Get last image from Photos.app?

Question

I have seen other apps do it where you can import the last photo from the Photos app for quick use but as far as I know, I only know how to get A image and not the last (mos

Answer 1

Well, here is a solution of how to load last image from gallery with Swift 3 guys:

func loadLastImageThumb(completion: @escaping (UIImage) -> ()) {
    let imgManager = PHImageManager.default()
    let fetchOptions = PHFetchOptions()
    fetchOptions.fetchLimit = 1
    fetchOptions.sortDescriptors = [NSSortDescriptor(key:"creationDate", ascending: true)]

    let fetchResult = PHAsset.fetchAssets(with: PHAssetMediaType.image, options: fetchOptions)

    if let last = fetchResult.lastObject {
        let scale = UIScreen.main.scale
        let size = CGSize(width: 100 * scale, height: 100 * scale)
        let options = PHImageRequestOptions()


        imgManager.requestImage(for: last, targetSize: size, contentMode: PHImageContentMode.aspectFill, options: options, resultHandler: { (image, _) in
            if let image = image {
                completion(image)
            }
        })
    }

}

If you need more speed, you can also use PHImageRequestOptions and set those:

options.deliveryMode = .fastFormat
options.resizeMode = .fast

And this is the way you get it in your viewController (you should replace GalleryManager.manager with your class):

GalleryManager.manager.loadLastImageThumb { [weak self] (image) in
      DispatchQueue.main.async {
           self?.galleryButton.setImage(image, for: .normal)
      }
}

Answer 2

Great answer from iBrad, worked almost perfectly for me. The exception being that it was returning images at their original orientation (eg. upside down, -90°, etc).

To fix this I simply changed fullResolutionImage to fullScreenImage.

Here:

UIImage *latestPhoto = [UIImage imageWithCGImage:[representation fullScreenImage]];

It now works a treat.

Answer 3

Here is a version in Swift which requests the data and converts it to an UIImage, as the provided version returned an empty UIImage every time

    let fetchOptions = PHFetchOptions()
    fetchOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: true)]

    let fetchResult = PHAsset.fetchAssetsWithMediaType(PHAssetMediaType.Image, options: fetchOptions)

    if let lastAsset: PHAsset = fetchResult.lastObject as? PHAsset {
        let manager = PHImageManager.defaultManager()
        let imageRequestOptions = PHImageRequestOptions()

        manager.requestImageDataForAsset(lastAsset, options: imageRequestOptions) {
            (let imageData: NSData?, let dataUTI: String?,
             let orientation: UIImageOrientation,
             let info: [NSObject : AnyObject]?) -> Void in

             if let imageDataUnwrapped = imageData, lastImageRetrieved = UIImage(data: imageDataUnwrapped) {
                // do stuff with image

             }
        }
    }

Answer 4

Thanks for your answer iBrad Apps.

Just wanted to point out an error prevention for the special case when user has no images on his/her photo roll (strange case I know):

    // Within the group enumeration block, filter to enumerate just photos.
    [group setAssetsFilter:[ALAssetsFilter allPhotos]];

    //Check that the group has more than one picture
    if ([group numberOfAssets] > 0) {
        // Chooses the photo at the last index
        [group enumerateAssetsAtIndexes:[NSIndexSet indexSetWithIndex:([group numberOfAssets] - 1)] options:0 usingBlock:^(ALAsset *alAsset, NSUInteger index, BOOL *innerStop) {

            // The end of the enumeration is signaled by asset == nil.
            if (alAsset) {
                ALAssetRepresentation *representation = [alAsset defaultRepresentation];
                UIImage *latestPhoto = [UIImage imageWithCGImage:[representation fullScreenImage]];

                [self.libraryButton setImage:latestPhoto forState:UIControlStateNormal];
            }
        }];
    }
    else {
      //Handle this special case
    }

Answer 5

I found a typo that I'm embarrassed to admit to me longer than it should have to figure out. Maybe it will save someone else some time.

This line was missing a colon after indexSetWithIndex:

[group enumerateAssetsAtIndexes:[NSIndexSet indexSetWithIndex:[group numberOfAssets] - 1]options:0 usingBlock:^(ALAsset *alAsset, NSUInteger index, BOOL *innerStop) {

Answer 6

Xamarin.iOS version of accepted answer (how to get last image) including all notices from other answers:

  private void ChooseLastTakenPictureImplementation()
    {
        var library = new ALAssetsLibrary();
        // Enumerate just the photos and videos group by using ALAssetsGroupSavedPhotos.
        library.Enumerate(ALAssetsGroupType.SavedPhotos, (ALAssetsGroup assetsGroup, ref bool stop) =>
            {
                if (stop || assetsGroup == null)
                {
                    return;
                }
                //Xamarin does not support ref parameters in nested lamba expressions
                var lambdaStop = false;
                //Check that the group has more than one picture
                if (assetsGroup.Count > 0)
                {
                    // Within the group enumeration block, filter to enumerate just photos.
                    assetsGroup.SetAssetsFilter(ALAssetsFilter.AllPhotos);
                    // Chooses the photo at the last index
                    assetsGroup.Enumerate(NSEnumerationOptions.Reverse, (ALAsset result, int index, ref bool innerStop) =>
                        {
                            // The end of the enumeration is signaled by asset == nil.
                            if (result != null)
                            {
                                var representation = result.DefaultRepresentation;
                                var latestPhoto = new UIImage(representation.GetImage(), representation.Scale, (UIImageOrientation)representation.Orientation);
                                // Stop the enumerations
                                lambdaStop = innerStop = true;
                                // Do something interesting with the AV asset.
                                HandleImageAutoPick(latestPhoto);
                            }
                        });
                    stop = lambdaStop;
                    return;
                }
                else
                {
                    //Handle this special case where user has no pictures
                }
            }, error =>
            {
                // Typically you should handle an error more gracefully than this.
                Debug.WriteLine(error.Description);
            });
    }