Detected a case where constraints ambiguously suggest a height of zero

Question

After updating to Xcode 6.1 beta 2 when I run my app that contains tableview cells, the debug assistant says:

Warning once only: Detected a case where constr         


        

Answer 1

I have this issue on TableViewCells where the constraints are set on initialisation but where the cell's contents are loaded afterwards, this means the autolayout engine can't determine the height. The other solutions here don't work because I need the cell's height to be UITableView.automaticDimension.

I just added an extra constraint to the cell:

contentView.heightAnchor.constraint(equalToConstant: 44, priority: .defaultLow)

Answer 2

if you are extending your ViewController class with UITableView and also using navigation controller to show the screen then you dont need to perform segue with identifier this may cause an error of identifier ViewController, you can use pushViewController method to show the chat screen in order to get rid from this error so here is the code just paste it in to your UItableView delegate

let chatBox = ChatBoxViewController() navigationController?.pushViewController(chatBox, animated: true)

just put the name of your viewcontroller which you want to show next and yeah done.

Answer 3

I have same error, due to this line this error was shown.

self.layer.backgroundColor = UIColor(white: 1, alpha: 0.2) as! CGColor

I just change the line as following to fix the error

self.layer.backgroundColor = UIColor(white: 1, alpha: 0.2).cgColor

Answer 4

I got this warning today. Here is what made it disappear for me(in interface builder)

1.Set the row height field for the table view to something other than 44 2 Set the row height field for the tableView cell to something other than 44

I did not have to make any changes in code

Answer 5

I had the same error message, make sure all your outlets are valid like table view and tableview Constraints

Answer 6

I have also similar issue for custom tableview cell which has dynamic row height. Dynamic height wasn't reflected and got the same warning in console. The solution is Adding subviews to cell instead of contentView. BTW, I have created subviews programatically.