如何从自定义相册中获取所有图像？
var fetchOptions = PHFetchOptions()
fetchOptions.sortDescriptors = [NSSortDescriptor(key:"creationDate", ascending: false)]
fetchOptions.predicate = NSPredicate(format: "mediaType = %d", PHAssetMediaType.Image.rawValue)
let allImages:PHFetchResult = PHAsset.fetchKeyAssetsInAssetCollection(albumList[index].collection, options: fetchOptions)
这个代码块只取一些。谢谢。
- > albumList[index].collection的类型是PHAssetCollection
对于Swift 4
使用这个答案https://stackoverflow.com/a/28904792/4795651为自己编辑了一点。
import Photos
func fetchCustomAlbumPhotos()
{
let albumName = "Album Name Here"
var assetCollection = PHAssetCollection()
var albumFound = Bool()
var photoAssets = PHFetchResult<AnyObject>()
let fetchOptions = PHFetchOptions()
fetchOptions.predicate = NSPredicate(format: "title = %@", albumName)
let collection:PHFetchResult = PHAssetCollection.fetchAssetCollections(with: .album, subtype: .any, options: fetchOptions)
if let firstObject = collection.firstObject{
//found the album
assetCollection = firstObject
albumFound = true
}
else { albumFound = false }
_ = collection.count
photoAssets = PHAsset.fetchAssets(in: assetCollection, options: nil) as! PHFetchResult<AnyObject>
let imageManager = PHCachingImageManager()
photoAssets.enumerateObjects{(object: AnyObject!,
count: Int,
stop: UnsafeMutablePointer<ObjCBool>) in
if object is PHAsset{
let asset = object as! PHAsset
print("Inside If object is PHAsset, This is number 1")
let imageSize = CGSize(width: asset.pixelWidth,
height: asset.pixelHeight)
/* For faster performance, and maybe degraded image */
let options = PHImageRequestOptions()
options.deliveryMode = .fastFormat
options.isSynchronous = true
imageManager.requestImage(for: asset,
targetSize: imageSize,
contentMode: .aspectFill,
options: options,
resultHandler: {
(image, info) -> Void in
self.photo = image!
/* The image is now available to us */
self.addImgToArray(uploadImage: self.photo!)
print("enum for image, This is number 2")
})
}
}
}
func addImgToArray(uploadImage:UIImage)
{
self.images.append(uploadImage)
}
对于Swift 2.1
import Photos
func FetchCustomAlbumPhotos()
{
var albumName = "SwiftAlbum"
var assetCollection = PHAssetCollection()
var albumFound = Bool()
var photoAssets = PHFetchResult()
let fetchOptions = PHFetchOptions()
fetchOptions.predicate = NSPredicate(format: "title = %@", albumName)
let collection:PHFetchResult = PHAssetCollection.fetchAssetCollectionsWithType(.Album, subtype: .Any, options: fetchOptions)
if let first_Obj:AnyObject = collection.firstObject{
//found the album
assetCollection = collection.firstObject as! PHAssetCollection
albumFound = true
}
else { albumFound = false }
var i = collection.count
photoAssets = PHAsset.fetchAssetsInAssetCollection(assetCollection, options: nil)
let imageManager = PHCachingImageManager()
// let imageManager = PHImageManager.defaultManager()
photoAssets.enumerateObjectsUsingBlock{(object: AnyObject!,
count: Int,
stop: UnsafeMutablePointer<ObjCBool>) in
if object is PHAsset{
let asset = object as! PHAsset
print("Inside If object is PHAsset, This is number 1")
let imageSize = CGSize(width: asset.pixelWidth,
height: asset.pixelHeight)
/* For faster performance, and maybe degraded image */
let options = PHImageRequestOptions()
options.deliveryMode = .FastFormat
options.synchronous = true
imageManager.requestImageForAsset(asset,
targetSize: imageSize,
contentMode: .AspectFill,
options: options,
resultHandler: {
(image, info) -> Void in
self.photo = image!
