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我UITableView在 Storyboard 中创建了一个，添加了所需的自动布局约束。我想在单击表格单元格时显示一个操作表，因此我编写了以下代码：

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
    tableView.deselectRow(at: indexPath, animated: false)
    let actionSheet = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet)
    actionSheet.addAction(UIAlertAction(title: "Play Video",  style: .default, handler: { (action) -> Void in
        // Play Video
    }))

    actionSheet.addAction(UIAlertAction(title: "Share", style: .default, handler: { (action) -> Void in
        // Share
    }))

    actionSheet.addAction(UIAlertAction(title: "Delete", style: .destructive, handler: { (action) -> Void in
        // Delete
    }))

    actionSheet.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: nil))
    self.present(actionSheet, animated: true, completion: nil)
}

Xcode 在构建时不会抱怨任何自动布局问题（没有警告/错误）。但是，当我运行应用程序并单击触发上述功能的表格单元格时，Xcode 控制台显示自动布局错误：

2019-07-18 15:35:03.472831+0800 MP4Convert[2797:357238] [LayoutConstraints] 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. 
(
    "<NSLayoutConstraint:0x2808bf8e0 UIView:0x104f16800.width == - 16   (active)>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x2808bf8e0 UIView:0x104f16800.width == - 16   (active)>

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

该值- 16永远不会出现在所有约束中。我尝试将标识符添加到现有约束中，但似乎NSLayoutConstraints上面提到的不存在。

我错过了什么？

UIViewController层次结构非常简单：

UIView > UITableView > UITableViewCell

在设备屏幕上显示时没有视觉上的不一致。

iPhone Xr 设备上的 Xcode 10.2.1、iOS 12.3.1

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