[Bug Fix] Fix the issue that current item index may be changed after rotation

[flexme]

This fixes the issue https://github.com/nicklockwood/SwipeView/issues/200 .

Basically when the device is rotated, the scroll view's contentSize may be changed since itemSize may be changed (by method updateScrollViewDimensions). However changing contentSize will result in contentOffset being changed by UIKit, then ScrollView.scrollViewDidScroll will be invoked and change the current item index...

This fix ensures that we update the contentOffset based on current item index when contentSize is changed.

[flexme]

BTW, if this is merged, can you release a new version to Cocoapods? Thanks!

[flexme]

Nick, can you merge this? We need it and the updated cocoapods to fix the bug in our app. Thanks!

[flexme]

Hmm, is this project still being maintained?

[AlexAstilean]

For me this fixed the problem when rotating from landscape to portrait while on the last item. But the bug can still be reproduced when rotating from portrait to landscape while on the last item. (Iphone SE,7,7+). It jumps to the second to last item. Any suggestions?

[aravasio]

It hurts to see this amazing library no longer mantained, tbh.

[sQu1rr]

@AlexAstilean this workaround works well for my usecase: http://pastebin.com/tHPaqsaN

[dimovskidamjan]

#208 Fixes this issue with the code that was provided in the pastebin by @sQu1rr .