AutoLayout exceptions iOS6 - ios

I am currently using an xib with autolayout to create custom cells in collection view. I have different cell sizes for both orientation. Hence I change the width and height of the cell according to the orientation.
The problem is that when I change the device orientation I get huge number of warnings / exceptions in iOS6.
However when I do the same in iOS7 no warnings are there.
Though it's not affecting my functionality I would like to remove all these warnings.
Here is my XIB file
And following are the errors / warnings /exceptions I am getting.
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:0x164371f0 V:[UILabel:0x16437240(21)]>",
"<NSLayoutConstraint:0x16438050 V:[UILabel:0x16437240]-(1)-[UILabel:0x16437670]>",
"<NSLayoutConstraint:0x16437fd0 V:[UILabel:0x16437670]-(5)-| (Names: '|':LibraryCollectionViewCell:0x16436ae0 )>",
"<NSLayoutConstraint:0x16437f50 V:[UILabel:0x16436e10]-(0)-[UILabel:0x16437240]>",
"<NSLayoutConstraint:0x16437e90 V:|-(7)-[UILabel:0x16436e10] (Names: '|':LibraryCollectionViewCell:0x16436ae0 )>",
"<NSAutoresizingMaskLayoutConstraint:0x16354d00 h=--& v=--& V:[UICollectionView:0xb24f200(264)]>",
"<NSAutoresizingMaskLayoutConstraint:0x163513b0 h=-&- v=-&- LibraryCollectionViewCell:0x16436ae0.height == UICollectionView:0xb24f200.height - 264>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x164371f0 V:[UILabel:0x16437240(21)]>
Break on objc_exception_throw to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
I have tried [cell setTranslatesAutoresizingMaskIntoConstraints:NO] but it crashes the app instead.
Can anyone please provide some solution on this?

"<NSLayoutConstraint:0x164371f0 V:[UILabel:0x16437240(21)]>",
"<NSLayoutConstraint:0x16438050 V:[UILabel:0x16437240]-(1)-[UILabel:0x16437670]>",
"<NSLayoutConstraint:0x16437fd0 V:[UILabel:0x16437670]-(5)-| (Names: '|':LibraryCollectionViewCell:0x16436ae0 )>",
"<NSLayoutConstraint:0x16437f50 V:[UILabel:0x16436e10]-(0)-[UILabel:0x16437240]>",
"<NSLayoutConstraint:0x16437e90 V:|-(7)-[UILabel:0x16436e10] (Names: '|':LibraryCollectionViewCell:0x16436ae0 )>",
"<NSAutoresizingMaskLayoutConstraint:0x16354d00 h=--& v=--& V:[UICollectionView:0xb24f200(264)]>",
"<NSAutoresizingMaskLayoutConstraint:0x163513b0 h=-&- v=-&- LibraryCollectionViewCell:0x16436ae0.height == UICollectionView:0xb24f200.height - 264>"
OK, from your constraints you have...
(Numbers in brackets are last 3 digits of reference).
Label (240) with height constraint fixed to 21.
Label (240) with a vertical gap of 1 to label (670).
Label (670) with a vertical gap of 5 to the superview (ae0) bottom.
Label (e10) with a vertical gap of 7 to the superview (ae0) top.
UICollectionView (200) with fixed height of 264.
LibraryCollectionViewCell (ae0) with an equal height to the collection view - 264 (200).
< Adam Savage >OK! There's your problem!< / Adam Savage >
The last constraint in the list will give the cell a height of 0. (264 - 264 = 0)
However, in the cell you have a label with fixed height 21 and fixed vertical gaps of 7, 5 and 1.
264 - 264 = 0
21 + 7 + 5 + 1 = 36
36 != 0
You can fix this a number of ways. Remove the constraint between the cell and the collection view. Remove the fixed height constraint on the label. etc...
I'd recommend drawing out how you want it to work (on paper) and scribbling in the constraints that you need. Or put a picture of what you are trying to do into your question so we can try to help.

