Question

[IOS 7.0] 我有自定义UITableViewCell并使用systemlayoutsizefittingsize:来获取heightForRowAtIndexPath中的高度，但它给了我这些警告，高度返回为0.所以什么我的约束错了吗？

PS：如果我使用修复高度（假设说200px），则约束有效

PPS：我使用[cell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize]

PPPS：当我使用"<NSLayoutConstraint:0x7feafaa4df50 UITableViewCellContentView:0x7feafaa3c0b0.height == 0.5>"

时，会自动添加此约束[cell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize]

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:0x7feafaa3f570 UILabel:0x7feafaa3f7d0.height == 18>",
    "<NSLayoutConstraint:0x7feafaa40540 UILabel:0x7feafaa407e0.height == 25>",
    "<NSLayoutConstraint:0x7feafaa42010 UILabel:0x7feafaa3f210.top == UITableViewCellContentView:0x7feafaa3c0b0.top + 18>",
    "<NSLayoutConstraint:0x7feafaa421a0 UILabel:0x7feafaa3f7d0.top == UILabel:0x7feafaa3f210.bottom + 4>",
    "<NSLayoutConstraint:0x7feafaa422e0 GCTLabelEllipsis:0x7feafaa3fd70.top == UILabel:0x7feafaa3f7d0.bottom - 2>",
    "<NSLayoutConstraint:0x7feafaa42380 UITableViewCellContentView:0x7feafaa3c0b0.bottom == UILabel:0x7feafaa407e0.bottom + 16>",
    "<NSLayoutConstraint:0x7feafaa423d0 UILabel:0x7feafaa407e0.top == GCTLabelEllipsis:0x7feafaa3fd70.bottom + 8>",
    "<NSLayoutConstraint:0x7feafaa4df50 UITableViewCellContentView:0x7feafaa3c0b0.height == 0.5>"
)

Will attempt to recover by breaking constraint 
<NSLayoutConstraint:0x7feafaa40540 UILabel:0x7feafaa407e0.height == 25>

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.

修改

这是我的布局（它们在contentView下属于同一级别）

|-------------------------------------------------------------------------------------------|
|                                           | 18                                            |
| -- 12 -- UIImageView (w 20) -- 12 --  UILabel - 0 lines word warp -- 6 -- UIlabel -- 8 -- |
|                                           | 4                                             |
|                                       UILabel - 1 lines trailing, h = 18                  |
|                                           | -2                                            |
|                                       GCTLabelEllipsis (UILabel) - 0 line word warp       |
|                                           | 8                                             |
|                                       UILabel - 1 line trailing, h = 25                   |
|                                           | 16                                            |
--------------------------------------------------------------------------------------------|

UITableViewCell systemlayoutsizefittingsize返回0高度并给出约束警告

0 个答案: