovingFromParent:(UIView *)view; @end
UIView AddSubviewWithRemovingFromParent.m
#import "UIView+AddSubviewWithRemovingFromParent.h" @implementation UIView (AddSubviewWithRemovingFromParent) - (void)addSubviewWithRemovingFromParent:(UIView *)view { if (view.superview != nil) { [view removeFromSuperview]; } [self addSubview:view]; } @end
现在你可以使用addSubviewWithRemovingFromParent方法添加subView而不是addSubview方法,如下所示:
UITableViewCell *cell = [[UITableViewCell alloc] init]; [cell.contentView addSubviewWithRemovingFromParent:<viewToAdd>];
把它们加起来:
>在应用程序的控制器中查找addSubView的所有引用崩溃了>导入类别UIView AddSubviewWithRemovingFromParent.h>使用方法addSubviewWithRemovingFromParent而不是addSubView