I'm building Gallery app like a iOS standard Photos App. (Swift 4.1)
I want to fetch the thumbnails, titles, and total number of images that I can see when I launch the standard photo app.
The Photos framework seems more complex than I thought.
It is not easy to find a way to explain why, and what procedures should be approached.
Can you tell me about this?
The minimum number of steps to achieve what you are asking is:
// import the framework
import Photos
// get the albums list
let albumList = PHAssetCollection.fetchAssetCollections(with: .album, subtype: .albumRegular, options: nil)
// you can access the number of albums with
albumList.count
// individual objects with
let album = albumList.object(at: 0)
// eg. get the name of the album
album.localizedTitle
// get the assets in a collection
func getAssets(fromCollection collection: PHAssetCollection) -> PHFetchResult<PHAsset> {
let photosOptions = PHFetchOptions()
photosOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: true)]
photosOptions.predicate = NSPredicate(format: "mediaType == %d", PHAssetMediaType.image.rawValue)
return PHAsset.fetchAssets(in: collection, options: photosOptions)
}
// eg.
albumList.enumerateObjects { (coll, _, _) in
let result = self.getAssets(fromCollection: coll)
print("\(coll.localizedTitle): \(result.count)")
}
// Now you can:
// access the count of assets in the PHFetchResult
result.count
// get an asset (eg. in a UITableView)
let asset = result.object(at: indexPath.row)
// get the "real" image
PHCachingImageManager.default().requestImage(for: asset, targetSize: CGSize(width: 200, height: 200), contentMode: .aspectFill, options: nil) { (image, _) in
// do something with the image
}
I also suggest to take a look at the Apple sample code for the Photos framework, is not hard to follow, together with the Photos framework documentation.