ios - UICollectionView 水平滚动照片库与 swift

Question

我正在尝试使用 UICollectionView 和 Swift 制作照片库。我想全屏显示照片并向右滑动以获取下一张图片。我有一个肖像框的工作代码，但是一旦我转到风景，我的单元格似乎没有重新调整到正确的位置和大小。

意味着它保持与纵向屏幕相同的宽度、高度、x position和y position每时每刻。我在纵向和横向框架上也遇到此错误:

->未定义 UICollectionViewFlowLayout 的行为，因为:

->项目高度必须小于 UICollectionView 的高度减去部分插入的顶部和底部值。

我在网上寻找答案并尝试了所有可能的解决方案，但它似乎对我不起作用。让我知道是否有人可以帮助解决这个问题。非常感谢。

这是我的代码:

import UIKit

class ImageDetailViewController: UIViewController, UICollectionViewDelegate, UICollectionViewDataSource, UICollectionViewDelegateFlowLayout,UINavigationControllerDelegate {


@IBOutlet weak var imgDetailCollectionView: UICollectionView!

var index: Int!
var imageItems: Array<Items> = []
var currentIndex: CGFloat!
var size = UIScreen.mainScreen().bounds.size
init(index: Int , imageItems: Array<Items>) {
    self.index = index
    self.imageItems = imageItems
    super.init(nibName: "ImageDetailViewController", bundle: NSBundle.mainBundle())
}

required init(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}

override func viewDidLoad() {
    super.viewDidLoad()


    imgDetailCollectionView.registerNib(UINib(nibName: "ImageDetailCollectionViewCell", bundle: nil), forCellWithReuseIdentifier: "ImageDetailCollectionViewCell")
    //self.automaticallyAdjustsScrollViewInsets = false
    imgDetailCollectionView.setZoomScale(0.5, animated: true)

}




override func viewDidLayoutSubviews() {
    imgDetailCollectionView.scrollRectToVisible(CGRectMake(320 * CGFloat(index), 0, 320 , 240), animated: false)
}



override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int{

    return self.imageItems.count
}


func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell{






    var cell = imgDetailCollectionView.dequeueReusableCellWithReuseIdentifier("ImageDetailCollectionViewCell", forIndexPath: indexPath) as ImageDetailCollectionViewCell

    cell.setup(imageItems[indexPath.row].url!)

    if(UIDeviceOrientationIsPortrait(UIDevice.currentDevice().orientation)){


        self.imgDetailCollectionView.collectionViewLayout.invalidateLayout()

        var frame = cell.frame
        frame.size = CGSizeMake(size.width, size.height)
        cell.frame = frame

    }else{
        self.imgDetailCollectionView.collectionViewLayout.invalidateLayout()

        var frame = cell.frame
        frame.size = CGSizeMake(size.height, size.width)
        cell.frame = frame
    }

    return cell

}


func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {

    var size = UIScreen.mainScreen().bounds.size

    if(UIDeviceOrientationIsPortrait(UIDevice.currentDevice().orientation)){


        return CGSizeMake(size.width, size.height)


    }else{

        return CGSizeMake(size.height, size.width)
    }



}

func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumLineSpacingForSectionAtIndex section: Int) -> CGFloat {
    return 0
}

func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, minimumInteritemSpacingForSectionAtIndex section: Int) -> CGFloat {
    return 0
}


override func willRotateToInterfaceOrientation(toInterfaceOrientation: UIInterfaceOrientation, duration: NSTimeInterval) {
    self.imgDetailCollectionView.collectionViewLayout.invalidateLayout()

    var currentOffset = self.imgDetailCollectionView.contentOffset
    self.currentIndex = currentOffset.x / imgDetailCollectionView.frame.size.width

}


override func didRotateFromInterfaceOrientation(fromInterfaceOrientation: UIInterfaceOrientation) {

    var currentSize = imgDetailCollectionView.bounds.size
    var offset = self.currentIndex * currentSize.width
    imgDetailCollectionView.setContentOffset(CGPointMake(offset, 0), animated: false)

    imgDetailCollectionView.reloadData()
}

override func willAnimateRotationToInterfaceOrientation(toInterfaceOrientation: UIInterfaceOrientation, duration: NSTimeInterval) {

    self.imgDetailCollectionView.collectionViewLayout.invalidateLayout()
}
}

Answer 1

您的问题是您正在检查方向并在横向模式下使用高度作为宽度。这是不正确的。当设备旋转时，width 属性将返回设备纵向时的实际高度。

func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
    var cell = imgDetailCollectionView.dequeueReusableCellWithReuseIdentifier("ImageDetailCollectionViewCell", forIndexPath: indexPath) as ImageDetailCollectionViewCell
    cell.setup(imageItems[indexPath.row].url!)
    cell.frame.size = view.frame.size
    return cell
}
func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {
    return CGSizeMake(view.frame.width, view.frame.height)
}

另外注意，苹果建议您使用 viewWillTransitionToSize(size: CGSize, withTransitionCoordinator coordinator: UIViewControllerTransitionCoordinator) 方法，因为这是较新的 API。此外，在 iOS9 中，如果您改用此方法，您将通过使用此方法启用多任务处理功能。