为什么我的应用程序在iOS 10上重复显示和使用UIImagePickerController时崩溃？

我们几年前开发的一款应用程序在iOS 10面世后开始崩溃。该应用程序反复显示UIImagePickerController，允许用户捕捉一个主题的多张照片。这样做40多次后，应用程序崩溃。这在我们测试过的所有设备上都是可复制的，但在引入iOS 10之前没有发生过。我们在Info.plist文件中有NSCameraUsageDescription和NSPhotoLibraryUsageDescription密钥

我已经创建了一个示例应用程序来演示这个问题。以下是最终导致崩溃的代码：

- (IBAction) cameraPressed:(id) sender {
    self.picker = [[UIImagePickerController alloc] init];
    self.picker.sourceType =  UIImagePickerControllerSourceTypeCamera;
    self.picker.delegate = self;
    self.picker.allowsEditing = NO;
    [self presentViewController:self.picker animated:YES completion:nil];
}

2016-11-04 20:30:11.884984 WLPBeta[2747:275474] [MC] Invalidating cache
2016-11-04 20:30:11.890776 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:30:13.017608 WLPBeta[2747:275091] [MC] Invalidating cache
2016-11-04 20:30:13.018312 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:30:19.271720 WLPBeta[2747:276311] [MC] Invalidating cache
2016-11-04 20:30:19.279462 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:08.229294 WLPBeta[2747:278515] [MC] Invalidating cache
2016-11-04 20:32:08.273941 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:09.335711 WLPBeta[2747:278514] [MC] Invalidating cache
2016-11-04 20:32:09.342161 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:14.193376 WLPBeta[2747:278515] [MC] Invalidating cache
2016-11-04 20:32:14.213902 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:47.944657 WLPBeta[2747:275091] [MC] Invalidating cache
2016-11-04 20:32:47.972053 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:48.550934 WLPBeta[2747:279485] [MC] Invalidating cache
2016-11-04 20:32:48.575065 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:50.855308 WLPBeta[2747:279485] [MC] Invalidating cache
2016-11-04 20:32:50.856329 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:52.201535 WLPBeta[2747:275091] [GatekeeperXPC] Connection to assetsd was interrupted or assetsd died

当用户重复使用连接到此iAction的摄影机按钮时，它最终开始减速（拾取程序的显示开始花费更长的时间），并最终崩溃（通常在使用摄影机50多次后）。不会生成崩溃日志，尽管连接到Xcode时，控制台中会出现如下输出，导致崩溃：

- (IBAction) cameraPressed:(id) sender {
    self.picker = [[UIImagePickerController alloc] init];
    self.picker.sourceType =  UIImagePickerControllerSourceTypeCamera;
    self.picker.delegate = self;
    self.picker.allowsEditing = NO;
    [self presentViewController:self.picker animated:YES completion:nil];
}

2016-11-04 20:30:11.884984 WLPBeta[2747:275474] [MC] Invalidating cache
2016-11-04 20:30:11.890776 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:30:13.017608 WLPBeta[2747:275091] [MC] Invalidating cache
2016-11-04 20:30:13.018312 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:30:19.271720 WLPBeta[2747:276311] [MC] Invalidating cache
2016-11-04 20:30:19.279462 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:08.229294 WLPBeta[2747:278515] [MC] Invalidating cache
2016-11-04 20:32:08.273941 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:09.335711 WLPBeta[2747:278514] [MC] Invalidating cache
2016-11-04 20:32:09.342161 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:14.193376 WLPBeta[2747:278515] [MC] Invalidating cache
2016-11-04 20:32:14.213902 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:47.944657 WLPBeta[2747:275091] [MC] Invalidating cache
2016-11-04 20:32:47.972053 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:48.550934 WLPBeta[2747:279485] [MC] Invalidating cache
2016-11-04 20:32:48.575065 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:50.855308 WLPBeta[2747:279485] [MC] Invalidating cache
2016-11-04 20:32:50.856329 WLPBeta[2747:273019] [MC] Reading from public effective user settings.
2016-11-04 20:32:52.201535 WLPBeta[2747:275091] [GatekeeperXPC] Connection to assetsd was interrupted or assetsd died

