diff --git a/Sources/ParallaxPagerView.swift b/Sources/ParallaxPagerView.swift index 32bb939..532f0bf 100644 --- a/Sources/ParallaxPagerView.swift +++ b/Sources/ParallaxPagerView.swift @@ -171,16 +171,21 @@ public final class ParallaxPagerView: UIView { let heightDiff = height - headerHeight headerHeight = height - layoutContentViewControllers() - let heightToBe = headerHeightConstraint?.constant ?? 0 + heightDiff + originalTopInset += heightDiff + let heightToBe = (headerHeightConstraint?.constant ?? 0) + heightDiff + guard let currentDisplayController = currentDisplayController else { return } + let scrollView = scrollViewInViewController(vc: currentDisplayController) ?? internalScrollView + var offset = scrollView.contentOffset + ignoreOffsetChanged = true + updateTopInset(for: scrollView, with: heightDiff) + applyMinimumContentHeight(for: scrollView) if heightToBe > minimumHeaderHeight { headerHeightConstraint?.constant = heightToBe - guard let currentDisplayController = currentDisplayController, - let currentScrollView = scrollViewInViewController(vc: currentDisplayController) - else { return } - let offsetToBe = currentScrollView.contentOffset.y - heightDiff - currentScrollView.setContentOffset(CGPoint(x: internalScrollView.contentOffset.x, y: offsetToBe), animated: animated) + offset.y -= heightDiff } + ignoreOffsetChanged = true + scrollView.contentOffset = offset + ignoreOffsetChanged = false } public func setTabsHeight(_ height: CGFloat, animated: Bool = false) { @@ -191,17 +196,15 @@ public final class ParallaxPagerView: UIView { let diff = height - tabsHeight tabsHeight = height constraint.constant = tabsHeight + originalTopInset += diff guard let vc = currentDisplayController else { return } let scrollView = scrollViewInViewController(vc: vc) ?? internalScrollView - originalTopInset += diff var offset = scrollView.contentOffset - var insets = scrollView.contentInset - insets.top = originalTopInset offset.y -= diff ignoreOffsetChanged = true - scrollView.contentInset = insets + updateTopInset(for: scrollView, with: diff) ignoreOffsetChanged = true scrollView.contentOffset = offset ignoreOffsetChanged = false @@ -229,6 +232,15 @@ public final class ParallaxPagerView: UIView { addSubview(headerView) } + private func updateTopInset(for scrollView: UIScrollView, with delta: CGFloat) { + let offset = scrollView.contentOffset + var insets = scrollView.contentInset + insets.top += delta + scrollView.contentInset = insets + guard scrollView != internalScrollView else { return } + scrollView.contentOffset = offset + } + private func layoutContentViewControllers() { guard let firstVC = viewControllers.first else { return @@ -542,6 +554,10 @@ public final class ParallaxPagerView: UIView { let scrollView = scrollViewInViewController(vc: vc) ?? internalScrollView + let constraintValue = headerHeightConstraint?.constant ?? 0 + let height = max(constraintValue, headerHeight) + originalTopInset = height + tabsHeight + updateTopInset(for: scrollView, with: originalTopInset) updateScrollViewSize(vc: vc, scrollView: scrollView) if hasShownController.contains(vc) == false { @@ -591,24 +607,9 @@ public final class ParallaxPagerView: UIView { internalScrollView.alwaysBounceVertical = false } - let constraintValue = headerHeightConstraint?.constant ?? 0 - let height = max(constraintValue, headerHeight) - originalTopInset = scrollView.contentInset.top + height + tabsHeight if #available(iOS 11.0, *) { scrollView.contentInsetAdjustmentBehavior = .never } - - // fixed bottom tabbar inset - var bottomInset: CGFloat = 0 - if containerViewController.tabBarController?.tabBar.isHidden == false { - bottomInset = containerViewController.tabBarController?.tabBar.bounds.size.height ?? 0 - } - scrollView.contentInset = UIEdgeInsets( - top: originalTopInset, - left: scrollView.contentInset.left, - bottom: bottomInset + scrollView.contentInset.bottom, - right: scrollView.contentInset.right - ) applyMinimumContentHeight(for: scrollView) } @@ -650,10 +651,15 @@ public final class ParallaxPagerView: UIView { UIView.animate(withDuration: duration, animations: { self.internalScrollView.layoutIfNeeded() }) { _ in - self.currentDisplayController?.willMove(toParent: nil) - self.currentDisplayController?.view.removeFromSuperview() - self.currentDisplayController?.removeFromParent() - self.currentDisplayController?.didMove(toParent: nil) + if let currentDisplayed = self.currentDisplayController { + currentDisplayed.willMove(toParent: nil) + currentDisplayed.view.removeFromSuperview() + if let scrollView = self.scrollViewInViewController(vc: currentDisplayed) { + self.updateTopInset(for: scrollView, with: -self.originalTopInset) + } + currentDisplayed.removeFromParent() + currentDisplayed.didMove(toParent: nil) + } self.currentDisplayController = selectedViewController self.pagerDelegate?.didSelectTab(at: index, previouslySelected: previouslySelected)