Swift 向视图标签添加约束后，Xcode在生成中冻结

我正在构建一个简单的应用程序，并在代码中创建所有UI。该项目运行良好，直到我添加了一些标签的约束，并向情节提要中添加了一些内容（我发现情节提要对线框非常有用）

现在，当我尝试构建时，构建在编译Swift文件期间冻结（Xcode仍然响应输入）

在此之前（项目将要构建的时候），我的类是这样的：

class CurrentWeatherView: UIView {

    weak var tempLowLabel: UILabel! = UILabel()
    weak var tempLowIcon: UILabel! = UILabel()
    weak var tempHighLabel: UILabel! = UILabel()
    weak var tempHighIcon: UILabel! = UILabel()

    weak var precipChanceLabel: UILabel! = UILabel()
    weak var precipIconLabel: UILabel! = UILabel()
    weak var humidity: UILabel! = UILabel()
    weak var humidityIconLabel: UILabel! = UILabel()

    weak var icon: UILabel! = UILabel()
    weak var tempLabel: UILabel! = UILabel()

    weak var summaryLabel: UILabel! = UILabel()
    weak var summaryScroll: UIScrollView! = UIScrollView()
}

class CurrentWeatherView: UIView {

    weak var tempLowLabel: UILabel! = UILabel()
    weak var tempLowIcon: UILabel! = UILabel()
    weak var tempHighLabel: UILabel! = UILabel()
    weak var tempHighIcon: UILabel! = UILabel()

    weak var precipChanceLabel: UILabel! = UILabel()
    weak var precipIconLabel: UILabel! = UILabel()
    weak var humidityLabel: UILabel! = UILabel()
    weak var humidityIconLabel: UILabel! = UILabel()

    weak var icon: UILabel! = UILabel()
    weak var iconSummaryLabel: UILabel! = UILabel()
    weak var tempLabel: UILabel! = UILabel()

    weak var summaryLabel: UILabel! = UILabel()
    weak var summaryScroll: UIScrollView! = UIScrollView()

    func setUpLayout() {

        self.addSubview(tempLowLabel)
        self.addSubview(tempLowIcon)
        self.addSubview(tempHighLabel)
        self.addSubview(tempHighIcon)
        self.addSubview(precipChanceLabel)
        self.addSubview(precipIconLabel)
        self.addSubview(humidityLabel)
        self.addSubview(humidityIconLabel)
        self.addSubview(icon)
        self.addSubview(iconSummaryLabel)
        self.addSubview(tempLabel)
        self.addSubview(summaryLabel)
        self.addSubview(summaryScroll)

        tempLowLabel.translatesAutoResizingMaskToConstraints = false
        tempLowIcon.translatesAutoResizingMaskToConstraints = false
        tempHighLabel.translatesAutoResizingMaskToConstraints = false
        tempHighIcon.translatesAutoResizingMaskToConstraints = false
        precipChanceLabel.translatesAutoResizingMaskToConstraints = false
        precipIconLabel.translatesAutoResizingMaskToConstraints = false
        humidityLabel.translatesAutoResizingMaskToConstraints = false
        humidityIconLabel.translatesAutoResizingMaskToConstraints = false
        icon.translatesAutoResizingMaskToConstraints = false
        iconSummaryLabel.translatesAutoResizingMaskToConstraints = false
        tempLabel.translatesAutoResizingMaskToConstraints = false
        summaryLabel.translatesAutoResizingMaskToConstraints = false
        summaryScroll.translatesAutoResizingMaskToConstraints = false

        NSLayoutConstraint.activate([
                NSLayoutConstraint(item: tempHighIcon, attribute: .left, relatedBy: .equal, toItem: self, attribute: .left, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: tempHighIcon, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                tempHighIcon.heightAnchor.constraint(equalToConstant: 22),
                tempHighIcon.widthAnchor.constraint(equalToConstant: 16),

                NSLayoutConstraint(item: tempLowIcon, attribute: .left, relatedBy: .equal, toItem: self, attribute: .left, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: tempLowIcon, attribute: .top, relatedBy: .equal, toItem: tempHighIcon, attribute: .bottom, multiplier: 1.0, constant: 5),
                tempLowIcon.heightAnchor.constraint(equalToConstant: 22),
                tempLowIcon.widthAnchor.constraint(equalToConstant: 16),

                NSLayoutConstraint(item: tempHighLabel, attribute: .left, relatedBy: .equal, toItem: tempHighIcon, attribute: .right, multiplier: 1.0, constant: 8),
                NSLayoutConstraint(item: tempHighLabel, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                tempHighIcon.heightAnchor.constraint(equalToConstant: 22),
                tempHighIcon.widthAnchor.constraint(equalToConstant: 42),

