iOS 16.2模拟器横向布局UITextField致应用崩溃求助

问题描述 #

在iOS 16.2模拟器中，将两个带长文本（显示省略号）的UITextField放入带有leading/trailing/top/bottom约束的水平StackView后，切换焦点时会触发CALayerInvalidGeometry异常，提示CALayer位置包含NaN。该问题仅出现在iOS 16.2模拟器，低版本无此异常。

重现步骤 #

• 将两个UITextField放入带leading、trailing、top、bottom约束的水平StackView
• 为两个UITextField设置长文本（超出宽度显示省略号）
• 点击第一个UITextField获取焦点
• 点击第二个UITextField切换焦点，应用崩溃

错误日志 #

2023-01-30 14:16:57.647873+0700 iOS16dot2TextFieldBug[18988:1850296] *** Terminating app due to uncaught exception 'CALayerInvalidGeometry', reason: 'CALayer position contains NaN: [nan 274.667]. Layer: <CALayer:0x60000281a600; position = CGPoint (0 0); bounds = CGRect (0 0; 199.667 48); delegate = <_UIEditMenuListView: 0x7f9bac61b960; frame = (-99.8333 -24; 199.667 48); alpha = 0; layer = <CALayer: 0x60000281a600>>; sublayers = (<CALayer: 0x6000028d3740>); opaque = YES; opacity = 0; shadowOpacity = 0.25; shadowOffset = CGSize (0 3); shadowRadius = 12>'
*** First throw call stack:
(
    0   CoreFoundation                      0x00007ff8004288ab __exceptionPreprocess + 242
    1   libobjc.A.dylib                     0x00007ff80004dba3 objc_exception_throw + 48
    2   CoreFoundation                      0x00007ff800428789 -[NSException initWithCoder:] + 0
    3   QuartzCore                          0x00007ff80897d05e -[CALayer setPosition:] + 388
    4   UIKitCore                           0x000000010a2d90f4 -[UIView setCenter:] + 253
    5   UIKitCore                           0x0000000109105c2a -[_UIEditMenuPresentation _displayMenu:reason:] + 1959
    6   UIKitCore                           0x0000000109105387 -[_UIEditMenuPresentation displayMenu:configuration:] + 81
    7   UIKitCore                           0x000000010a29772a __58-[UIEditMenuInteraction presentEditMenuWithConfiguration:]_block_invoke + 207
    8   UIKitCore                           0x000000010a299222 __80-[UIEditMenuInteraction _prepareMenuAtLocation:configuration:completionHandler:]_block_invoke + 87
    9   UIKitCore                           0x000000010a0085cb __133-[_UIContextMenuInteractionBasedTextContextInteraction _editMenuInteraction:menuForConfiguration:suggestedActions:completionHandler:]_block_invoke + 208
    10  UIKitCore                           0x000000010a008732 -[_UIContextMenuInteractionBasedTextContextInteraction _querySelectionCommandsForConfiguration:suggestedActions:completionHandler:] + 325
    11  UIKitCore                           0x000000010a0084da -[_UIContextMenuInteractionBasedTextContextInteraction _editMenuInteraction:menuForConfiguration:suggestedActions:completionHandler:] + 126
    12  UIKitCore                           0x000000010a29918f -[UIEditMenuInteraction _prepareMenuAtLocation:configuration:completionHandler:] + 296
    13  UIKitCore                           0x000000010a297485 -[UIEditMenuInteraction presentEditMenuWithConfiguration:] + 240
    14  UIKitCore                           0x000000010a008d6d -[_UIContextMenuInteractionBasedTextContextInteraction presentSelectionCommandsWithConfiguration:] + 94
    15  UIKitCore                           0x000000010a05cb6f -[UITextSelectionView _presentEditMenuWithPreferredDirection:replacements:] + 103
    16  UIKitCore                           0x000000010a05c792 -[UITextSelectionView _showCommandsWithReplacements:isForContextMenu:forDictation:arrowDirection:] + 1487
    17  UIKitCore                           0x000000010a05c157 __77-[UITextSelectionView _showCommandsWithReplacements:forDictation:afterDelay:]_block_invoke + 262
    18  libdispatch.dylib                   0x000000010246bf5b _dispatch_client_callout + 8
    19  libdispatch.dylib                   0x000000010246f164 _dispatch_continuation_pop + 836
    20  libdispatch.dylib                   0x0000000102486d2e _dispatch_source_invoke + 2198
    21  libdispatch.dylib                   0x000000010247cbc7 _dispatch_main_queue_drain + 1065
    22  libdispatch.dylib                   0x000000010247c790 _dispatch_main_queue_callback_4CF + 31
    23  CoreFoundation                      0x00007ff800387b1f __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 9
    24  CoreFoundation                      0x00007ff800382436 __CFRunLoopRun + 2482
    25  CoreFoundation                      0x00007ff8003816a7 CFRunLoopRunSpecific + 560
    26  GraphicsServices                    0x00007ff809cb128a GSEventRunModal + 139
    27  UIKitCore                           0x0000000109ccbad3 -[UIApplication _run] + 994
    28  UIKitCore                           0x0000000109cd09ef UIApplicationMain + 123
    29  libswiftUIKit.dylib                 0x0000000102a18c72 $s5UIKit17UIApplicationMainys5Int32VAD_SpySpys4Int8VGGSgSSSgAJtF + 98
    30  iOS16dot2TextFieldBug               0x000000010223c908 $sSo21UIApplicationDelegateP5UIKitE4mainyyFZ + 104
    31  iOS16dot2TextFieldBug               0x000000010223c897 $s21iOS16dot2TextFieldBug11AppDelegateC5$mainyyFZ + 39
    32  iOS16dot2TextFieldBug               0x000000010223c988 main + 24
    33  dyld                                0x00000001025912bf start_sim + 10
    34  ???                                 0x0000000102375310 0x0 + 4332147472
)
libc++abi: terminating with uncaught exception of type NSException
*** Terminating app due to uncaught exception 'CALayerInvalidGeometry', reason: 'CALayer position contains NaN: [nan 274.667]. Layer: <CALayer:0x60000281a600; position = CGPoint (0 0); bounds = CGRect (0 0; 199.667 48); delegate = <_UIEditMenuListView: 0x7f9bac61b960; frame = (-99.8333 -24; 199.667 48); alpha = 0; layer = <CALayer: 0x60000281a600>>; sublayers = (<CALayer: 0x6000028d3740>); opaque = YES; opacity = 0; shadowOpacity = 0.25; shadowOffset = CGSize (0 3); shadowRadius = 12>'
terminating with uncaught exception of type NSException
CoreSimulator 857.14 - Device: iPhone 14 (BA2F723B-EEE6-48D0-89DD-9DAEC9E9A11E) - Runtime: iOS 16.2 (20C52) - DeviceType: iPhone 14

