ios - 无法同时满足打开相机的约束

我有一个应用程序，它使用 webview 来显示一些 HTML 表单。在 HTML 表单中，添加了从设备中选择图像的功能。所有功能都来自用于捕获图像的 HTML 表单。当我从 webview 摄像头单击表单的浏览按钮时，一切正常，但我在 xcode 下登录。

Snapshotting a view that has not been rendered results in an empty snapshot. Ensure your view has been rendered at least once before snapshotting or snapshot after screen updates.
Unable to simultaneously satisfy constraints.
Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
    "<NSLayoutConstraint:0x16fa21f0 UIView:0x180afaa0.height == 0.454545*CAMModeDial:0x16f06760.height - 4.09091>",
    "<NSLayoutConstraint:0x18065020 CAMShutterButton:0x180bfbc0.centerY == CAMBottomBar:0x16f06100.centerY>",
    "<NSLayoutConstraint:0x18065b70 V:[CAMShutterButton:0x180bfbc0]-(0)-[CAMModeDial:0x16f06760]>",
    "<NSLayoutConstraint:0x18065ba0 CAMModeDial:0x16f06760.bottom == UIButton:0x180b5870'Cancel'.top>",
    "<NSLayoutConstraint:0x180645f0 V:[UIButton:0x180b5870'Cancel']-(31)-|   (Names: '|':CAMBottomBar:0x16f06100 )>",
    "<NSLayoutConstraint:0x180b6870 'UIView-Encapsulated-Layout-Height' V:[PLImagePickerCameraView:0x170f2600(0)]>",
    "<NSLayoutConstraint:0x180b8780 CAMBottomBar:0x16f06100.height == PLImagePickerCameraView:0x170f2600.height>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x16fa21f0 UIView:0x180afaa0.height == 0.454545*CAMModeDial:0x16f06760.height - 4.09091>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.

Unable to simultaneously satisfy constraints.
    Probably at least one of the constraints in the following list is one you don't want. Try this: (1) look at each constraint and try to figure out which you don't expect; (2) find the code that added the unwanted constraint or constraints and fix it. (Note: If you're seeing NSAutoresizingMaskLayoutConstraints that you don't understand, refer to the documentation for the UIView property translatesAutoresizingMaskIntoConstraints) 
(
    "<NSLayoutConstraint:0x18065020 CAMShutterButton:0x180bfbc0.centerY == CAMBottomBar:0x16f06100.centerY>",
    "<NSLayoutConstraint:0x18065b70 V:[CAMShutterButton:0x180bfbc0]-(0)-[CAMModeDial:0x16f06760]>",
    "<NSLayoutConstraint:0x18065ba0 CAMModeDial:0x16f06760.bottom == UIButton:0x180b5870'Cancel'.top>",
    "<NSLayoutConstraint:0x180645f0 V:[UIButton:0x180b5870'Cancel']-(31)-|   (Names: '|':CAMBottomBar:0x16f06100 )>",
    "<NSLayoutConstraint:0x180b6870 'UIView-Encapsulated-Layout-Height' V:[PLImagePickerCameraView:0x170f2600(0)]>",
    "<NSLayoutConstraint:0x180b8780 CAMBottomBar:0x16f06100.height == PLImagePickerCameraView:0x170f2600.height>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x18065b70 V:[CAMShutterButton:0x180bfbc0]-(0)-[CAMModeDial:0x16f06760]>

Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.

我无法解决它，谁能帮我理解这些错误并建议如何解决它们？

编辑 :- 在网上搜索 CAMShutterButton,CAMModeDial,CAMBottomBar,PLImagePickerCameraView 我发现 CAMShutterButton.h,CAMModeDial.h,CAMBottomBar.h> 是 CameraKit.framework 中的类文件，PLImagePickerCameraView.h 是 PhotoLibrary.framework 中的类文件。它们是 iOS 8 私有(private)框架的一部分，但我没有在我的应用程序中使用它们中的任何一个。

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Best Answer-推荐答案

改变约束的优先级

"<NSLayoutConstraint:0x18065b70 V:[CAMShutterButton:0x180bfbc0]-(0)-[CAMModeDial:0x16f06760]>" from Required(1000) to High(750)

关于ios - 无法同时满足打开相机的约束，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/27247695/