/* The image is now available to us */
self.addImgToArray(self.photo)
print("enum for image, This is number 2")
})
}
}
}
func addImgToArray(uploadImage:UIImage)
{
self.images.append(uploadImage)
}
这是一张自定义相册，所以您要做的就是将它添加到中间的代码中：
import Photos
class CustomPhotoAlbum {
static let albumName = "Album"
static let sharedInstance = CustomPhotoAlbum()
var assetCollection: PHAssetCollection!
init() {
func fetchAssetCollectionForAlbum() -> PHAssetCollection! {
let fetchOptions = PHFetchOptions()
fetchOptions.predicate = NSPredicate(format: "title = %@", CustomPhotoAlbum.albumName)
let collection = PHAssetCollection.fetchAssetCollections(with: .album, subtype: .any, options: fetchOptions)
if let firstObject: AnyObject = collection.firstObject {
return collection.firstObject as? PHAssetCollection
}
return nil
}
if let assetCollection = fetchAssetCollectionForAlbum() {
self.assetCollection = assetCollection
return
}
PHPhotoLibrary.shared().performChanges({
PHAssetCollectionChangeRequest.creationRequestForAssetCollection(withTitle: CustomPhotoAlbum.albumName)
}) { success, _ in
if success {
self.assetCollection = fetchAssetCollectionForAlbum()
}
}
}
func saveImage(image: UIImage) {
if assetCollection == nil {
return // If there was an error upstream, skip the save.
}
PHPhotoLibrary.shared().performChanges({
let assetChangeRequest = PHAssetChangeRequest.creationRequestForAsset(from: image)
let assetPlaceholder = assetChangeRequest.placeholderForCreatedAsset
let albumChangeRequest = PHAssetCollectionChangeRequest(for: self.assetCollection)
albumChangeRequest?.addAssets([assetPlaceholder] as NSFastEnumeration)
}, completionHandler: nil)
}
}
然后，要获取相册中的所有图片，请使用以下代码：
func getAlbum(title: String, completionHandler: @escaping (PHAssetCollection?) -> ()) {
DispatchQueue.global(qos: .background).async { [weak self] in
let fetchOptions = PHFetchOptions()
fetchOptions.predicate = NSPredicate(format: "title = %@", title)
let collections = PHAssetCollection.fetchAssetCollections(with: .album, subtype: .any, options: fetchOptions)
if let album = collections.firstObject {
completionHandler(album)
} else {
self?.createAlbum(withTitle: title, completionHandler: { (album) in
completionHandler(album)
})
}
}
}
要调用此函数，请使用以下示例：
getAlbum(title: "Album") { [weak self] assetCollection in
guard let this = self else { return }
guard assetCollection != nil else { return }
print(assetCollection!)
}
如果要创建自定义相册，请使用此功能：
func createAlbum(withTitle title: String, completionHandler: @escaping (PHAssetCollection?) -> ()) {
DispatchQueue.global(qos: .background).async {
var placeholder: PHObjectPlaceholder?
PHPhotoLibrary.shared().performChanges({
let createAlbumRequest = PHAssetCollectionChangeRequest.creationRequestForAssetCollection(withTitle: title)
placeholder = createAlbumRequest.placeholderForCreatedAssetCollection
}, completionHandler: { (created, error) in
var album: PHAssetCollection?
if created {
let collectionFetchResult = placeholder.map { PHAssetCollection.fetchAssetCollections(withLocalIdentifiers: [$0.localIdentifier], options: nil) }
album = collectionFetchResult?.firstObject
}
completionHandler(album)
})
}
}
如果未创建相册，则将在getAlbum中调用此函数。
SWIFT 4
func FetchCustomAlbumPhotos()
{
let albumName = "AlbumName"
var assetCollection = PHAssetCollection()
var albumFound = Bool()
var photoAssets = PHFetchResult<AnyObject>()
let fetchOptions = PHFetchOptions()
fetchOptions.predicate = NSPredicate(format: "title = %@", albumName)
let collection:PHFetchResult = PHAssetCollection.fetchAssetCollections(with: .album, subtype: .any, options: fetchOptions)
if let _:AnyObject = collection.firstObject{
//found the album
assetCollection = collection.firstObject!
albumFound = true
}
else { albumFound = false }
_ = collection.count
photoAssets = PHAsset.fetchAssets(in: assetCollection, options: nil) as! PHFetchResult<AnyObject>
let imageManager = PHCachingImageManager()
// let imageManager = PHImageManager.defaultManager()
photoAssets.enumerateObjects{(object: AnyObject!,
count: Int,
stop: UnsafeMutablePointer<ObjCBool>) in
if object is PHAsset{
let asset = object as! PHAsset
print("Inside If object is PHAsset, This is number 1")
let imageSize = CGSize(width: asset.pixelWidth,
height: asset.pixelHeight)
/* For faster performance, and maybe degraded image */
let options = PHImageRequestOptions()
options.deliveryMode = .fastFormat
options.isSynchronous = true
imageManager.requestImage(for: asset,
targetSize: imageSize,
contentMode: .aspectFit ,
options: options,
resultHandler: {
(image, info) -> Void in
print("Image \(String(describing: image))")
//self.photo = image!
/* The image is now available to us */
//self.addImgToArray(self.photo)
print("enum for image, This is number 2")
})
}
}
}