Merge branch 'grant.zhou/github_multisections' into 'master'

ignore bounds change when setCurrentPage

See merge request grant/CollectionViewPagingLayout!3

Author: grant

Lib/CollectionViewPagingLayout.swift

@@ -65,9 +65,10 @@ public class CollectionViewPagingLayout: UICollectionViewLayout {
 
 
     // MARK: UICollectionViewLayout
+    var ignoreBoundsChange : Bool = false
 
     override public func shouldInvalidateLayout(forBoundsChange newBounds: CGRect) -> Bool {
-        true
+        !ignoreBoundsChange
     }
 
     override public func layoutAttributesForElements(in rect: CGRect) -> [UICollectionViewLayoutAttributes]? {
@@ -174,7 +175,9 @@ public class CollectionViewPagingLayout: UICollectionViewLayout {
         offset = max(0, offset)
         offset = min(offset, maxPossibleOffset)
         let contentOffset: CGPoint = scrollDirection == .horizontal ? CGPoint(x: offset, y: 0) : CGPoint(x: 0, y: offset)
+        ignoreBoundsChange = true
         collectionView?.setContentOffset(contentOffset, animated: animated)
+        ignoreBoundsChange = false
         updateCurrentPageIfNeeded(basedOn: contentOffset)
     }
 }