107 lines
3.8 KiB
Swift
107 lines
3.8 KiB
Swift
import SwiftUI
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struct AsyncImageView: View {
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let url: String
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let nums: [Int]
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let index: Int
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@State private var image: UIImage?
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@State private var isLoading = false
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@State private var error: Error?
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// 静态属性，用于维护当前加载的索引范围
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private static var currentlyLoadingIndices: Set<Int> = []
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private static let maxConcurrentLoads = 4
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var body: some View {
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Group {
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if let image = image {
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Image(uiImage: image)
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.resizable()
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.aspectRatio(contentMode: .fit)
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} else if isLoading {
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ProgressView()
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} else if error != nil {
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VStack {
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Image(systemName: "exclamationmark.triangle")
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.foregroundColor(.red)
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Text(error?.localizedDescription ?? "未知错误")
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.font(.caption)
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}
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} else {
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Color.gray.opacity(0.3)
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}
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}
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.onAppear {
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loadImage()
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}
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}
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private func loadImage() {
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// 如果已经在加载中，或者超出最大加载限制，直接返回
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guard !Self.currentlyLoadingIndices.contains(index),
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Self.currentlyLoadingIndices.count < Self.maxConcurrentLoads else {
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return
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}
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// 添加当前索引到加载集合
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Self.currentlyLoadingIndices.insert(index)
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isLoading = true
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error = nil
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// 确保 nums 和 index 对齐，避免越界
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guard let decodeNum = nums[safe: index] else {
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print("错误：nums 中未找到索引 \(index) 对应的值，可能 API 数据不一致")
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Self.currentlyLoadingIndices.remove(index)
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return
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}
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print("调试信息：图片 URL: \(url), 解密参数 num: \(decodeNum), 索引: \(index)")
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guard let imageUrl = URL(string: url) else {
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self.error = NSError(domain: "无效的URL", code: 1, userInfo: nil)
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isLoading = false
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Self.currentlyLoadingIndices.remove(index)
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return
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}
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// 加载图片数据
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URLSession.shared.dataTask(with: imageUrl) { data, response, error in
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DispatchQueue.main.async {
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// 移除当前索引
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Self.currentlyLoadingIndices.remove(index)
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self.isLoading = false
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if let error = error {
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self.error = error
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print("图片加载失败，错误: \(error.localizedDescription)")
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return
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}
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guard let httpResponse = response as? HTTPURLResponse,
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(200...299).contains(httpResponse.statusCode),
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let data = data, !data.isEmpty else {
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self.error = NSError(domain: "无效响应", code: 2, userInfo: nil)
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print("图片加载失败，无效响应或数据为空")
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return
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}
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if let loadedImage = UIImage(data: data) {
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print("图片加载成功，开始解密...")
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let decodedImage = loadedImage.decodeImage(num: decodeNum)
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self.image = decodedImage
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print("解密完成，图片已更新")
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} else {
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self.error = NSError(domain: "图片数据解码失败", code: 4, userInfo: nil)
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print("图片数据解码失败")
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}
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}
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}.resume()
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}
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}
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extension Array {
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subscript(safe index: Int) -> Element? {
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return indices.contains(index) ? self[index] : nil
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}
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}
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