XLPagerTabStrip crashing when self.view.layoutIfNeeded() is called

[RyanHop3]

When submitting issues, please provide the following information to help maintainers to fix the problem faster:

• Environment: XLPagerTabStrip 7.0, XCode 8.2.1, Swift 3

In the viewDidLoad of the XLPagerTabStrip View Controller I have tried to call self.view.layoutIfNeeded() which is causing the simulator to crash on:

let fromFrame = layoutAttributesForItem(at: IndexPath(item: fromIndex, section: 0))!.frame
within the open func move from the buttonBarView class.

[fdocr]

I had a similar issue using same Xcode & Swift version (XLPagerTabStrip ~> 7.0). The following worked in my case, it might help:

I implemented ButtonBarPagerTabStripViewController without IB, i.e. without setting up an IBOutlet to a view. My crash was caused by the buttonBarView not being retained. Kind of a special implementation (whose isn't?) where I removed the buttonBarView from the ViewController's view and manually added to the navigationBar.

Tried a few different solutions but ended up declaring a dummy variable to force the retain:

...

var buttonBarViewRetainer: UIView?

...


override func viewDidLoad() {
 
     ...

    // This will retain the buttonBarView (declared as weak) to avoid optional unwrapping crash
    buttonBarViewRetainer = buttonBarView
   
    // Custom configuration as used to work before Swift 3.0 migration
    buttonBarView.removeFromSuperview()
     ...

}

[santiagofm]

This issue is addressed in #375 and should be merged into the master branch shortly.

[santiagofm]

Fixed in #380

[Tim77277]

Sorry, I just pulled the latest version and I still ran into the same problem. I went through the #375, #380 but still not be able to solve this issue. Can use some helps here if anyone can give some advise thanks.