我正在尝试创建一个像Facebook菜单幻灯片动画POP框架的动画,或者完全像
InShorts App.
Android Documentation涵盖了这一点.但是在iOS中找不到任何提示.
我试过的是将单元格变换为
- func tableView(tableView: UITableView,willDisplayCell cell: UITableViewCell,forRowAtIndexPath indexPath: NSIndexPath) {
- UIView.animateWithDuration(0.1,animations: { () -> Void in
- cell.transform = CGAffineTransformMakeScale(0.8,0.8)
- })
- }
但是这并不如预期的那样工作.我发现this一个我想要达到的目标.但它在UIView.如果我们在UITableViewCell中动画,我认为最适合我真的很感激有人愿意帮助这个问题. Here是我正在开展的启动项目
解决方法
这个效果可以使用UICollectionView获得.这是UICollectionViewFlowLayout类.
- class UltravisualLayout: UICollectionViewLayout {
- private var contentWidth:CGFloat!
- private var contentHeight:CGFloat!
- private var yOffset:CGFloat = 0
- var maxAlpha:CGFloat = 1
- var minAlpha:CGFloat = 0
- var widthOffset:CGFloat = 35
- var heightOffset:CGFloat = 35
- private var cache = [UICollectionViewLayoutAttributes]()
- private var itemWidth:CGFloat{
- return (collectionView?.bounds.width)!
- }
- private var itemHeight:CGFloat{
- return (collectionView?.bounds.height)!
- }
- private var collectionViewHeight:CGFloat{
- return (collectionView?.bounds.height)!
- }
- private var numberOfItems:Int{
- return (collectionView?.numberOfItemsInSection(0))!
- }
- private var dragOffset:CGFloat{
- return (collectionView?.bounds.height)!
- }
- private var currentItemIndex:Int{
- return max(0,Int(collectionView!.contentOffset.y / collectionViewHeight))
- }
- var nextItemBecomeCurrentPercentage:CGFloat{
- return (collectionView!.contentOffset.y / (collectionViewHeight)) - CGFloat(currentItemIndex)
- }
- override func prepareLayout() {
- cache.removeAll(keepCapacity: false)
- yOffset = 0
- for item in 0 ..< numberOfItems{
- let indexPath = NSIndexPath(forItem: item,inSection: 0)
- let attribute = UICollectionViewLayoutAttributes(forCellWithIndexPath: indexPath)
- attribute.zIndex = -indexPath.row
- if (indexPath.item == currentItemIndex+1) && (indexPath.item < numberOfItems){
- attribute.alpha = minAlpha + max((maxAlpha-minAlpha) * nextItemBecomeCurrentPercentage,0)
- let width = itemWidth - widthOffset + (widthOffset * nextItemBecomeCurrentPercentage)
- let height = itemHeight - heightOffset + (heightOffset * nextItemBecomeCurrentPercentage)
- let deltaWidth = width/itemWidth
- let deltaHeight = height/itemHeight
- attribute.frame = CGRectMake(0,yOffset,itemWidth,itemHeight)
- attribute.transform = CGAffineTransformMakeScale(deltaWidth,deltaHeight)
- attribute.center.y = (collectionView?.center.y)! + (collectionView?.contentOffset.y)!
- attribute.center.x = (collectionView?.center.x)! + (collectionView?.contentOffset.x)!
- yOffset += collectionViewHeight
- }else{
- attribute.frame = CGRectMake(0,itemHeight)
- attribute.center.y = (collectionView?.center.y)! + yOffset
- attribute.center.x = (collectionView?.center.x)!
- yOffset += collectionViewHeight
- }
- cache.append(attribute)
- }
- }
- //Return the size of ContentView
- override func collectionViewContentSize() -> CGSize {
- contentWidth = (collectionView?.bounds.width)!
- contentHeight = CGFloat(numberOfItems) * (collectionView?.bounds.height)!
- return CGSizeMake(contentWidth,contentHeight)
- }
- //Return Attributes whose frame lies in the Visible Rect
- override func layoutAttributesForElementsInRect(rect: CGRect) -> [UICollectionViewLayoutAttributes]? {
- var layoutAttributes = [UICollectionViewLayoutAttributes]()
- for attribute in cache{
- if CGRectIntersectsRect(attribute.frame,rect){
- layoutAttributes.append(attribute)
- }
- }
- return layoutAttributes
- }
- override func shouldInvalidateLayoutForBoundsChange(newBounds: CGRect) -> Bool {
- return true
- }
- override func targetContentOffsetForProposedContentOffset(proposedContentOffset: CGPoint,withScrollingVelocity velocity: CGPoint) -> CGPoint {
- let itemIndex = round(proposedContentOffset.y / (dragOffset))
- let yOffset = itemIndex * (collectionView?.bounds.height)!
- return CGPoint(x: 0,y: yOffset)
- }
- override func layoutAttributesForItemAtIndexPath(indexPath: NSIndexPath) -> UICollectionViewLayoutAttributes? {
- // Logic that calculates the UICollectionViewLayoutAttributes of the item
- // and returns the UICollectionViewLayoutAttributes
- return UICollectionViewLayoutAttributes(forCellWithIndexPath: indexPath)
- }
- }
这是演示项目link …
非常感谢这tutorial.
