Flutter在M1 Mac搭配iPhone真机用image_picker遇Firebase Storage错误求助

问题描述 #

我是Flutter新手，使用image_picker包从iOS相册选择图片时返回值为null，同时出现以下错误：

[VERBOSE-2:dart_vm_initializer.cc(41)] Unhandled Exception: [firebase_storage/object-not-found] No object exists at the desired reference

查阅包文档得知模拟器存在已知问题，改用iPhone 14 Pro Max真机测试后仅成功过一次，恳请帮忙排查问题，如需更多信息请告知！

相关代码 #

String? photoUrl = " ";
File? image;

Future pickImage() async {
    try {
      final image = await ImagePicker()
          .pickImage(source: ImageSource.gallery, requestFullMetadata: false);
      if (image == null) return;

      Reference ref = FirebaseStorage.instance.ref().child("profilepic.jpg");
      await ref.putFile(File(image.path));
      await ref.getDownloadURL().then((value) {print(value); setState(() {
        photoUrl = value;
      });});
    } on PlatformException catch (e) {
      debugPrint('Failed to pick image: $e');
    }
  }

profilePic() {
    final Size size = MediaQuery.of(context).size;
    return SizedBox(
      height: size.height * 0.185,
      width: double.infinity,
      child: Column(children: [
        const Spacer(),
        photoUrl != null
            ?
            GestureDetector(
                onTap: () {
                  pickImage();
                },
                child: Container(
                  height: 120,
                  width: 160,
                  decoration: const BoxDecoration(
                    color: Colors.blue,
                    borderRadius: BorderRadius.all(
                      Radius.circular(20),
                    ),
                  ),
                  child: const Icon(
                    Icons.person,
                    size: 50,
                    color: Colors.white,
                  ),
                ),
              ):Image.network(photoUrl!),
      ],
      ),
    );
  }

flutter doctor信息 #

[✓] Flutter (Channel stable, 3.7.0, on macOS 12.6.1 21G217 darwin-arm64, locale en-US)
• Flutter version 3.7.0 on channel stable at /Users/myronsp/Developer/flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision b06b8b2710 (9 days ago), 2023-01-23 16:55:55 -0800
• Engine revision b24591ed32
• Dart version 2.19.0
• DevTools version 2.20.1

[✓] Android toolchain - develop for Android devices (Android SDK version 33.0.0)
• Android SDK at /Users/myronsp/Library/Android/sdk
• Platform android-33, build-tools 33.0.0
• ANDROID_HOME = /Users/myronsp/Library/Android/sdk
• Java binary at: /Applications/Android Studio.app/Contents/jre/Contents/Home/bin/java
• Java version OpenJDK Runtime Environment (build 11.0.15+0-b2043.56-8887301)
• All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 14.2)
• Xcode at /Applications/Xcode.app/Contents/Developer
• Build 14C18
• CocoaPods version 1.11.3

[✓] Chrome - develop for the web
• Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2022.1)
• Android Studio at /Applications/Android Studio.app/Contents
• Flutter plugin can be installed from:
🔨 https://plugins.jetbrains.com/plugin/9212-flutter
• Dart plugin can be installed from:
🔨 https://plugins.jetbrains.com/plugin/6351-dart
• Java version OpenJDK Runtime Environment (build 11.0.15+0-b2043.56-8887301)

[✓] Connected device (5 available)
• sdk gphone64 arm64 (mobile) • emulator-5554                        • android-arm64  • Android 13 (API 33) (emulator)
• Myron’s iPhone (mobile)     • 00008120-00016D500A80C01E            • ios            • iOS 16.0.2 20A380
• iPhone 14 Pro Max (mobile)  • B8ACBFEA-35E5-4D2C-810C-46100D17EE63 • ios            • com.apple.CoreSimulator.SimRuntime.iOS-16-2 (simulator)
• macOS (desktop)             • macos                                • darwin-arm64   • macOS 12.6.1 21G217 darwin-arm64
• Chrome (web)                • chrome                               • web-javascript • Google Chrome 109.0.5414.119

排查建议 #

1. 修复image_picker返回null问题 #

• 配置iOS相册权限：在Info.plist中添加以下键值对，确保权限描述清晰：

  <key>NSPhotoLibraryUsageDescription</key>
  <string>需要访问相册以选择头像</string>
  <key>NSPhotoLibraryAddUsageDescription</key>
  <string>需要访问相册以保存图片</string>
  

• 检查真机权限：进入iPhone「设置」→你的应用名称→「照片」，确认权限设置为「允许访问所有照片」
• 升级image_picker包：执行flutter pub upgrade image_picker，使用最新稳定版适配iOS 16+系统

2. 解决Firebase Storage异常 #

• 使用唯一文件名：每次上传用不同文件名避免覆盖，同时防止上传失败后引用不存在，修改存储引用代码：

  Reference ref = FirebaseStorage.instance.ref().child("profile_${DateTime.now().millisecondsSinceEpoch}.jpg");
  

• 捕获Firebase异常：补充异常捕获逻辑，打印详细错误信息：

  } on FirebaseException catch (e) {
    debugPrint('Firebase Storage error: $e');
  }
  

• 检查存储规则：确保Firebase控制台的存储规则允许读写（测试阶段可临时开放，上线后需修改为安全规则）：

  rules_version = '2';
  service firebase.storage {
    match /b/{bucket}/o {
      match /{allPaths=**} {
        allow read, write: if request.auth != null;
      }
    }
  }
  

3. 修复UI逻辑错误 #

• 修正初始值和显示逻辑：photoUrl初始值设为null，并反转显示判断逻辑，修改后代码片段：

  String? photoUrl = null;
  
  // ...
  
  photoUrl == null
      ? GestureDetector(/* 选择图片按钮 */)
      : Image.network(photoUrl!),
  

内容的提问来源于stack exchange，提问作者MSP