A lot has changed in the way Auto layout takes place from iOS 6.0 to iOS 7.0.
This is quite evident from auto layout implementation via X-Code 4.x & X-Code 5.x.
Since Apple is now expecting apps to be built in X-Code 5.x, I would suggest to go with the same.
Check for the base SDK as well.

Related

UIView height not adjusting to subview heights in UITableView header

I have a UITableView with a header view and a custom row. The header view height is not adjusting properly to the constrained heights of its subviews.
The header view container view has the following subviews with constrained heights:
View (this height should compute to 188 but is 128 instead)
Map: UIImage (height = 128)
View: UIView (height = 60)
The header view height should be computed at Map Height + View Height = 128 + 60 = 188 as shown in Storyboard. However running this in the simulator squishes the header view to 128 like this:
Further inspection shows the header view height is 128 and not 188 as expected:
Also the Debug area shows a constraint conflict which shows the header view height is trying to be 128 which conflicts with the heights of its subviews. As a result it squishes the map height:
2015-11-27 16:58:46.415 MyApp[3387:52799] 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:0x7fcb5acf1270 h=--& v=--& V:[UIView:0x7fcb5c246620(128)]>",
"<NSLayoutConstraint:0x7fcb5c24c440 V:[Stop Details Container]-(0)-| (Names: Stop Details Container:0x7fcb5c24c490, '|':UIView:0x7fcb5c246620 )>",
"<NSLayoutConstraint:0x7fcb5c24c6f0 V:[Map]-(0)-[Stop Details Container] (Names: Stop Details Container:0x7fcb5c24c490, Map:0x7fcb5c24aa10 )>",
"<NSLayoutConstraint:0x7fcb5c24c830 V:|-(0)-[Map] (Names: Map:0x7fcb5c24aa10, '|':UIView:0x7fcb5c246620 )>",
"<NSLayoutConstraint:0x7fcb5c24c880 V:[Map(128)] (Names: Map:0x7fcb5c24aa10 )>",
"<NSLayoutConstraint:0x7fcb5c24c8d0 V:[Stop Details Container(60)] (Names: Stop Details Container:0x7fcb5c24c490 )>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x7fcb5c24c880 V:[Map(128)] (Names: Map:0x7fcb5c24aa10 )>
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.
How can I have the header view height properly compute to the heights of its subviews?
In order to force the height of the tableViewHeader I had to manually edit the height property in my Storyboard file with a text editor and this did the trick.
This is most certainly a bug in Xcode 7.1.

