layer is a part of cycle in its layer tree iOS 9 Swift 2

Question

When I load my view controller I'm getting this error:

*** Terminating app due to uncaught exception 'CALayerInvalid', reason: 'layer <CALayer: 0x7fda42c66e30> is a part of cycle in its layer tree'

I don't know why. I think I might've added a third party framework that messed with layers, but I removed it in my troubleshooting. Any insights would be great.

EDIT

It happens during viewDidLoad of my tableViewcontroller. I have a tableView on my second vc. I've narrowed it down to it crashing on setting the heightForRowAtIndexPath on the 4th custom cell. The cell is on a static tableView................. :/ Getting closer!

Here's my heightForRowAtIndexPath:

override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
    
    print("idx = \(indexPath.row)")
    
    return super.tableView(tableView, heightForRowAtIndexPath: indexPath)
}

Pretty generic. Any thoughts on where else this might be caused?

score 55 · Answer 1 · answered Jun 19 '18 at 04:09

55

This might help someone still in trouble with this, For me the issue was this

layer.addSublayer(layer)

Adding a layer to itself ‍♂️ . After this mistake I am planning to kill myself :(.

answered Jun 19 '18 at 04:09

infiniteLoop

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Hahah did the same thing! – Michael Jun 28 '18 at 15:01
1

Haha, I think there is a queue of people that have done this! lol – RichAppz Jul 17 '18 at 12:20
Same thing here, your comment saved my life :) – Matej Ukmar Aug 13 '19 at 13:59
Ugh, I need to stop naming my test views `view` or remember to use `self.view` lol – froggomad Sep 05 '20 at 12:54
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Funny your nickname is `infiniteLoop` ) Thanks. – nikans Dec 11 '20 at 13:17
The same here! T_T – superpuccio Nov 23 '21 at 11:54
I did it because I have named my custom layer as 'lay' for testing and will never do it again, dang autocomplete haha. – Ahmed Shendy Jan 03 '22 at 06:23
Note to self: don't use `layer` as a variable name when creating new layers. – Raimundas Sakalauskas Nov 09 '22 at 10:43

score 31 · Answer 2 · answered Apr 10 '16 at 22:09

31

check if you add self.view in self.view, exemple:

self.view.addSubview(view)

or

contentView.addSubview(self.view)

answered Apr 10 '16 at 22:09

Pablo Ruan

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Thanks for saving me a ton a grief :thumbs_up: – Andrew Sowers Nov 02 '16 at 22:56
Good answer, but it doesn't tell you what to do instead. In the above case you probably mean to be adding a view other than the self.view as your subview. May be obvious to more experienced ios devs, but this clarification would have helped me aha – Jemar Jones Jan 26 '18 at 23:36
This was my issue too – devjme May 12 '23 at 18:03

score 21 · Accepted Answer · edited Aug 26 '19 at 06:36

21

I had the same error too and found this fix

It mentions to remove the accessoryView Outlet which you will see on the TableView.

To do this:

Click on the Table View
Go to the "Connections Inspector", it's the right window, the very last icon (looks like a circle with an arrow right)
Look for the accessoryView and disconnect the outlet

In the screenshot below, see the outlet you are to disconnect:

edited Aug 26 '19 at 06:36

Idee

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answered Sep 23 '15 at 14:05

exo_duz

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This is exactly what was causing my issue. I got it resolved. Thanks – Jun 22 '20 at 01:56

score 6 · Answer 4 · answered Jun 28 '18 at 05:51

One of my friend was facing the same issue. The root cause was lying in the viewForHeaderInSection delegate of UITableview.

He was adding a label in main view of the controller in this delegate. He was supposed to create a UIView and return it in this delegate but unfortunately he was returning self.view there. So removing this code fixed the issue.

score 2 · Answer 5 · answered Jul 22 '15 at 03:33

I've managed to fix it but not in the way that I'd hoped. I ended up scratching the tableViewCell that was causing the issue and rebuilding all the layout constraints from scratch. Not ideal, but it worked. I hope someone can come along in the future and explain why this error happened! Cheers.

score 1 · Answer 6 · answered Dec 08 '15 at 15:19

1

I solved one crash of this kind by removing the outlet to File' s owner in some of xib UI files. I answer here in case someone encounters a similar thing.

answered Dec 08 '15 at 15:19

xgdgsc

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score 0 · Answer 7 · answered Oct 27 '16 at 12:19

0

I had this issue too, and found out I accidentally created an outlet from the TableViewCell backgroundView to the TableView's view - DOH!

answered Oct 27 '16 at 12:19

jensk

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score 0 · Answer 8 · answered Sep 27 '20 at 22:39

0

Also, when saving view as a variable inside UIViewController don't give it the name "view" cause "view" is saved to the UIViewController's View

answered Sep 27 '20 at 22:39

Oz Shabat

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score 0 · Answer 9 · answered Jul 29 '21 at 09:15

For me the problem was
I created a cell created its class and made some IBOutlet after some time I realised that my project already have class for this cell. So, I deleted my class and assigned existing class to my cell but the forgot to break IBOutlet of the old class So, solution is:
just go to Connection Inspector and remove all broken IBOutlet

layer is a part of cycle in its layer tree iOS 9 Swift 2

EDIT

9 Answers9

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