我对 Swift 很陌生 - 在执行在 PDFView 中显示文档的简单任务时遇到了一些麻烦。我没有使用故事板或IBOutlets等。知道为什么下面崩溃了吗？
我尝试引用外部链接，但它给了我同样的错误。PDF 存在于捆绑目录中。
导入 UIKit 导入 PDFKit
类视图控制器： UIViewController {
private var pdfView = PDFView()
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
let myNewView = PDFView(frame: CGRect(x: 10, y: 100, width: 500, height: 500))
// Add border to UIView
myNewView.layer.borderWidth=2
// Change UIView Border Color to Red
myNewView.layer.borderColor = UIColor.red.cgColor
guard let path = Bundle.main.path(forResource: "CV", ofType: "pdf") else { return }
let url = URL(fileURLWithPath: path)
let document = PDFDocument(url: url)
myNewView.document = document
// Add UIView as a Subview
self.view.addSubview(myNewView)
}
}
生成成功。但我得到以下内容。
2019-06-13 17：49：35.702174+0100 Appp[81235：19343962]* 由于未捕获的异常"CALayer无效几何"而终止应用程序，原因："CALayer 位置包含 NaN：[nan nan]" *第一次抛出调用堆栈： ( 0 核心基金会0x00000001083446fb异常预处理 + 331 1 利比亚博博杰克。A.迪利布 0x0000000106250ac5 objc_exception_throw + 48 2 核心基金会 0x0000000108344555 +[NSException raise：format：] + 197 3 石英芯 0x000000010b4072ae _ZN2CA5Layer12set_positionERKNS_4Vec2IdEEb + 140 4 石英核心 0x000000010b3f668b -[CALayer setPosition：] + 57 5 石英芯 0x000000010b3f6de3 -[CALayer setFrame：] + 560 6 PDFKit 0x0000000107135097 -[PDFPageLayerTile initWithFrame：forPageLayer：withRenderingTransform：tileContentScale：generationID：] + 168 7 PDFKit 0x000000010713a805 -[PDFPageLayer _updateTiles] + 3439 8 PDFKit 0x0000000107135d8e -[PDFPageLayer setNeedsTilesUpdate] + 87 9 PDFKit 0x000000010714a97d -[PDFPageView setNeedsTilesUpdate] + 48 10 PDFKit 0x000000010714c816 -[PDFPageView setFrame：] + 334 11 PDFKit 0x000000010714311c -[PDFDocumentView createPageViewForPageAtIndex：] + 764 12 PDFKit 0x0000000107144326 -[PDFDocumentView updateVisibility] + 1726 13 PDFKit 0x00000001071b376f -[PDFView resizeDisplayView：] + 517 14 PDFKit 0x00000001071accdf -[PDFView layoutDocumentView] + 464 15 PDFKit 0x00000001071a836a -[PDFView setDocument：waitDuration：] + 1246 16 Appp 0x000000010596c4d1 $s 7Appp14ViewControllerC11viewDidLoadyyF + 1441 17 Appp 0x000000010596c7b4 $s 7Appp14ViewControllerC11viewDidLoadyyFTo + 36 18 UIKitCore 0x000000010d0ec43b -[UIViewController loadViewIfRequired] + 1183 19 UIKitCore 0x000000010d0ec868 -[UIViewController view] + 27 20 UIKitCore 0x000000010d724c33 -[UIWindow addRootViewControllerViewIfPossible] + 122 21 UIKitCore 0x000000010d725327 -[UIWindow _setHidden：forced：] + 289 22 UIKitCore 0x000000010d737f86 -[UIWindow makeKeyAndVisible] + 42 23 UIKitCore 0x000000010d6e7f1c -[UIApplication _callInitializationDelegatesForMainScene：transitionContext：] + 4555 24 UIKitCore 0x000000010d6ed0c6 -[UIApplication _runWithMainScene：transitionContext：completion：] + 1617 25 UIKitCore 0x000000010cf326d6 __111-[__UICanvasLifecycleMonitor_Compatability _scheduleFirstCommitForScene：transition：firstActivation：complete：]_block_invoke + 904 26 UIKitCore 0x000000010cf3afce +[_UICanvas _enqueuePostSettingUpdateTransactionBlock：] + 153 27 UIKitCore 0x000000010cf322ec -[__UICanvasLifecycleMonitor_Compatability _scheduleFirstCommitForScene：过渡：第一次激活：完成：] + 236 28 UIKitCore 0x000000010cf32c48 -[__UICanvasLifecycleMonitor_Compatability activateEventsOnly：withContext：completion：] + 1091 29 UIKitCore 0x000000010cf30fba __82-[_UIApplicationCanvas _transitionLifecycleStateWithTransitionContext：完成：]_block_invoke + 782 30 UIKitCore 0x000000010cf30c71 -[_UIApplicationCanvas _transitionLifecycleStateWithTransitionContext：完成：] + 433 31 UIKitCore 0x000000010cf359b6 __125-[_UICanvasLifecycleSettingsDiffAction performActionsForCanvas：withUpdateScene：settingsDiff：fromSettings：transitionContext：]_block_invoke + 576 32 UIKitCore 0x000000010cf36610 _performActionsWithDelayForTransitionContext + 100 33 UIKitCore 0x000000010cf3571d -[_UICanvasLifecycleSettingsDiffAction performActionsForCanvas：withUpdateScene：settingsDiff：fromSettings：transitionContext：] + 22334 UIKitCore 0x000000010cf3a6d0 -[_UICanvas 场景：didUpdateWithDiff：transitionContext：completion：] + 392 35 UIKitCore 0x000000010d6eb9a8 -[UIApplication workspace：didCreateScene：withTransitionContext：completion：] + 514 36 UIKitCore 0x000000010d2a2dfa -[UIApplicationSceneClientAgent scene：didInitializeWithEvent：completion：] + 361 37 前板服务 0x00000001135df125 -[FBSSceneImpl _didCreateWithTransitionContext：完成：] + 448 38 FrontBoardServices 0x00000001135e8ed6 __56-[FBSWorkspace client：handleCreateScene：withCompletion：]_block_invoke_2 + 283 39 前板服务 0x00000001135e8700 __40-[FBSWorkspace _performDelegateCallOut：]_block_invoke + 53 40 libdispatch.dylib 0x00000001096d7db5 _dispatch_client_callout + 8 41 libdispatch.dylib 0x00000001096db2ba _dispatch_block_invoke_direct + 300 42 前端板服务 0x000000011361a146 __FBSSERIALQUEUE_IS_CALLING_OUT_TO_A_BLOCK+ 30 43 前板服务 0x0000000113619dfe -[FBSS天线队列 _performNext] + 451 44 前板服务 0x000000011361a393 -[FBSS天线队列 _performNextFromRunLoopSource] + 42 45 核心基金会0x00000001082abbe1 CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION+ 17 46 核心基金会 0x00000001082ab463 __CFRunLoopDoSources0 + 243 47 核心基金会 0x00000001082a5b1f __CFRunLoopRun + 1231 48 核心基金会 0x00000001082a5302 CFRunLoopRunspecific + 626 49 图形服务 0x00000001107c62fe GSEventRunModal + 65 50 UIKitCore 0x000000010d6eeba2 UIApplicationMain + 140 51 应用程序0x000000010596f68b主 + 75 52 libdyld.dylib 0x000000010974c541 开始 + 1 53 ??? 0x0000000000000001 0x0 + 1 ) libc++abi.dylib：以 NSException 类型的未捕获异常终止 (分行)
如果将myNewView.document = document移动到viewDidAppear:而不是viewDidLoad，文档将毫无问题地加载。
不幸的是，在 12.1 和 12.2 之间对 iOS 进行了更改，因此有必要这样做。