我还向苹果发布了一份bug报告，并将其添加到open radar：

有人遇到过这个问题吗？有没有一个修复程序可以让我们在不使用Xcode 8重新编译应用程序的情况下绕过这个问题？不幸的是，我们使用的第三方库尚未为Xcode 8和iOS 10 SDK做好准备，因此我们仍在使用Xcode 7.3.1构建应用程序

编辑：这里有一个指向Github回购的链接，其中包含一个示例应用程序，可用于演示该问题

编辑2:如果我更改代码以便在viewDidLoad中分配和初始化选择器，则在使用相机按钮的次数大致相同后，它仍会崩溃

- (void)viewDidLoad {
    [super viewDidLoad];
    self.picker = [[UIImagePickerController alloc] init];
    self.picker.sourceType =  UIImagePickerControllerSourceTypeCamera;
    self.picker.allowsEditing = NO;
}

- (IBAction) cameraPressed:(id) sender {
    [self presentViewController:self.picker animated:YES completion:nil];
}

试试这个代码

- (IBAction) cameraPressed:(id) sender {
   if (self.picker == nil){
      self.picker = [[UIImagePickerController alloc] init];
   }

    self.picker.sourceType =  UIImagePickerControllerSourceTypeCamera;
    self.picker.delegate = self;
    self.picker.allowsEditing = NO;
    [self presentViewController:self.picker animated:YES completion:nil];
}

---

您是否尝试在cameraPressed（）函数中声明Imagepicker变量

---

您的UIImagePickerController被定义为强

---

在销毁视图之前，请将其更改为“弱”或确保对象为“零”。

您需要明确关闭

UIImagePickerController

，即使它看起来是自动关闭的。如果没有，它可能会保留视图控制器，从而导致内存问题

从：

如果将图像选择器的ShowScameraControl属性设置为“否”，则 提供您自己的自定义控件，您可以拍摄多张照片 在关闭图像选择器界面之前。但是，如果你设置了 属性设置为“是”，则您的代理必须关闭图像选择器接口 用户拍摄一张照片或取消操作后

默认情况下，该属性为“是”，因此需要忽略

使用类似于以下内容的内容：

- (IBAction) cameraPressed:(id) sender {
    UIImagePickerController* picker = [[UIImagePickerController alloc] init];
    picker.sourceType =  UIImagePickerControllerSourceTypeCamera;
    picker.allowsEditing = NO;
    picker.delegate = self;
    [self presentViewController:picker animated:YES completion:nil];
}

- (void) imagePickerController:(UIImagePickerController *)picker
    didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info
{
    [self dismissViewControllerAnimated:YES completion:nil];
}

- (void) imagePickerControllerDidCancel:(UIImagePickerController *)picker
{
    [self dismissViewControllerAnimated:YES completion:nil];
}

-（iAction）摄像机显示：（id）发送方{
UIImagePickerController*picker=[[UIImagePickerController alloc]init]；
picker.sourceType=UIImagePickerController源类型摄像头；
picker.allowsdediting=否；
picker.delegate=self；
[自我呈现视图控制器：选择器已设置动画：是完成：无]；
}
-（无效）imagePickerController:（UIImagePickerController*）选择器
didFinishPickingMediaWithInfo:（NSDictionary*）信息
{
[自我解除视图控制器激活：是完成：无]；
}
-（无效）ImagePickerController IDCancel:（UIImagePickerController*）选择器
{
[自我解除视图控制器激活：是完成：无]；
}

您使用过仪器吗？可能您有内存泄漏或引用周期。我们有，但没有检测到任何泄漏或引用周期。如问题中所述，我将问题归结为一个简单的示例应用程序，只需在Xcode创建的框架项目中添加几行代码。我添加的代码如问题所示。是否有任何特殊原因使您必须在每次按下按钮时初始化imagePicker？为什么不将所有代码行移动到viewDidLoad，当按下按钮时，只触发presentViewController方法？没有特别的原因，但是如果我将选择器的初始化移动到viewDidLoad，在拍摄了大约相同数量的照片后，我仍然会遇到崩溃。您可能会遇到一个引用计数循环，将self.picker.delegate对象设置为其他对象（不是来自视图控制器的self），以避免ref-count循环问题。