我在滚动视图上添加UIRefreshControl，在iOS 13以下可以正常工作，但是当我在iOS 13上运行相同的应用程序时，它崩溃并显示以下日志。
在ScrollView上添加UIRefreshControl
let refresh = UIRefreshControl()
//Scroll View main
@IBOutlet weak var scrollViewMain: UIScrollView!
override func viewDidLoad() {
super.viewDidLoad()
pullToRefresh()
}
func pullToRefresh(){
refresh.addTarget(self, action: #selector(handleTopRefresh(_:)), for: .valueChanged )
refresh.tintColor = UIColor.themeAppColor
self.scrollViewMain.refreshControl = refresh
}
@objc func handleTopRefresh(_ sender:UIRefreshControl){
getOutletRatings()
}
崩溃日志
MyApp Test[33324:98294] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '<MyApp_Test.OutletRatingVC: 0x7faa2e806a00> returned nil from -traitCollection, which is not allowed.'
*** First throw call stack:
(
0 CoreFoundation 0x00007fff23b98bde __exceptionPreprocess + 350
1 libobjc.A.dylib 0x00007fff503b5b20 objc_exception_throw + 48
2 CoreFoundation 0x00007fff23b98958 +[NSException raise:format:arguments:] + 88
3 Foundation 0x00007fff255eb7be -[NSAssertionHandler handleFailureInFunction:file:lineNumber:description:] + 166
4 UIKitCore 0x00007fff46dd08bd _UIGetCurrentFallbackTraitCollection + 962
5 UIKitCore 0x00007fff476029fa UIViewCommonInitWithFrame + 617
6 UIKitCore 0x00007fff47602753 -[UIView initWithFrame:] + 98
7 UIKitCore 0x00007fff46b910bb -[_UIRefreshControlModernContentView initWithFrame:] + 70
8 UIKitCore 0x00007fff46b6343d -[UIRefreshControl _contentView] + 150
9 UIKitCore 0x00007fff46b631ab -[UIRefreshControl sizeToFit] + 52
10 UIKitCore 0x00007fff46b632b1 -[UIRefreshControl didMoveToSuperview] + 178
11 UIKitCore 0x00007fff476207de __45-[UIView(Hierarchy) _postMovedFromSuperview:]_block_invoke + 1010
12 UIKitCore 0x00007fff47620373 -[UIView(Hierarchy) _postMovedFromSuperview:] + 753
13 UIKitCore 0x00007fff4762fb45 -[UIView(Internal) _addSubview:positioned:relativeTo:] + 1718
14 UIKitCore 0x00007fff475c396d -[UIScrollView _addContentSubview:atBack:] + 564
15 UIKitCore 0x00007fff475bf3df -[UIScrollView _setRefreshControl:] + 248
16 UIKitCore 0x00007fff475bf265 -[UIScrollView setRefreshControl:] + 67
17 MyApp Test 0x000000010d5cd02e $s14MyApp_Test14OutletRatingVCC13pullToRefreshyyF + 270
18 MyApp Test 0x000000010d5cce7e $s14MyApp_Test14OutletRatingVCC11viewDidLoadyyF + 190
19 MyApp Test 0x000000010d5ccf0b $s14MyApp_Test14OutletRatingVCC11viewDidLoadyyFTo + 43
20 UIKitCore 0x00007fff46af87c2 -[UIViewController _sendViewDidLoadWithAppearanceProxyObjectTaggingEnabled] + 83
21 UIKitCore 0x00007fff46afd6d3 -[UIViewController loadViewIfRequired] + 1084
22 UIKitCore 0x00007fff46afdaf0 -[UIViewController view] + 27
23 UIKitCore 0x00007fff46a81dbf -[UIPageViewController _setViewControllers:withScrollInDirection:animated:completion:] + 538
24 UIKitCore 0x00007fff46a81fd3 -[UIPageViewController setViewControllers:direction:animated:completion:] + 263