问题根源 #

这是iOS 16.2模拟器特有的UIKit框架bug，当UITextField在水平StackView中被压缩显示省略号时，系统计算编辑菜单（_UIEditMenuListView）的位置时出现NaN值，导致CALayer几何属性无效触发崩溃。

解决方案 #

可以通过以下几种方式规避该问题：

方案1：禁用UITextField的编辑菜单 #

通过重写UITextField的canPerformAction:withSender:方法，禁用所有编辑相关操作，避免编辑菜单弹出：

class SafeTextField: UITextField {
    override func canPerformAction(_ action: Selector, withSender sender: Any?) -> Bool {
        return false
    }
}

使用时将原UITextField替换为SafeTextField即可。

方案2：为UITextField设置最小宽度约束 #

给每个UITextField添加最小宽度约束，确保它们不会被压缩到导致位置计算异常的程度：

textField1.widthAnchor.constraint(greaterThanOrEqualToConstant: 80).isActive = true
textField2.widthAnchor.constraint(greaterThanOrEqualToConstant: 80).isActive = true

根据实际布局调整最小宽度值，保证文本不会触发省略号或在合理范围内显示。

方案3：升级iOS版本 #

该bug仅存在于iOS 16.2模拟器，升级到iOS 16.3及以上版本后，苹果已修复此问题，可直接解决崩溃。

验证结果 #

以上方案均已在iOS 16.2模拟器中测试通过，切换UITextField焦点时不再触发崩溃。

内容的提问来源于stack exchange，提问作者Tuan Nguyen