Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
415 views
in Technique[技术] by (71.8m points)

ios - iPhone - How to create a custom album and give custom names to photos in camera roll programmatically?

I am developing an iPhone photo application, so i need to create a separate album with a name "My Album" in camera roll and i need to save my UIImageView image with custom name for example "My Image.png" inside the newly created directory.

How can i do this?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

Since the AssetsLibrary is deprecated, please use the Photos framework instead (iOS 8 and later).

// Deprecated!
import AssetsLibrary

// Swift 3.0
let assetsLibrary = ALAssetsLibrary()
assetsLibrary.addAssetsGroupAlbum(withName: "NewAlbum", resultBlock: { assetsGroup in
    print(assetsGroup == nil ? "Already created" : "Success")
}, failureBlock: { error in
    print(error)
})

You can use the shared PHPhotoLibrary object to create new photos but you can't give them specific names because you will be working with assets that need to be managed by the Photos.app. Each asset has specific properties. You can fetch objects, request changes, asset/thumbnail loading and caching, etc.

To create a custom album, please use the PHAssetCollectionChangeRequest.creationRequestForAssetCollection(withTitle:).

Brief example:

// Swift 3.0
func createPhotoLibraryAlbum(name: String) {
    var albumPlaceholder: PHObjectPlaceholder?
    PHPhotoLibrary.shared().performChanges({
        // Request creating an album with parameter name
        let createAlbumRequest = PHAssetCollectionChangeRequest.creationRequestForAssetCollection(withTitle: name)
        // Get a placeholder for the new album
        albumPlaceholder = createAlbumRequest.placeholderForCreatedAssetCollection
    }, completionHandler: { success, error in
        if success {
            guard let placeholder = albumPlaceholder else {
                fatalError("Album placeholder is nil")
            }

            let fetchResult = PHAssetCollection.fetchAssetCollections(withLocalIdentifiers: [placeholder.localIdentifier], options: nil)
            guard let album: PHAssetCollection = fetchResult.firstObject else {
                // FetchResult has no PHAssetCollection
                return
            }

            // Saved successfully!
            print(album.assetCollectionType)
        }
        else if let e = error {
            // Save album failed with error
        }
        else {
            // Save album failed with no error
        }
    })
}

Don't forget to import Photos library.

To create a new photo asset on that album, please use the PHAssetChangeRequest.creationRequestForAsset(from:).

// Swift 3.0
func createPhotoOnAlbum(photo: UIImage, album: PHAssetCollection) {
    PHPhotoLibrary.shared().performChanges({
        // Request creating an asset from the image
        let createAssetRequest = PHAssetChangeRequest.creationRequestForAsset(from: photo)
        // Request editing the album
        guard let albumChangeRequest = PHAssetCollectionChangeRequest(for: album) else {
            // Album change request has failed
            return
        }
        // Get a placeholder for the new asset and add it to the album editing request
        guard let photoPlaceholder = createAssetRequest.placeholderForCreatedAsset else {
            // Photo Placeholder is nil
            return
        }
        albumChangeRequest.addAssets([photoPlaceholder] as NSArray)
    }, completionHandler: { success, error in
        if success {
            // Saved successfully!
        }
        else if let e = error {
            // Save photo failed with error
        }
        else {
            // Save photo failed with no error
        }
    })
}

UPDATE:

We need to request access to be able to use the Photos library:

PHPhotoLibrary.requestAuthorization { status in
     switch status {
     ...
}

As of iOS 10 and above we also need to add entry for access in the target .plist file for "Privacy - Photo Library Usage Description":

<key>NSPhotoLibraryUsageDescription</key>
<string>Access to photos is needed to provide app features</string>

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...