UITableViewAutomaticDimension not working properly in iOS 9

In my app I have custom tableViewCells with a fixed ratio (16x9). To achieve that, I placed a view in the cell, fixed it to its parent view (although I did it in interface builder: V/H:|-[innerView]-|).
Also, I put a ratio constraint on it.
In my tableViewController I'm using UITableViewAutomaticDimension as a table cell height.
The estimated row height is 180, wich is the exact size the cell will have on a 320px wide display (as I, as you can see, do).
I'm still deploying for 8.4, but when running the project on an Device with iOS 9, I'm getting tons of auto layout warnings, although everything works fine and looks perfect.
The warning itself is absolutely right. There are two constraints I don't want – these that iOS added on its own.
2015-09-29 11:24:57.771 app[1039:324736] 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:0x147d3e0d0 UIView:0x14901ff70.height == 0.5625*UIView:0x14901ff70.width>",
"<NSLayoutConstraint:0x147dd0210 H:|-(0)-[UIView:0x14901ff70] (Names: '|':UITableViewCellContentView:0x14901f960 )>",
"<NSLayoutConstraint:0x147deeca0 V:|-(0)-[UIView:0x14901ff70] (Names: '|':UITableViewCellContentView:0x14901f960 )>",
"<NSLayoutConstraint:0x149053c30 V:[UIView:0x14901ff70]-(0)-| (Names: '|':UITableViewCellContentView:0x14901f960 )>",
"<NSLayoutConstraint:0x147dbc2b0 H:[UIView:0x14901ff70]-(0)-| (Names: '|':UITableViewCellContentView:0x14901f960 )>",
"<NSLayoutConstraint:0x149070800 'UIView-Encapsulated-Layout-Height' V:[UITableViewCellContentView:0x14901f960(179.5)]>",
"<NSLayoutConstraint:0x1490707b0 'UIView-Encapsulated-Layout-Width' H:[UITableViewCellContentView:0x14901f960(320)]>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x147d3e0d0 UIView:0x14901ff70.height == 0.5625*UIView:0x14901ff70.width>
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.
The only thing I see here are the missing 0.5 pixels that iOS subtracted somehow magically.
The issue is the two constraints that the tableview adds automatically. UIView-Encapsulated-Layout-Height and width are probably the height and width the table view calculated for the cell during the initial load, based on the cell's constraints at that time.
"<NSLayoutConstraint:0x149070800 'UIView-Encapsulated-Layout-Height' V:[UITableViewCellContentView:0x14901f960(179.5)]>",
"<NSLayoutConstraint:0x1490707b0 'UIView-Encapsulated-Layout-Width' H:[UITableViewCellContentView:0x14901f960(320)]>"
As the priorities for these constraints are 1000 what you can do is lower your height and width constraint priorities and let the encapsulated size to be applied when needed (at load).
Seems you have added two ratio constraints added on two different views.
One that should be there is,
<NSLayoutConstraint:0x14d939e00 UIView:0x14da107f0.width ==
1.77778*UIView:0x14da107f0.height>
has memory address 0x14d939e00 added on UIView with address 0x14da107f0.
The other one is breaking.
<NSLayoutConstraint:0x14c5eae90 UIView:0x14c5ead30.height ==
0.5625*UIView:0x14c5ead30.width>
This one is added on a UIView (0x14c5ead30). Look for this view and remove this ratio constraint.

Contraints greyed-out in Xcode

I am trying to debug+understand autolayout constraints and I notice that when debugging the view with xcode (using the cool layer thing) I noticed that on one element in the view the constraints look like this
and the view is indeed ignoring these constraints.
All constraints have the same priority (1000) since I want them all. All constraints were made with interface builder and not through code, and there are not warning or conflicts in IB.
But in runtime I do see this
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:0x79684f10 V:[UIImageView:0x79686800(>=160)]>",
"<NSLayoutConstraint:0x7968a310 V:[UIImageView:0x79686800]-(130.5)-| (Names: '|':UIView:0x79686790 )>",
"<NSLayoutConstraint:0x7968a340 V:|-(0)-[UIImageView:0x79686800] (Names: '|':UIView:0x79686790 )>",
"<NSLayoutConstraint:0x796997b0 'UIView-Encapsulated-Layout-Height' V:[CoverCell:0x79686570(192)]>",
"<NSAutoresizingMaskLayoutConstraint:0x7969cd30 h=-&- v=-&- UIView:0x79686790.height == CoverCell:0x79686570.height>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x79684f10 V:[UIImageView:0x79686800(>=160)]>
So from this I understand that some rules conflict, but I'm not sure how to read this
the >=160 is a rule on the UIImageView so it would have height of atleast 160 and 130.5 is the bottom padding of the imageview (so when using systemLayoutSizeFittingSize:UILayoutFittingCompressedSize the height won't be 0. So the minimum height for the entire cell is 160+130.5)
The rest of the error I don't understand.
What is wrong with the constraints and why do constraint conflicts occur in runtime and not in IB?
XCode 6 now supports different layouts. This greyed out constraints exist in Compact Width | Any Height layout, for example, but you currently editing Any Width | Any Height.
More detailed:
Storyboard View Elements Greyed Out
It depends. If you don't use size classes the grey ones are the removed ones. And you need to remove them second time. No matter how stupid it sounds.
If you use size classes, it means that your current size class is different than for greyed constraint. (however the first scenario is also possible...)
In your case it looks like this is the first case. You need to remove greyed constraints once again.

