Using encryptedsharedpreferences

build.gradle

android{
  //...
 defaultConfig {
        minSdkVersion 23 // important
        targetSdkVersion 30
        //...
    }

    dependencies{
        implementation "androidx.security:security-crypto:1.1.0-alpha03"
    }
}

sharedprefs.java

import android.security.keystore.KeyGenParameterSpec;
import android.security.keystore.KeyProperties;

import androidx.security.crypto.EncryptedSharedPreferences;
import androidx.security.crypto.MasterKey;


class Foo{
      public void initInstance(BinaryMessenger messenger, Context context) {
            MasterKey key = new MasterKey.Builder(context)
                    .setKeyGenParameterSpec(
                            new KeyGenParameterSpec
                                    .Builder(MasterKey.DEFAULT_MASTER_KEY_ALIAS, KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_DECRYPT)
                                    .setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_NONE)
                                    .setBlockModes(KeyProperties.BLOCK_MODE_GCM)
                                    .setKeySize(256).build())
                    .build();
            preferences = EncryptedSharedPreferences.create(context, "SHARED_PREFERENCES_NAME", key, EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
                    EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM);
    }
}