                NSLayoutConstraint(item: tempLowLabel, attribute: .left, relatedBy: .equal, toItem: tempLowIcon, attribute: .right, multiplier: 1.0, constant: 8),
                NSLayoutConstraint(item: tempLowLabel, attribute: .top, relatedBy: .equal, toItem: tempHighLabel, attribute: .bottom, multiplier: 1.0, constant: 5),
                tempHighIcon.heightAnchor.constraint(equalToConstant: 22),
                tempHighIcon.widthAnchor.constraint(equalToConstant: 42),

                NSLayoutConstraint(item: icon, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                icon.centerXAnchor.constraint(equalTo: self.centerXAnchor),
                icon.widthAnchor.constraint(equalToConstant: 85),
                icon.heightAnchor.constraint(equalToConstant: 85),

                iconSummaryLabel.centerXAnchor.constraint(equalTo: icon.centerXAnchor),
                iconSummaryLabel.centerYAnchor.constraint(equalTo: icon.centerYAnchor),
                iconSummaryLabel.heightAnchor.constraint(equalToConstant: 75),
                iconSummaryLabel.widthAnchor.constraint(equalToConstant: 75),

                NSLayoutConstraint(item: tempLabel, attribute: .top, relatedBy: .equal, toItem: icon, attribute: .bottom, multiplier: 1.0, constant: 8),
                tempLabel.centerXAnchor.constraint(equalTo: self.centerXAnchor),
                tempLabel.widthAnchor.constraint(equalToConstant: 85),
                tempLabel.heightAnchor.constraint(equalToConstant: 25),

                NSLayoutConstraint(item: summaryScroll, attribute: .left, relatedBy: .equal, toItem: self, attribute: .left, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: summaryScroll, attribute: .right, relatedBy: .equal, toItem: self, attribute: .right, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: summaryScroll, attribute: .bottom, relatedBy: .equal, toItem: self, attribute: .bottom, multiplier: 1.0, constant: 8),
                summaryScroll.heightAnchor.constraint(equalToConstant: 21),
                summaryScroll.centerXAnchor.constraint(equalTo: self.centerXAnchor),

                NSLayoutConstraint(item: precipChanceLabel, attribute: .right, relatedBy: .equal, toItem: self, attribute: .right, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: precipChanceLabel, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                precipChanceLabel.heightAnchor.constraint(equalToConstant: 22),
                precipChanceLabel.widthAnchor.constraint(equalToConstant: 42),

                NSLayoutConstraint(item: humidityLabel, attribute: .right, relatedBy: .equal, toItem: self, attribute: .right, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: humidityLabel, attribute: .top, relatedBy: .equal, toItem: precipChanceLabel, attribute: .bottom, multiplier: 1.0, constant: 5),
                humidityLabel.heightAnchor.constraint(equalToConstant: 22),
                humidityLabel.widthAnchor.constraint(equalToConstant: 42),

                NSLayoutConstraint(item: precipIconLabel, attribute: .right, relatedBy: .equal, toItem: precipChanceLabel, attribute: .left, multiplier: 1.0, constant: 8),
                NSLayoutConstraint(item: precipIconLabel, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                precipIconLabel.heightAnchor.constraint(equalToConstant: 22),
                precipIconLabel.widthAnchor.constraint(equalToConstant: 16),

                NSLayoutConstraint(item: humidityIconLabel, attribute: .right, relatedBy: .equal, toItem: humidityLabel, attribute: .left, multiplier: 1.0, constant: 8),
                NSLayoutConstraint(item: humidityIconLabel, attribute: .top, relatedBy: .equal, toItem: precipIconLabel, attribute: .bottom, multiplier: 1.0, constant: 5),
                humidityIconLabel.heightAnchor.constraint(equalToConstant: 22),
                humidityIconLabel.widthAnchor.constraint(equalToConstant: 16),
            ])
    }
}

现在（当它无法构建时），它看起来是这样的：

class CurrentWeatherView: UIView {

    weak var tempLowLabel: UILabel! = UILabel()
    weak var tempLowIcon: UILabel! = UILabel()
    weak var tempHighLabel: UILabel! = UILabel()
    weak var tempHighIcon: UILabel! = UILabel()

    weak var precipChanceLabel: UILabel! = UILabel()
    weak var precipIconLabel: UILabel! = UILabel()
    weak var humidity: UILabel! = UILabel()
    weak var humidityIconLabel: UILabel! = UILabel()

    weak var icon: UILabel! = UILabel()
    weak var tempLabel: UILabel! = UILabel()

    weak var summaryLabel: UILabel! = UILabel()
    weak var summaryScroll: UIScrollView! = UIScrollView()
}