Autolayout is complaining about leading/trailing space for UIImageView

I have a UICollectionViewCell in storyboard that has a UIImageView inside of it.
The UICollectionViewCell size is width: 189, height: 239 . The ImageView has the following constraints:
Trailing Space to cell = 31
Leading Space to cell = 31
Bottom Space to cell = 25
Top Space to cell = 31
I receive the following error when running:
2014-11-28 19:53:33.934 AppName[1585:35698] 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:0x7fa4a0d75220 H:[UIImageView:0x7fa4a0d743e0]-(31)-| (Names: '|':UIView:0x7fa4a0d73d40 )>",
"<NSLayoutConstraint:0x7fa4a0d752c0 H:|-(32)-[UIImageView:0x7fa4a0d743e0] (Names: '|':UIView:0x7fa4a0d73d40 )>",
"<NSAutoresizingMaskLayoutConstraint:0x7fa4a0d567a0 h=--& v=--& H:[UIView:0x7fa4a0d73d40(50)]>" )
Will attempt to recover by breaking constraint
NSLayoutConstraint:0x7fa4a0d75220
H:[UIImageView:0x7fa4a0d743e0]-(31)-| (Names:
'|':UIView:0x7fa4a0d73d40 )>
Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints
to catch this in the debugger. The methods in the
UIConstraintBasedLayoutDebugging category on UIView listed in
may also be helpful.
I tried changing the leading/trailing values in all kinds of ways (tried even/odd numbers) with no success. What is causing this?
This is a known bug in iOS 8 (see this post, Autoresizing issue of UICollectionViewCell contentView's frame in Storyboard prototype cell (Xcode 6, iOS 8 SDK) happens when running on iOS 7 only). The cell is the correct size that you set in the storyboard, but the cell's content view's size is staying at 50x50, which is why you get the constraint error. It can be fixed by adding this line after you create the cell in cellForItemAtIndexPath:,
cell.contentView.frame = cell.bounds

