Saving Image found in UIImagePicker to Upload to Database - ios

Question

I have successfully implemented an Image Picker in my app - it pulls pictures from the library and you can select specific images.
Now after the user selects the image, I want to store the image to a variable somehow in my code so that I can upload the image to a database.
Here's what I currently have in my code:
public class PhotoPickerService : IPhotoPickerService
{
TaskCompletionSource<Stream> taskCompletionSource;
UIImagePickerController imagePicker;
public Task<Stream> GetImageStreamAsync()
{
//Create and define UIImagePickerController
imagePicker = new UIImagePickerController
{
SourceType = UIImagePickerControllerSourceType.PhotoLibrary,
MediaTypes = UIImagePickerController.AvailableMediaTypes(UIImagePickerControllerSourceType.PhotoLibrary)
};
//Set Event Handlers
imagePicker.FinishedPickingMedia += OnImagePickerFinishedPickingMedia;
imagePicker.Canceled += OnImagePickerCancelled;
//Present UIImagePickerController
UIWindow window = UIApplication.SharedApplication.KeyWindow;
var viewController = window.RootViewController;
viewController.PresentViewController(imagePicker, true, null);
//Return Task Object
taskCompletionSource = new TaskCompletionSource<Stream>();
return taskCompletionSource.Task;
}
void OnImagePickerFinishedPickingMedia(object sender, UIImagePickerMediaPickedEventArgs args)
{
//assigns var image to the edited image if there is one, otherwise it'll assign it to the original image
UIImage image = args.EditedImage ?? args.OriginalImage;
if (image != null)
{
//Convert UIImage to .NET stream object
NSData data;
if(args.ReferenceUrl.PathExtension.Equals("PNG") || args.ReferenceUrl.PathExtension.Equals("png"))
{
data = image.AsPNG();
//Console.WriteLine(data);
}
else
{
data = image.AsJPEG(1);
Console.WriteLine(data);
}
Stream stream = data.AsStream();
UnregisterEventHandlers();
taskCompletionSource.SetResult(stream);
}
else
{
UnregisterEventHandlers();
taskCompletionSource.SetResult(null);
}
imagePicker.DismissModalViewController(true);
}
void OnImagePickerCancelled(object sender, EventArgs args)
{
UnregisterEventHandlers();
taskCompletionSource.SetResult(null);
imagePicker.DismissModalViewController(true);
}
void UnregisterEventHandlers()
{
imagePicker.FinishedPickingMedia -= OnImagePickerFinishedPickingMedia;
imagePicker.Canceled -= OnImagePickerCancelled;
}
Here is what I'm wondering: I need to upload this image to a database with the datatype varbinary. The image currently has the datatype NSData which as I've researched is used to store items such as pictures with raw binary data. Am I storing this correctly as of right now to upload to a database? Do I need to do some sort of conversion?

Answer 1

You should implement UIImagePickerControllerDelegate to your ViewController
import UIKit
import AVFoundation
import MobileCoreServices
class ViewController: UIViewController {
var choosenImageData: Data?
fileprivate lazy var imagePicker: UIImagePickerController = {
let imagePicker = UIImagePickerController()
imagePicker.delegate = self
imagePicker.mediaTypes = [(kUTTypeImage as String)]
imagePicker.allowsEditing = false
return imagePicker
}()
#IBAction func cameraButtonPressed(_ sender: Any) {
self.imagePicker.sourceType = .camera // .photoLibrary
self.present(self.imagePicker, animated: true, completion: nil)
}
}
extension ViewController: UIImagePickerControllerDelegate {
func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey: Any]) {
if let image = info[UIImagePickerController.InfoKey.originalImage] as? UIImage {
self.choosenImageData = image.jpeg(.lowest)
}
}
}
Use this extension to convert UIImage to Data
import Foundation
// MARK: - Compress UIImage Quality
extension UIImage {
enum JPEGQuality: CGFloat {
case lowest = 0
case low = 0.25
case medium = 0.5
case high = 0.75
case highest = 1
}
/// Returns the data for the specified image in JPEG format.
/// If the image object’s underlying image data has been purged, calling this function forces that data to be reloaded into memory.
/// - returns: A data object containing the JPEG data, or nil if there was a problem generating the data. This function may return nil if the image has no data or if the underlying CGImageRef contains data in an unsupported bitmap format.
func jpeg(_ quality: JPEGQuality) -> Data? {
return self.jpegData(compressionQuality: quality.rawValue)
}
}
After you have successfully retrieved selected image data, you can perform your tasks to save/upload to your online or local DB.

Answer 2

This answer is an alternative that you might consider instead of using UIImagePicker
Here this function will allow you to get the photos on the library on the phone, so you can use the result of this function which will be an away of [UIImage] and store it on a variable I understand you need to do. but to actually check what image what the user to upload you will need to build a CollectionView for example and give the user the option to select the photos to upload, will the user selecting the photos from the collection view you can save the index that you can use to define which pictures to upload.
Note: you can specify the request option: (the delivery mode defines the quality of the image you can use fastFormat , opportunistic or highQualityFormat)
requestOptions.isSynchronous = true
requestOptions.deliveryMode = .opportunistic
This is the function just a copy past on your project will do the trick
private func getPhotos() -> [UIImage]? {
// Image Array declaration
var imageArray = [UIImage]()
// Image manager and specify the request option
let imageManager = PHImageManager.default()
let requestOptions = PHImageRequestOptions()
requestOptions.isSynchronous = true
requestOptions.deliveryMode = .opportunistic
// Sorted by creation date
let fetchOptions = PHFetchOptions()
fetchOptions.sortDescriptors = [NSSortDescriptor(key: "creationDate", ascending: false)]
// Perform the fetch and appand to Image array
if let fetchResult: PHFetchResult = PHAsset.fetchAssets(with: .image, options: fetchOptions) {
if fetchResult.count > 0 {
for i in 0..<fetchResult.count {
imageManager.requestImage(for: fetchResult.object(at: i), targetSize: CGSize(width: 280, height: 280), contentMode: .aspectFill, options: requestOptions) { image, error in
imageArray.append(image!)
}
}
return imageArray
} else {
print("You dont have any photos!")
}
}
return nil
}