如何实现加密的共享首选项

Question

如何使用https://developer.android.google.cn/reference/androidx/security/crypto/EncryptedSharedPreferences在我的 android java 应用程序中实现加密共享首选项？我不知道如何实施，有人可以帮忙吗？

Answer 1

我使用的代码与 @Chirag 编写的代码类似，但在我对 Android Studio 4.0 项目应用新的更新后，我收到一条警告，表明该类MasterKeys已弃用。

所以我找到了这个答案并且它成功了。这是片段中的代码。如果您想在 MainActivity 中使用它，请更改getContext()为this

 MasterKey getMasterKey() {
    try {
        KeyGenParameterSpec spec = new KeyGenParameterSpec.Builder(
                "_androidx_security_master_key_",
                KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_DECRYPT)
                .setBlockModes(KeyProperties.BLOCK_MODE_GCM)
                .setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_NONE)
                .setKeySize(256)
                .build();

        return new MasterKey.Builder(getContext())
                .setKeyGenParameterSpec(spec)
                .build();
    } catch (Exception e) {
        Log.e(getClass().getSimpleName(), "Error on getting master key", e);
    }
    return null;
}

private SharedPreferences getEncryptedSharedPreferences() {
    try {
        return EncryptedSharedPreferences.create(
                Objects.requireNonNull(getContext()),
                "Your preference file name",
                getMasterKey(), // calling the method above for creating MasterKey
                EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
                EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
        );
    } catch (Exception e) {
        Log.e(getClass().getSimpleName(), "Error on getting encrypted shared preferences", e);
    }
    return null;
}

然后你可以像这样使用上面的内容：

   public void someFunction(){
        SharedPreferences sharedPreferences = getEncryptedSharedPreferences();
        //Used to add new entries and save changes
        SharedPreferences.Editor editor = sharedPreferences.edit();
        
        //To add entry to your shared preferences file
        editor.putString("Name", "Value");
        editor.putBoolean("Name", false);
        //Apply changes and commit
        editor.apply();
        editor.commit();
        
        //To clear all keys from your shared preferences file
        editor.clear().apply();
        
        //To get a value from your shared preferences file
        String returnedValue  = sharedPreferences.getString("Name", "Default value if null is returned or the key doesn't exist");
    }