Shared preferences are a simple key-value storage mechanism that can be used to store small amounts of data. However, since shared preferences are stored in plain text, it is not suitable for storing sensitive information. To address this issue, you can use AES encryption to encrypt the data before saving it to shared preferences.
To use shared preferences with AES encryption support, you can add this package to your project as dependency.
void main() async {
final key = "";
await EncryptedSharedPreferences.initialize(key: key);
var sharedPref = EncryptedSharedPreferences.getInstance();
await sharedPref.setString(
'user_token', 'xxxxxxxxxxxx', notify: true); ////notify = true by default
sharedPref.getString('user_token'); //xxxxxxxxxxxx
await sharedPref.setInt('age', 99, notify: true); //notify = true by default
sharedPref.getInt('age', defaultValue: 1001); //99
await sharedPref.setDouble('pi', 3.14, notify: true); //notify = true by default
sharedPref.getDouble('pi'); //3.14
await sharedPref.setBoolean('isPremium', true, notify: true); //notify = true by default
sharedPref.getBoolean('isPremium'); //true
await sharedPref.remove('user_token', notify: true); //notify = true by default
await sharedPref.clear(notify: true); //notify = true by default
await sharedPref.reload();
final badKeys = {
"key1"
"key2"
};
await sharedPref.removeWhere((key, value) => badKeys.contains(key),
notifyEach: true); //notifyEach:true for notifying for each key update
sharedPref.observe(key: 'token').listen((event) {
// event = key
print(event);
});
sharedPref.observeSet(keys: {'key1', 'key2', 'keyN'}).listen((event) {
// event = key
print(event);
});
}
[Shared builder] Here is example of how to use SharedBuilder widget
class _MyAppState extends State<MyApp> {
@override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
body: SharedBuilder(
listenKeys: const {"key1", "key2"}, //Optional
builder: (EncryptedSharedPreferences encryptedSharedPreferences,String? updatedKey) {
return Text("value : ${encryptedSharedPreferences.getString("key1")}");
},
),
floatingActionButton: FloatingActionButton(
onPressed: () async {
EncryptedSharedPreferences.getInstance()
.setString('key1', 'dataValue');
Future.delayed(const Duration(seconds: 3), () {
EncryptedSharedPreferences.getInstance()
.setString('key2', 'dataValue');
});
},
),
),
);
}
}
Also you can add custom external encryptor
class CustomEncryptor extends IEncryptor {
@override
String decrypt(String key, String encryptedData) {
//decryption logic
}
@override
String encrypt(String key, String plainText) {
//encryption logic
}
}
void main() {
final key = "";
await EncryptedSharedPreferences.initialize(key: key, encryptor: CustomEncryptor());
var sharedPref = EncryptedSharedPreferences.getInstance();
}
Save using batch(Experimental)
await EncryptedSharedPreferences.getInstance().batch((batch) async {
//await all async preference operations
await batch.setString('dataKey1', 'dataValue1');
await batch.setString('dataKey2', 'dataValue2');
await batch.setString('dataKey3', 'dataValue3');
return Future(() => true);
});