Unable to simultaneously satisfy constraints - No constraints in place

I have gone through and removed every single user constraint yet I am still getting the following error ONLY after I rotate the device. I have absolutely no clue why though. Does anyone have any ideas?
2013-01-14 21:30:31.363 myApp[35869:c07] 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:0x84543d0 h=--& v=--& V:[UIView:0xa330270(768)]>",
"<NSLayoutConstraint:0xa338350 V:[UIView:0xa331260]-(-1)-| (Names: '|':UIView:0xa330270 )>",
"<NSLayoutConstraint:0xa338390 V:|-(841)-[UIView:0xa331260] (Names: '|':UIView:0xa330270 )>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0xa338350 V:[UIView:0xa331260]-(-1)-| (Names: '|':UIView:0xa330270 )>
Break on objc_exception_throw to catch this in the debugger.
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKit/UIView.h> may also be helpful.
Let's look at these one by one.
"<NSAutoresizingMaskLayoutConstraint:0x84543d0 h=--& v=--& V:[UIView:0xa330270(768)]>"
This is saying view 0xa330270 (A) must be 768 points high.
"<NSLayoutConstraint:0xa338350 V:[UIView:0xa331260]-(-1)-| (Names: '|':UIView:0xa330270 )>"
This is saying view 0xa331260 (B)'s bottom edge must be a gap of -1 from the bottom of A, which is it's superview.
"<NSLayoutConstraint:0xa338390 V:|-(841)-[UIView:0xa331260] (Names: '|':UIView:0xa330270 )>"
This is saying that B's top edge must be a gap of 841 points from the top of its superview, A.
These three things can't all be true - A can't be 768 points high, and contain a subview with a top edge 841 points inset from the top and -1 points inset from the bottom. Where have you defined each of these constraints?
You haven't said what layout you are trying to achieve, but it looks like you might have an autoresizing mask on the superview that is preventing it changing in height when you rotate the device. As far as I know the autoresizing constraints only appear if you have added views programmatically, since a storyboard or xib is either all-autolayout, or not. Unless you are doing something like adding an auto laid out view (loaded from a nib?) to another view from a non-autolayout nib?
Its worth knowing the basics, and understand what Apple/Xcode is trying to tell you through the logs
H = Horizontal constraint(for leading and Trailing)
V = Vertical constraint(top and bottom edge)
h = height
w = width
TopEdge -> V:|-(points)-[VIEW:memoryAddress]
BottomEdge -> V:[VIEW:memoryAddress]-(points)-|
Leading -> H:|-(points)-[VIEW:memoryAddress]
Trailing -> H:[VIEW:memoryAddress] -(points)-|
height -> h= --& v=--& V:[VIEW:memoryAddress((points)]
width -> VIEW:memoryAddress.width == points
between -> H:[VIEW 1]-(51)-[VIEW 2]
Once you understand this, reading your specific error is pretty easy
thanks to http://useYourLoaf.com for this complete solution:
http://useyourloaf.com/blog/using-identifiers-to-debug-autolayout.html
A quick tip I found buried in a WWDC 2015 session on Auto Layout that helps when debugging problems with constraints
If you have used Auto Layout you will be familiar with the log that Xcode spits out when you get something wrong. To create an example I modified my Stack View sample code and added a constraint to each of the images to give them a fixed width of 240 (not a good idea as we will see).
That works in regular width views such as the iPad but is too wide for a compact width view such as the iPhone in portrait. The console log at runtime is not fun to read. Skipping the boilerplate text you get a list of the problematic constraints:
"<NSLayoutConstraint:0x7fc1ab520360 H:[UIImageView:0x7fc1ab532650(240)]>",
"<NSLayoutConstraint:0x7fc1ab536ef0 H:[UIImageView:0x7fc1ab537380(240)]>",
"<NSLayoutConstraint:0x7fc1ab545cc0 UIView:0x7fc1ab53d870.trailingMargin == UIStackView:0x7fc1ab53dae0.trailing>",
"<NSLayoutConstraint:0x7fc1ab545d10 UIStackView:0x7fc1ab53dae0.leading == UIView:0x7fc1ab53d870.leadingMargin>",
"<NSLayoutConstraint:0x7fc1ab54e240 'UISV-alignment' UIStackView:0x7fc1ab53dc70.centerX == UIStackView:0x7fc1ab531a10.centerX>",
"<NSLayoutConstraint:0x7fc1ab5167c0 'UISV-canvas-connection' UIStackView:0x7fc1ab531a10.leading == UIImageView:0x7fc1ab532650.leading>",
