PHImageManager 获取请求需要很长时间才能响应

Question

当我调用此函数从照片中获取最后一张图像时，UI 被阻塞了大约 4 秒。有什么想法吗？

这是我的代码


import SwiftUI
import Photos

class GalleryManager: NSObject {}

extension GalleryManager {
    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 size = CGSize(width: 100, height: 100)
            let options = PHImageRequestOptions()
            options.resizeMode = .fast
            options.deliveryMode = .fastFormat
            options.isSynchronous = true
            
            imgManager.requestImage(for: last, targetSize: size, contentMode: PHImageContentMode.aspectFill, options: options, resultHandler: { (image, _) in
                if let image = image {
                    completion(image)
                }
            })
        }
    }
}

Answer 1

你的所作所为是错误和违法的。当您的代码在主线程上运行时，您说的是 options.isSynchronous = true 。只需删除该行并在图像到达时对其进行处理（可能多次）。

PHImageManager 获取请求需要很长时间才能响应

PHImageManager fetch request take long time to response

swift

phimagemanager