MAUI Android端调用SecureStorage.SetAsync抛出FileNotFoundException问题

问题场景 #

调用自定义的SetAsync方法时抛出FileNotFoundException，查阅官方文档仅要求清单文件添加两项配置，但问题仍未解决。

代码实现 #

public async Task SetAsync(string key, string value)
{
  await SecureStorage.SetAsync(key, value);
}

AndroidManifest.xml 配置 #

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android">
    <uses-sdk android:minSdkVersion="21" android:targetSdkVersion="31" />
    <application android:allowBackup="false" android:icon="@mipmap/appicon" android:exported="false" android:fullBackupContent="false" android:roundIcon="@mipmap/appicon_round" android:supportsRtl="true">
    </application>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
</manifest>

异常信息（中文翻译） #

[monodroid-assembly] 从bundle加载程序集失败：Xamarin.AndroidX.Security.SecurityCrypto.dll
已加载程序集：/data/data/com.abc.mypp.test/files/.__override__/Xamarin.AndroidX.Security.SecurityCrypto.dll [外部]
[AndroidKeysetManager] 未找到密钥集，将生成新密钥集
[AndroidKeysetManager] java.io.FileNotFoundException: 无法读取密钥集；偏好设置值__androidx_security_crypto_encrypted_prefs_key_keyset__不存在
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.SharedPrefKeysetReader.readPref(SharedPrefKeysetReader.java:71)
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.SharedPrefKeysetReader.readEncrypted(SharedPrefKeysetReader.java:89)
[AndroidKeysetManager]  at com.google.crypto.tink.KeysetHandle.read(KeysetHandle.java:116)
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.AndroidKeysetManager$Builder.read(AndroidKeysetManager.java:311)
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.AndroidKeysetManager$Builder.readOrGenerateNewKeyset(AndroidKeysetManager.java:287)
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.AndroidKeysetManager$Builder.build(AndroidKeysetManager.java:238)
[AndroidKeysetManager]  at androidx.security.crypto.EncryptedSharedPreferences.create(EncryptedSharedPreferences.java:155)
[AndroidKeysetManager]  at androidx.security.crypto.EncryptedSharedPreferences.create(EncryptedSharedPreferences.java:120)
[AndroidKeysetManager] 未找到密钥集，将生成新密钥集
[AndroidKeysetManager] java.io.FileNotFoundException: 无法读取密钥集；偏好设置值__androidx_security_crypto_encrypted_prefs_value_keyset__不存在
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.SharedPrefKeysetReader.readPref(SharedPrefKeysetReader.java:71)
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.SharedPrefKeysetReader.readEncrypted(SharedPrefKeysetReader.java:89)
[AndroidKeysetManager]  at com.google.crypto.tink.KeysetHandle.read(KeysetHandle.java:116)
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.AndroidKeysetManager$Builder.read(AndroidKeysetManager.java:311)
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.AndroidKeysetManager$Builder.readOrGenerateNewKeyset(AndroidKeysetManager.java:287)
[AndroidKeysetManager]  at com.google.crypto.tink.integration.android.AndroidKeysetManager$Builder.build(AndroidKeysetManager.java:238)
[AndroidKeysetManager]  at androidx.security.crypto.EncryptedSharedPreferences.create(EncryptedSharedPreferences.java:160)
[AndroidKeysetManager]  at androidx.security.crypto.EncryptedSharedPreferences.create(EncryptedSharedPreferences.java:120)
[EngineFactory] 无法获取GmsCore_OpenSSL提供程序

解决步骤 #

• 检查并更新NuGet包：确保Android项目已安装Xamarin.AndroidX.Security.Crypto包，且版本与其他Xamarin.AndroidX包兼容，建议更新到最新稳定版。
• 清理重建项目：删除Android项目的bin和obj文件夹，清理解决方案后重新生成，解决缓存导致的程序集加载问题。
• 移除不必要的权限：SecureStorage使用应用内部存储，无需READ_EXTERNAL_STORAGE和WRITE_EXTERNAL_STORAGE权限，移除这两项权限避免潜在冲突。
• 安装Google Play Services相关包：针对GmsCore_OpenSSL not available提示，安装Xamarin.GooglePlayServices.Base包，确保加密库依赖正常。
• 验证备份配置：确认android:allowBackup="false"和android:fullBackupContent="false"已正确设置，避免备份机制干扰密钥集生成。

内容的提问来源于stack exchange，提问作者boss