"<NSLayoutConstraint:0x7fc1ab54ad80 'UISV-canvas-connection' H:[UIImageView:0x7fc1ab537380]-(0)-| (Names: '|':UIStackView:0x7fc1ab531a10 )>",
"<NSLayoutConstraint:0x7fc1ab5397d0 'UISV-canvas-connection' UIStackView:0x7fc1ab53dae0.leading == _UILayoutSpacer:0x7fc1ab54c3c0'UISV-alignment-spanner'.leading>",
"<NSLayoutConstraint:0x7fc1ab54a4a0 'UISV-canvas-connection' UIStackView:0x7fc1ab53dae0.centerX == UIStackView:0x7fc1ab53dc70.centerX>",
"<NSLayoutConstraint:0x7fc1ab54b110 'UISV-spacing' H:[UIImageView:0x7fc1ab532650]-(16)-[UIImageView:0x7fc1ab537380]>",
"<NSLayoutConstraint:0x7fc1ab548210 'UISV-spanning-boundary' _UILayoutSpacer:0x7fc1ab54c3c0'UISV-alignment-spanner'.leading <= UIStackView:0x7fc1ab531a10.leading>",
"<NSLayoutConstraint:0x7fc1ab551690 'UIView-Encapsulated-Layout-Width' H:[UIView:0x7fc1ab53d870(375)]>"
The log then tells you which of the above constraints it has decided to break:
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x7fc1ab536ef0 H:[UIImageView:0x7fc1ab537380(240)]>
The log output uses the auto layout visual format language but it is hard to pick out my constraints from those created by the system. This is especially the case with stack views which are by design intended to create most of the constraints for you. In this trivial example I know the fixed width constraints that I just added broke things but it is hard to see that from the log and the more complex the view the harder it gets.
Adding an Identifier to a Constraint
The log gets a lot easier to understand if you add an identifier to each constraint (NSLayoutConstraint has had an identifier property since iOS 7). In Interface Builder find the constraint and add the identifier in the Attributes inspector (I am using $ as a prefix/suffix to make them stand out in the log):
Update 18-August-2015: As pointed out in the comments the identifier can only be edited in Interface Builder starting with Xcode 7. It is not visible in Xcode 6.4.
If adding the constraint in code:
constraint.identifier = "$HeartImageFixedWidth$"
It is trickier if you are using the visual format language which uses arrays of constraints. For example, consider the Swift code fragment to create a fixed width constraint for the heart image view:
let heartWidth = NSLayoutConstraint.constraintsWithVisualFormat("[heart(240)]",
options:[], metrics:nil, views:viewsDictionary)
Since heartWidth is an array of type [NSLayoutConstraint] setting the identifier is a little more work:
for constraint in heartWidth {
constraint.identifier = "$HeartImageFixedWidth$"
}
heartImage.addConstraints(heartWidth)
With identifies set for my constraints it is now much easier to find them in the log file (see the first four lines):
"<NSLayoutConstraint:0x7f92a305aeb0 '$ContainerStackViewLeading$' UIStackView:0x7f92a3053220.leading == UIView:0x7f92a3052fb0.leadingMargin + 32>",
"<NSLayoutConstraint:0x7f92a305b340 '$ContainerStackViewTrailing$' UIView:0x7f92a3052fb0.trailingMargin == UIStackView:0x7f92a3053220.trailing + 32>",
"<NSLayoutConstraint:0x7f92a301cf20 '$HeartImageFixedWidth$' H:[UIImageView:0x7f92a3047ef0(240)]>",
"<NSLayoutConstraint:0x7f92a3009be0 '$StarImageFixedWidth$' H:[UIImageView:0x7f92a304d190(240)]>",
"<NSLayoutConstraint:0x7f92a3060cc0 'UISV-alignment' UIStackView:0x7f92a30533b0.centerX == UIStackView:0x7f92a30472b0.centerX>",
"<NSLayoutConstraint:0x7f92a301c590 'UISV-canvas-connection' UIStackView:0x7f92a30472b0.leading == UIImageView:0x7f92a3047ef0.leading>",
"<NSLayoutConstraint:0x7f92a305f680 'UISV-canvas-connection' H:[UIImageView:0x7f92a304d190]-(0)-| (Names: '|':UIStackView:0x7f92a30472b0 )>",
"<NSLayoutConstraint:0x7f92a3064190 'UISV-canvas-connection' UIStackView:0x7f92a3053220.leading == _UILayoutSpacer:0x7f92a30608a0'UISV-alignment-spanner'.leading>",
"<NSLayoutConstraint:0x7f92a30415d0 'UISV-canvas-connection' UIStackView:0x7f92a3053220.centerX == UIStackView:0x7f92a30533b0.centerX>",
"<NSLayoutConstraint:0x7f92a305fa10 'UISV-spacing' H:[UIImageView:0x7f92a3047ef0]-(16)-[UIImageView:0x7f92a304d190]>",
"<NSLayoutConstraint:0x7f92a30508c0 'UISV-spanning-boundary' _UILayoutSpacer:0x7f92a30608a0'UISV-alignment-spanner'.leading <= UIStackView:0x7f92a30472b0.leading>",