25 CarbonKit 0x000000010e3afb01 -[CarbonTabSwipeNavigation loadFirstViewController] + 705
26 CarbonKit 0x000000010e3aaba1 -[CarbonTabSwipeNavigation initWithItems:toolBar:delegate:] + 289
27 MyApp Test 0x000000010d32960a $sSo24CarbonTabSwipeNavigationC5items7toolBar8delegateABSayypGSg_So9UIToolbarCyptcfcTO + 250
28 MyApp Test 0x000000010d32828a $sSo24CarbonTabSwipeNavigationC5items7toolBar8delegateABSayypGSg_So9UIToolbarCyptcfC + 58
29 MyApp Test 0x000000010d327159 $s14MyApp_Test15RatingMainTabVCC11viewDidLoadyyF + 409
30 MyApp Test 0x000000010d3282cb $s14MyApp_Test15RatingMainTabVCC11viewDidLoadyyFTo + 43
31 UIKitCore 0x00007fff46af87c2 -[UIViewController _sendViewDidLoadWithAppearanceProxyObjectTaggingEnabled] + 83
32 UIKitCore 0x00007fff46afd6d3 -[UIViewController loadViewIfRequired] + 1084
33 UIKitCore 0x00007fff46a6208c -[UINavigationController _updateScrollViewFromViewController:toViewController:] + 160
34 UIKitCore 0x00007fff46a6238c -[UINavigationController _startTransition:fromViewController:toViewController:] + 140
35 UIKitCore 0x00007fff46a63256 -[UINavigationController _startDeferredTransitionIfNeeded:] + 868
36 UIKitCore 0x00007fff46a645c1 -[UINavigationController __viewWillLayoutSubviews] + 150
37 UIKitCore 0x00007fff46a45ffb -[UILayoutContainerView layoutSubviews] + 217
38 UIKitCore 0x00007fff47636722 -[UIView(CALayerDelegate) layoutSublayersOfLayer:] + 2478
39 QuartzCore 0x00007fff2b030ef9 -[CALayer layoutSublayers] + 255
40 QuartzCore 0x00007fff2b0358ff _ZN2CA5Layer16layout_if_neededEPNS_11TransactionE + 517
41 QuartzCore 0x00007fff2b041fe4 _ZN2CA5Layer28layout_and_display_if_neededEPNS_11TransactionE + 80
42 QuartzCore 0x00007fff2af8a4a8 _ZN2CA7Context18commit_transactionEPNS_11TransactionEd + 324
43 QuartzCore 0x00007fff2afbfab3 _ZN2CA11Transaction6commitEv + 643
44 UIKitCore 0x00007fff4715c27c _UIApplicationFlushRunLoopCATransactionIfTooLate + 104
45 UIKitCore 0x00007fff471fd878 __handleEventQueueInternal + 6902
46 CoreFoundation 0x00007fff23afbac1 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
47 CoreFoundation 0x00007fff23afb9ec __CFRunLoopDoSource0 + 76
48 CoreFoundation 0x00007fff23afb1c4 __CFRunLoopDoSources0 + 180
49 CoreFoundation 0x00007fff23af5ecf __CFRunLoopRun + 1263
50 CoreFoundation 0x00007fff23af56b6 CFRunLoopRunSpecific + 438
51 GraphicsServices 0x00007fff3815cbb0 GSEventRunModal + 65
52 UIKitCore 0x00007fff47162a67 UIApplicationMain + 1621
53 MyApp Test 0x000000010d4769cb main + 75
54 libdyld.dylib 0x00007fff5123bcf5 start + 1
55 ??? 0x0000000000000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
答案 0 :(得分：0)
我假设您在viewDidLoad中没有特征集。将pullToRefresh（）移至viewWillAppear，然后更改pullToRefresh函数
func pullToRefresh() {
if scrollViewMain.refreshControl == nil {
refresh.addTarget(self, action: #selector(handleTopRefresh(_:)), for: .valueChanged )
refresh.tintColor = UIColor.blue
self.scrollViewMain.refreshControl = refresh
}
}