class CurrentWeatherView: UIView {

    weak var tempLowLabel: UILabel! = UILabel()
    weak var tempLowIcon: UILabel! = UILabel()
    weak var tempHighLabel: UILabel! = UILabel()
    weak var tempHighIcon: UILabel! = UILabel()

    weak var precipChanceLabel: UILabel! = UILabel()
    weak var precipIconLabel: UILabel! = UILabel()
    weak var humidityLabel: UILabel! = UILabel()
    weak var humidityIconLabel: UILabel! = UILabel()

    weak var icon: UILabel! = UILabel()
    weak var iconSummaryLabel: UILabel! = UILabel()
    weak var tempLabel: UILabel! = UILabel()

    weak var summaryLabel: UILabel! = UILabel()
    weak var summaryScroll: UIScrollView! = UIScrollView()

    func setUpLayout() {

        self.addSubview(tempLowLabel)
        self.addSubview(tempLowIcon)
        self.addSubview(tempHighLabel)
        self.addSubview(tempHighIcon)
        self.addSubview(precipChanceLabel)
        self.addSubview(precipIconLabel)
        self.addSubview(humidityLabel)
        self.addSubview(humidityIconLabel)
        self.addSubview(icon)
        self.addSubview(iconSummaryLabel)
        self.addSubview(tempLabel)
        self.addSubview(summaryLabel)
        self.addSubview(summaryScroll)

        tempLowLabel.translatesAutoResizingMaskToConstraints = false
        tempLowIcon.translatesAutoResizingMaskToConstraints = false
        tempHighLabel.translatesAutoResizingMaskToConstraints = false
        tempHighIcon.translatesAutoResizingMaskToConstraints = false
        precipChanceLabel.translatesAutoResizingMaskToConstraints = false
        precipIconLabel.translatesAutoResizingMaskToConstraints = false
        humidityLabel.translatesAutoResizingMaskToConstraints = false
        humidityIconLabel.translatesAutoResizingMaskToConstraints = false
        icon.translatesAutoResizingMaskToConstraints = false
        iconSummaryLabel.translatesAutoResizingMaskToConstraints = false
        tempLabel.translatesAutoResizingMaskToConstraints = false
        summaryLabel.translatesAutoResizingMaskToConstraints = false
        summaryScroll.translatesAutoResizingMaskToConstraints = false

        NSLayoutConstraint.activate([
                NSLayoutConstraint(item: tempHighIcon, attribute: .left, relatedBy: .equal, toItem: self, attribute: .left, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: tempHighIcon, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                tempHighIcon.heightAnchor.constraint(equalToConstant: 22),
                tempHighIcon.widthAnchor.constraint(equalToConstant: 16),

                NSLayoutConstraint(item: tempLowIcon, attribute: .left, relatedBy: .equal, toItem: self, attribute: .left, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: tempLowIcon, attribute: .top, relatedBy: .equal, toItem: tempHighIcon, attribute: .bottom, multiplier: 1.0, constant: 5),
                tempLowIcon.heightAnchor.constraint(equalToConstant: 22),
                tempLowIcon.widthAnchor.constraint(equalToConstant: 16),

                NSLayoutConstraint(item: tempHighLabel, attribute: .left, relatedBy: .equal, toItem: tempHighIcon, attribute: .right, multiplier: 1.0, constant: 8),
                NSLayoutConstraint(item: tempHighLabel, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                tempHighIcon.heightAnchor.constraint(equalToConstant: 22),
                tempHighIcon.widthAnchor.constraint(equalToConstant: 42),

                NSLayoutConstraint(item: tempLowLabel, attribute: .left, relatedBy: .equal, toItem: tempLowIcon, attribute: .right, multiplier: 1.0, constant: 8),
                NSLayoutConstraint(item: tempLowLabel, attribute: .top, relatedBy: .equal, toItem: tempHighLabel, attribute: .bottom, multiplier: 1.0, constant: 5),
                tempHighIcon.heightAnchor.constraint(equalToConstant: 22),
                tempHighIcon.widthAnchor.constraint(equalToConstant: 42),

                NSLayoutConstraint(item: icon, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                icon.centerXAnchor.constraint(equalTo: self.centerXAnchor),
                icon.widthAnchor.constraint(equalToConstant: 85),
                icon.heightAnchor.constraint(equalToConstant: 85),

                iconSummaryLabel.centerXAnchor.constraint(equalTo: icon.centerXAnchor),
                iconSummaryLabel.centerYAnchor.constraint(equalTo: icon.centerYAnchor),
                iconSummaryLabel.heightAnchor.constraint(equalToConstant: 75),
                iconSummaryLabel.widthAnchor.constraint(equalToConstant: 75),