"<NSLayoutConstraint:0x7f92a3063240 'UIView-Encapsulated-Layout-Width' H:[UIView:0x7f92a3052fb0(375)]>"
It also much clearer which of the constraints the system has chosen to break:
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x7f92a3009be0 '$StarImageFixedWidth$' H:[UIImageView:0x7f92a304d190(240)]>
Adding identifiers to constraints is not without effort but it can pay off the next time you have to sort through the debug log of a complex layout.
Further Reading
WWDC 2015 Session 219 Mysteries of Auto Layout, Part 2
I guess this is not a common error, but I solved it somewhat in a layman way. I was getting cryptic messages like the one above. To make sense of it, I created dummy view classes and attached it to the views in my storyboard. For example, if I had a UIView, I created a class called AddressView and attached it to this view in story board. Its a bit time consuming, but it worked for me. After that instead of object-ids, I got class names which helped me zero in on the views that were causing the issue very easily. My error message now read,
2013-07-02 04:16:20.434 Myproject [2908:c07] 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:0x9edeae0 V:|-(0)-[AddressView:0x143ee020] (Names: '|':MainView:0x129eb6a0 )>",
"<NSAutoresizingMaskLayoutConstraint:0x11e998c0 h=--& v=--& V:[MainView:0x129eb6a0(704)]>",
"<NSLayoutConstraint:0x156720b0 V:[AddressView:0x143ee020]-(896)-| (Names: '|':MainView:0x129eb6a0 )>"
)
Here you can see, the names of my views MainView and Address view are causing the issue.
To resolve it, I just moved my subview (in this case Address view) and repositioned it back. I think the issue began as I was using a mix of new Automatic Layour in Xcode 4.5 and old skills or manually positioning the views.
Anyways, not sure if it was more luck than diligence, but nevertheless this could be a different way of debugging. Maybe this helps someone!
YourConstraintView.translatesAutoresizingMaskIntoConstraints = NO;
Did it for me.
I've fixed this problem be deleting all translatesAutoresizingMaskIntoConstraints properties from xib file (Open xib as a source code).
One note. You get this error in logs if you are testing using a personal hotspot connection, and the hotspot status bar is at the top. It throws off the constraints.
Hope this helps someone.. was driving me nuts.
For me this error was spitted when I gave tableView.estimatedRowHeight = UITableViewAutomaticDimension
This should have been tableView.estimatedRowHeight = "Some hardcoded value"
I had this problem and took me 2 days to figure out the source of the problem....
If you open a storyboard programmatically in you code just make sure you do it like this:
UIStoryboard *story = [UIStoryboard storyboardWithName:#"MovieMaker" bundle:nil];
UIViewController *vc = [story instantiateInitialViewController];
//this causes layout to break [self presentViewController:vc animated:YES completion:nil];
[self showViewController:vc sender:nil];
I was using the commented line (using presentViewController) and the orientation bug has happening throwing constraints conflicts that weren't my constraints... changing to showViewController all constraints conflicts were gone and orientation works...... (I don't really know why it works with show and not present... still thinking it's... ALIENS...)
This issue of the generated message "Unable to simultaneously satisfy contraints" in the debug console, is also experienced in XCode 9.4.
In my particular instance on the iPad simulator, the message would generate:
1) Only when placing the focus on a particular UITextField.
2) Even with all view contraints removed.
2) Even with all view contraints "Reset to Suggested Contraints".
However, when the software keyboard was toggled on to display, the message would not be generated.
Therefore, how much time should I spend on this issue, that in my instance is only generated when the software keyboard is toggled off.
this line solved my problem when logs like above in uitableviewCell
func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
return UITableView.automaticDimension > CellHeight.rowHeight44 ? UITableView.automaticDimension : CellHeight.rowHeight44
}

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