如何显示库中的实时照片视频并在iOS Swift的收藏夹视图中显示？

Question

For Displaying the Live-Photos:

func fetchLivePhotos() {

    let options = PHFetchOptions()

    options.sortDescriptors = [ NSSortDescriptor(key: "creationDate", ascending: false) ]

    options.predicate = NSPredicate(format: "(mediaSubtype & %d) != 0",PHAssetMediaSubtype.photoLive.rawValue)

    DispatchQueue.global(qos: DispatchQoS.QoSClass.default).async {
        self.livePhotoAssets = PHAsset.fetchAssets(with: options)

        DispatchQueue.main.async {
            self.collectionView?.reloadData()
        }
    }
}

And For Displaying in Grid Code is below:

 func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "MediaCell", for: indexPath) as! MediaCell

        if let asset = livePhotoAssets?[indexPath.row]{
            let options = PHImageRequestOptions()
            options.isNetworkAccessAllowed = true

            let targetSize = CGSize(width: 200, height: 200)
            PHImageManager.default().requestImage(for: asset, targetSize: targetSize, contentMode: .aspectFill, options: options, resultHandler: { (image: UIImage?, info: [AnyHashable : Any]?) in
                cell.backgroundImageView.image = image
            })
        }

        cell.selectedImage.isHidden = true
        return cell
    }

And For Fetching Video, I am using this predicate:

  option.predicate = NSPredicate(format: "mediaType == %i",PHAssetMediaType.video.rawValue)

But in Collectionview both are not display.

Answer 1

try to override the method from UICollectionViewDataSource protocol:

public func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    if let count = livePhotoAssets?.count {
        return count
    }
    return 0
}

also:

don't forget to set the ViewController as table view datasource. don't forget to attach collectionView property in storyboard, if you are create it from storyboard.

i have build it and works perfectly.