UITabel在UITableHeaderView autoLayout中不适用于iPhone 6

Question

我在TableHeaderView中对UILabel使用autolayout。 UILabel的高度不固定，可能是单线或多线。我在ViewController中编写代码：

    override func viewDidLayoutSubviews() {
    super.viewDidLayoutSubviews()

    if let headerView = tableView.tableHeaderView {
        let height = headerView.systemLayoutSizeFittingSize(UILayoutFittingCompressedSize).height
        var headerFrame = headerView.frame

        if height != headerFrame.size.height {
            headerFrame.size.height = height
            headerView.frame = headerFrame
            tableView.tableHeaderView = headerView
        }
    }
}

它完全适用于iPhone 5.但是，在iPhone 6上，当UILabel是单行时，它就会消失。

这是错误日志

    2015-11-22 16:50:42.338 Basket[11898:996678] 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) 
(
    "<NSAutoresizingMaskLayoutConstraint:0x7f97840bd210 h=--& v=--& H:[UIView:0x7f9784072380(375)]>",
    "<NSAutoresizingMaskLayoutConstraint:0x7f97840bd2b0 h=--& v=--& V:[UIView:0x7f9784072380(363.5)]>",
    "<NSLayoutConstraint:0x7f9784032650 UIImageView:0x7f97840705a0.width == 1.33333*UIImageView:0x7f97840705a0.height>",
    "<NSLayoutConstraint:0x7f9784073a40 V:[UILabel:0x7f9784073e90'Funnybeer'(15)]>",
    "<NSLayoutConstraint:0x7f9784128b40 V:[UILabel:0x7f9784128940'Nino Mamaladze'(15)]>",
    "<NSLayoutConstraint:0x7f9784074d10 H:[UIImageView:0x7f97840705a0]-(0)-|   (Names: '|':UIView:0x7f9784072380 )>",
    "<NSLayoutConstraint:0x7f9784074d60 H:|-(0)-[UIImageView:0x7f97840705a0]   (Names: '|':UIView:0x7f9784072380 )>",
    "<NSLayoutConstraint:0x7f9784074e00 V:|-(0)-[UIImageView:0x7f97840705a0]   (Names: '|':UIView:0x7f9784072380 )>",
    "<NSLayoutConstraint:0x7f9784074f40 V:[UIImageView:0x7f97840705a0]-(0)-[UIView:0x7f9784073d20]>",
    "<NSLayoutConstraint:0x7f9784075080 V:[UIView:0x7f9784073d20]-(22)-[UILabel:0x7f9784073e90'Funnybeer']>",
    "<NSLayoutConstraint:0x7f9784075210 V:[UILabel:0x7f9784073e90'Funnybeer']-(3)-[UILabel:0x7f9784128940'Nino Mamaladze']>",
    "<NSLayoutConstraint:0x7f9784075260 V:[UILabel:0x7f9784074300'see you on friday :)']-(0)-|   (Names: '|':UIView:0x7f9784072380 )>",
    "<NSLayoutConstraint:0x7f9784075350 'summary top distance' V:[UILabel:0x7f9784128940'Nino Mamaladze']-(10)-[UILabel:0x7f9784074300'see you on friday :)']>",
    "<NSLayoutConstraint:0x7f9781cf59f0 'tool height' V:[UIView:0x7f9784073d20(44)]>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x7f9781cf59f0 'tool height' V:[UIView:0x7f9784073d20(44)]>

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.

我的故事板 有人可以帮帮我吗？

Answer 1

Marco Arment有great gist关于如何做到这一点。