iOS 14: PHPickerViewController有没有办法同时加载所有资产PHPickerResult

Question

目前，我正在尝试使用PHPickerViewController从照片中同时选择多张图片。所以我想要由用户选择的图像数组，我尝试了太多的方式，但没有运气。这是我的代码，请告诉我有这样做的最佳实践吗？

func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {
        picker.dismiss(animated: true, completion: nil)
        var images: [UIImage?] = []
        var totalConversionsCompleted = 0
        for (index,result) in results.enumerated() {
            result.itemProvider.loadObject(ofClass: UIImage.self, completionHandler: { (object, error) in
                let image = object as? UIImage
                images.append(image)
                totalConversionsCompleted += 1
                if totalConversionsCompleted == index {
                    print("completion happen \(images)")
                }
            })
        }
    }

Answer 1

1-您是否将控制器设置为PHPickerViewController的委派

要做到这一点，您的控制器应该符合PHPickerViewControllerDelegate

class ViewController: UIViewController, PHPickerViewControllerDelegate {

您应该将您的控制器设置为PHPickerViewController的委托

pickerController.delegate = self //if you create PHPickerViewController inside your viewController

然后，您将在此方法上获得结果

func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {

2-如果您不能获得多个选择，您可以更改与PHPickerViewController一起使用的PHPickerConfiguration对象的选择限制

var confing = PHPickerConfiguration(photoLibrary: PHPhotoLibrary.shared())
confing.selectionLimit = 5
let pickerController = PHPickerViewController(configuration: confing)

3-然后您可以处理结果数组中的对象

let identifiers = results.compactMap(\.assetIdentifier)
let fetchResult = PHAsset.fetchAssets(withLocalIdentifiers: identifiers, options: nil)