Xcode6, iOS8 and (void)layoutSubviews

Question

I have custom UILabel which works fine on iOS6 and iOS7. But on iOS8 this label's (void)layoutSubviews method never get called. I create this label with initWithFrame, so this method should be called - and it's called on another iOS versions. What happens with autoLayout system in iOS8?

The issue is even worse, as also when using autolayout for the subview, it does not get layoutet. — fabb, Sep 23 '14 at 09:22
I created an example project showing the issue. Run on iOS 7 and 8 to see the difference. https://github.com/fabb/LabelTest — fabb, Sep 26 '14 at 13:59
I am also facing same issue. Did you get any answer on this? — ABC1, Sep 26 '14 at 21:14

score 5 · Answer 1 · answered Oct 02 '14 at 14:37

5

I just want to add this answer because the question title may lead a lot of ppl here with similar issues (like me).

With iOS 8 to 8.0.2 LayoutSubviews calls are unreliable. They may not be called ever or (in my case) are called in a loop.

Even though you should not do it, it was pretty safe to alloc stuff in LayoutSubviews, but with this buggy (?!) behaviour it can cause hard-to-trace bugs.

I don't know if 8.1 fixes all the issues but it will be some time until customer devices will run 8.1 and they do run 8.0.2 NOW

answered Oct 02 '14 at 14:37

NikkyD

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Am facing the same issue here. "LayoutSubviews" is called in a loop In order to cover users using iOS 8.0.2, Is there any Fix for this bug? – Saru Aug 06 '15 at 05:54
no, to my knowledge there is no fix. But you should not try to support versions of iOS that were in-between-versions. If someone still uses 8.0 or 8.0.2 they can upgrade to a newer version and fix the problem themselves. – NikkyD Aug 06 '15 at 12:41
Yeah that's true. But, unfortunately in apps, we can't ask every customer stucked on that version to upgrade their device. ;) Well, i think i have found a way around. Thanks for your reply. :) – Saru Aug 06 '15 at 14:02

Igor Palaguta · Answer 2 · 2014-09-11T05:05:10.650

I had same issue. Really layoutSubviews is not called anymore for UILabel on iOS8, as Apple does not expect anybody uses it as superview.

I am using ReactiveCocoaLayout, so it can be done by subscribing to rcl_frameSignal or rcl_boundsSignal.

-(void)awakeFromNib { [ self.rcl_boundsSignal subscribeNext: ^( NSValue* boundsValue ) { //layout changed } ]; }

Or you can use simple KVO to know when frame has been changed:

-(void)dealloc
{
   [ self removeObserver: self forKeyPath: @"layer.bounds" ];
}

-(void)observeValueForKeyPath:( NSString* )keyPath
                     ofObject:( id )object
                       change:( NSDictionary* )change
                      context:( void* )context
{
   if ( [ keyPath isEqualToString: @"layer.bounds" ] )
   {
      //layoutSubviews
   }
   else
   {
      [ super observeValueForKeyPath: keyPath
                      ofObject: object
                        change: change
                       context: context ];
   }
}

-(void)awakeFromNib
{
   [ self addObserver: self
           forKeyPath: @"layer.bounds"
              options: NSKeyValueObservingOptionNew
              context: 0 ];
}

Note that UIKit is per documentation **NOT** KVO-compliant - even if it works for some cases, it might break in the future. — fabb, Sep 23 '14 at 09:17

score 2 · Answer 3 · answered Oct 01 '14 at 09:25

2

The bug was fixed by Apple in iOS 8.1 (beta).

answered Oct 01 '14 at 09:25

fabb

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do you have a link or something to back that up ? – NikkyD Oct 01 '14 at 16:44
Can confirm, layoutSubview gets called again in 8.1 beta – amleszk Oct 01 '14 at 18:03
I have filed a Radar with Apple. And I have created a sample project: github.com/fabb/LabelTest – fabb Oct 02 '14 at 06:57

Xcode6, iOS8 and (void)layoutSubviews

3 Answers3

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