ios - 使用 PHImageManager 时，PHAsset 为 UIImage 返回 nil 值

Question

知道为什么在添加 requestImageOption 设置后会为 'thisImage' 返回 nil 吗？如果 options 设置为 nil thisAsset 返回一个值，但它是一个低分辨率图像，绝对不是原始的高分辨率。我正在尝试从 PHAsset (thisAsset) 返回原始图像

    if let thisAsset:PHAsset = info[UIImagePickerController.InfoKey.phAsset] as? PHAsset {
          arrImageIdentifiers.append(thisAsset.localIdentifier)

        let manager = PHImageManager.default()
        let requestImageOption = PHImageRequestOptions()
        requestImageOption.deliveryMode = PHImageRequestOptionsDeliveryMode.highQualityFormat

        manager.requestImage(for: thisAsset, targetSize: PHImageManagerMaximumSize, contentMode: PHImageContentMode.default, options: requestImageOption, resultHandler: {(thisImage, _) in

            Object.tempImage = thisImage

            print("Picture metadata: \(thisAsset)")
            let creationDate = thisAsset.creationDate

            PhotoMeta.createDate = creationDate

            })
            //Get a reference to the camera view controller and call the savePhoto method
            let cameraVC = self.selectedViewController as? CameraViewController

            if let cameraVC = cameraVC {
                cameraVC.savePhoto(image: Object.tempImage!)
            }
    }

Answer 1

将 requestOptions 的 isSynchronus 设置为 true 以解决您的问题:

    let requestImageOption = PHImageRequestOptions()
    requestImageOption.deliveryMode = PHImageRequestOptionsDeliveryMode.highQualityFormat
    requestImageOption.isSynchronous = true

    manager.requestImage(for: thisAsset, targetSize: PHImageManagerMaximumSize, contentMode: PHImageContentMode.default, options: requestImageOption, resultHandler: {(thisImage, _) in

        //....
    }