                NSLayoutConstraint(item: tempLabel, attribute: .top, relatedBy: .equal, toItem: icon, attribute: .bottom, multiplier: 1.0, constant: 8),
                tempLabel.centerXAnchor.constraint(equalTo: self.centerXAnchor),
                tempLabel.widthAnchor.constraint(equalToConstant: 85),
                tempLabel.heightAnchor.constraint(equalToConstant: 25),

                NSLayoutConstraint(item: summaryScroll, attribute: .left, relatedBy: .equal, toItem: self, attribute: .left, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: summaryScroll, attribute: .right, relatedBy: .equal, toItem: self, attribute: .right, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: summaryScroll, attribute: .bottom, relatedBy: .equal, toItem: self, attribute: .bottom, multiplier: 1.0, constant: 8),
                summaryScroll.heightAnchor.constraint(equalToConstant: 21),
                summaryScroll.centerXAnchor.constraint(equalTo: self.centerXAnchor),

                NSLayoutConstraint(item: precipChanceLabel, attribute: .right, relatedBy: .equal, toItem: self, attribute: .right, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: precipChanceLabel, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                precipChanceLabel.heightAnchor.constraint(equalToConstant: 22),
                precipChanceLabel.widthAnchor.constraint(equalToConstant: 42),

                NSLayoutConstraint(item: humidityLabel, attribute: .right, relatedBy: .equal, toItem: self, attribute: .right, multiplier: 1.0, constant: 12),
                NSLayoutConstraint(item: humidityLabel, attribute: .top, relatedBy: .equal, toItem: precipChanceLabel, attribute: .bottom, multiplier: 1.0, constant: 5),
                humidityLabel.heightAnchor.constraint(equalToConstant: 22),
                humidityLabel.widthAnchor.constraint(equalToConstant: 42),

                NSLayoutConstraint(item: precipIconLabel, attribute: .right, relatedBy: .equal, toItem: precipChanceLabel, attribute: .left, multiplier: 1.0, constant: 8),
                NSLayoutConstraint(item: precipIconLabel, attribute: .top, relatedBy: .equal, toItem: self, attribute: .top, multiplier: 1.0, constant: 22),
                precipIconLabel.heightAnchor.constraint(equalToConstant: 22),
                precipIconLabel.widthAnchor.constraint(equalToConstant: 16),

                NSLayoutConstraint(item: humidityIconLabel, attribute: .right, relatedBy: .equal, toItem: humidityLabel, attribute: .left, multiplier: 1.0, constant: 8),
                NSLayoutConstraint(item: humidityIconLabel, attribute: .top, relatedBy: .equal, toItem: precipIconLabel, attribute: .bottom, multiplier: 1.0, constant: 5),
                humidityIconLabel.heightAnchor.constraint(equalToConstant: 22),
                humidityIconLabel.widthAnchor.constraint(equalToConstant: 16),
            ])
    }
}

所有这些限制对于Xcode来说都太多了吗

此外，索引也没有完成

---

我尝试过清理项目、清理构建文件夹、删除派生数据、重新启动我的机器、重新启动Xcode、更新Xcode并检查代码优化级别，但没有任何帮助。

我能够通过更新到Xcode 8.3 beta版来解决此问题。Xcode 8.3刚刚发布，所以应该也可以使用。

（1）当我看到“索引…”时，我学会了让Xcode单独使用。拿起一杯你最喜欢的饮料，在网上蹦蹦跳跳，小睡一会儿，随便什么。不要打断它。：-）（2） 我很好奇你为什么把你所有的UIKit变量都设置为弱。虽然这是IBOutlet的默认值，但我从来没有这样声明过我的方法-这并不意味着我的方法更正确，这只是一个主要的区别。@dfd我选择弱的原因有两个：1）IBOutlet是这样声明的，所以我认为这是你应该使用的方法。2） 我想这会有助于提高记忆力。你这样做有什么具体的原因吗？还有，什么是索引，我为什么不去处理它呢？这里的约束数量没有什么值得注意的。Xcode可以而且应该能够处理这一点（以及更多），我以我一直看到的方式编写代码——尽管我很少使用Obj-C，即使在那里也是如此。我没有比这更好的理由了。您声称Xcode在尝试构建时“冻结”——我不怀疑这一点，因此我正在研究可能存在的问题。至于索引，我记得在某处（可能在这里）看到一条评论，大意是“看到索引时，让Xcode做任何事情”。我已经让它发生在我身上了。。。我不明白为什么我无法构建，并尝试了从重新启动到拔下设备的所有操作，结果发现一切都不起作用。@dfd抱歉。我解释错了。身体冻结了。Xcode没有。请注意我对解释的编辑。>构建冻结（Xcode仍然响应输入）