的iOS斯威夫特和Xamarin應用程序崩潰使用的UIImagePickerController/ImagePicker

Question

考慮在iPhone上使用6S斯威夫特3照片時，我發現了一個奇怪的問題。我試圖一個接一個地拍攝很多照片，最終導致應用程序崩潰。使用

下面的代碼：

import UIKit 

class WelcomeViewController : UIViewController, UINavigationControllerDelegate, UIImagePickerControllerDelegate 
{ 
    var imagePicker: UIImagePickerController! 
    var photoCount : Int = 0 
    @IBOutlet weak var photoCountLabel: UILabel! 
    @IBOutlet weak var memoryUseageLabel: UILabel! 

    @IBAction func TakePhotoAction(_ sender: Any) { 
     if (imagePicker == nil) 
     { 
      imagePicker = UIImagePickerController() 
      imagePicker.delegate = self 
      imagePicker.sourceType = .camera 
     } 

     present(imagePicker, animated: true, completion: nil) 
    } 

    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) { 
     imagePicker.dismiss(animated: true, completion: nil) 
     photoCount = photoCount + 1; 

     photoCountLabel.text = String(photoCount) 
    } 

    override func viewDidLoad(){ 
     super.viewDidLoad() 
     photoCount = 0; 

    } 
} 

我發現了一個應用程序崩潰和Xcode是說，它已「失去聯繫」與設備。 所以一切都指向一個內存泄漏和運行手段表明，它也提示有新的線程創建了個遍，他們從來沒有完成。

問題是，我使用的是非常基本的代碼，再利用機械手，駁回認爲，這是在整個應用程序的唯一視圖。

爲了讓事情更奇怪了，都當我與iOS 10.3.2

所以用我的iPhone 7在iOS 10.3.1，或在其他iPhone 6（不+）不會發生異常我把6+降級到了10.3.1，並再次得到了異常。我甚至放上了iOS 11 Beta，並且仍然發生異常。

我希望有人至少可以給我一些解釋，這是怎麼回事，或者爲什麼。

UPDATE

我在Xamarin遇到此窗體PCL項目，並決定把它全部出來，寫一個斯威夫特版本，看看問題是否依然發生與否。原來是這樣。無論如何，在測試Xamarin應用程序時，我們遇到了一個例外。

的異常被寫入日誌文件。這是內容：

Error Occurred: 
Objective-C exception thrown. Name: NSInvalidArgumentException Reason: *** setObjectForKey: object cannot be nil (key:   UIImagePickerControllerOriginalImage) 
Native stack trace: 
0 CoreFoundation      0x000000018a93eff8 <redacted> + 148 
1 libobjc.A.dylib      0x00000001893a0538 objc_exception_throw + 56 
2 CoreFoundation      0x000000018a822528 <redacted> + 0 
3 PhotoLibrary      0x0000000197b18980 <redacted> + 756 
4 PhotoLibrary      0x0000000197b1864c PLNotifyImagePickerOfImageAvailability + 28 
5 CameraUI       0x00000001a08e990c <redacted> + 456 
6 CameraUI       0x00000001a08e9218 <redacted> + 548 
7 UIKit        0x0000000190aa5010 <redacted> + 96 
8 UIKit        0x0000000190aa4f90 <redacted> + 80 
9 UIKit        0x0000000190a8f504 <redacted> + 440 
10 UIKit        0x0000000190aa4874 <redacted> + 576 
11 UIKit        0x0000000190aa4390 <redacted> + 2480 
12 UIKit        0x0000000190a9f728 <redacted> + 3192 
13 UIKit        0x0000000190a7033c <redacted> + 340 
14 UIKit        0x000000019126a014 <redacted> + 2400 
15 UIKit        0x0000000191264770 <redacted> + 4268 
16 UIKit        0x0000000191264a50 <redacted> + 5004 
17 UIKit        0x0000000191264a50 <redacted> + 5004 
18 UIKit        0x0000000191264b9c <redacted> + 148 
19 CoreFoundation      0x000000018a8ed42c <redacted> + 24 
20 CoreFoundation      0x000000018a8ecd04 <redacted> + 388 
21 CoreFoundation      0x000000018a8ea9a8 <redacted> + 744 
22 CoreFoundation      0x000000018a81ada4 CFRunLoopRunSpecific + 424 
23 GraphicsServices     0x000000018c284074 GSEventRunModal + 100 
24 UIKit        0x0000000190ad5058 UIApplicationMain + 208 
25 MyApp_iOS_beta      0x0000000100bcb634 wrapper_managed_to_native_UIKit_UIApplication_UIApplicationMain_int_string___intptr_intptr + 340 
26 MyApp_iOS_beta      0x000000010050c59c UIKit_UIApplication_Main_string___intptr_intptr + 44 
27 MyApp_iOS_beta      0x000000010050c45c UIKit_UIApplication_Main_string___string_string + 172 
28 MyApp_iOS_beta      0x0000000100078164 MyApp_iOS_Application_Main_string__ + 212 
29 MyApp_iOS_beta      0x00000001011f29f4 wrapper_runtime_invoke_object_runtime_invoke_dynamic_intptr_intptr_intptr_intptr + 244 
30 MyApp_iOS_beta      0x00000001038e504c mono_jit_runtime_invoke + 836 
31 MyApp_iOS_beta      0x000000010394f6b4 do_runtime_invoke + 112 
32 MyApp_iOS_beta      0x00000001039522dc do_exec_main_checked + 152 
33 MyApp_iOS_beta      0x00000001038cea44 mono_jit_exec + 268 
34 MyApp_iOS_beta      0x0000000103a02f70 xamarin_main + 2148 
35 MyApp_iOS_beta      0x00000001038a5e84 main + 96 
36 libdyld.dylib      0x000000018982959c <redacted> + 4 

Stack Trace: 
    at ObjCRuntime.Runtime.ThrowNSException (System.IntPtr ns_exception) [0x00000] in /Users/builder/data/lanes/4691/d2270eec/source/xamarin-macios/src/ObjCRuntime/Runtime.cs:319 
    at ObjCRuntime.Runtime.throw_ns_exception (System.IntPtr exc) [0x00000] in /Users/builder/data/lanes/4691/d2270eec/source/xamarin-macios/runtime/Delegates.generated.cs:126 
    at (wrapper native-to-managed) ObjCRuntime.Runtime:throw_ns_exception (intptr) 
--- End of stack trace from previous location where exception was thrown --- 
    at (wrapper managed-to-native) UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr) 
    at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Users/builder/data/lanes/4691/d2270eec/source/xamarin-macios/src/UIKit/UIApplication.cs:79 
    at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x00038] in /Users/builder/data/lanes/4691/d2270eec/source/xamarin-macios/src/UIKit/UIApplication.cs:63 
    at MyApp.iOS.Application.Main (System.String[] args) [0x00009] in /Users/MyApp/iOS/Main.cs:16 

Answer 1

var image: UIImage? = (info.value(forKey: UIImagePickerControllerOriginalImage) as? UIImage) 

使用該鍵從圖書館獲得原始圖片。在機iOS

這是Xamarin https://developer.xamarin.com/recipes/ios/media/video_and_photos/choose_a_photo_from_the_gallery/