A class that is using the “normal” shared preferences for any device with an sdk < M and the EncryptedSharedPreferences for M and above.
Usage
Gradle dependency:
implementation "androidx.security:security-crypto:$security_version"
``
Sample usage using Koin DI, inside an Activity:
```kotlin
private val appModule = module {
single {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
EncryptedSharedPrefs(applicationContext)
} else
SimplePreferences(applicationContext)
}
}
override fun onCreate() {
super.onCreate()
startKoin {
androidLogger()
androidContext(this@App)
modules(appModule)
}
}
Usage:
class MyFragment : Fragment(R.layout.fragment_my) {
private val preferences: Preferences by inject()
...
preferences.mySetting = false
}
AndroidManifest.xml
If the min SDK is smaller than 27, this line should be added in the Manifest:
<uses-sdk tools:overrideLibrary="androidx.security" />
Preferences.kt
interface Preferences {
var mySetting: Boolean
fun get(): SharedPreferences
}
class SimplePreferences(context: Context) : Preferences {
private val preferences: SharedPreferences =
context.getSharedPreferences("myapp_preferences", Context.MODE_PRIVATE)
override fun get(): SharedPreferences = preferences
override var mySetting: Boolean
get() = preferences.getBoolean(App.MY_SETTING_PREF_KEY, true)
set(value) = preferences.edit().putBoolean(App.MY_SETTING_PREF_KEY, value).apply()
}
@TargetApi(Build.VERSION_CODES.M)
class EncryptedSharedPrefs(val context: Context) : Preferences {
private var encryptedPrefs: SharedPreferences = EncryptedSharedPreferences.create(
"myapp_encrypted_prefs",
MasterKeys.getOrCreate(MasterKeys.AES256_GCM_SPEC),
context,
EncryptedSharedPreferences.PrefKeyEncryptionScheme.AES256_SIV,
EncryptedSharedPreferences.PrefValueEncryptionScheme.AES256_GCM
)
override fun get(): SharedPreferences = encryptedPrefs
// A shortcut property to access data stored in the prefs in a consistent way
override var mySetting: Boolean
get() = encryptedPrefs.getBoolean(App.MY_SETTING_PREF_KEY, null)
set(value) = encryptedPrefs.edit().putBoolean(
App.MY_SETTING_PREF_KEY,
value
)
}