SharedPreferencesManager

Simplifies use of Android's SharedPreferences and allows storing of custom objects and list of objects.

How does it work?

1. Create an instance of Android's SharedPreferences

val sharedPreferences = applicationContext.getSharedPreferences("myCustomFileName", Context.MODE_PRIVATE)

1. Create an instance of SharedPreferencesManager with it.

preferencesManager = SharedPreferencesManager(sharedPreferences)

or if you require more options, you could do something like

preferencesManager = SharedPreferencesManager(
    sharedPreferences = sharedPreferences
    json = Json { isLenient = true },
    errorListener = { it.printStackTrace() }
)

additionally, you can use provided InMemorySharedPreferences. This will persist all data in memory only and omit using files. Useful for testing without mocking the context or if there is no need to persist data outside of application lifecycle.

val sharedPreferences = InMemorySharedPreferences()

2. Use any of the public methods to retrieve or save data. Any put call automatically applies changes.

fun getBoolean(key: String, defaultValue: Boolean): Boolean
fun setBoolean(key: String, value: Boolean)
fun getFloat(key: String, defaultValue: Float = 0f): Float
fun setFloat(key: String, value: Float)
fun getInt(key: String, defaultValue: Int = 0): Int
fun setInt(key: String, value: Int)
fun getList(key: String, defaultValue: List<T>? = null): List<T>?
fun getListAsync(key: String, defaultValue: T? = null, callback: (List<T>?) -> Unit)
fun setList(key: String, list: List<T>?)
fun setListAsync(key: String, list: List<T>?, callback: () -> Unit)
fun getLong(key: String, defaultValue: Long = 0L): Long
fun setLong(key: String, value: Long)
fun getObject(key: String, defaultValue: T? = null) : T?
fun getObjectAsync(key: String, defaultValue: T? = null, callback: (T?) -> Unit)
fun setObject(key: String, obj: T?)
fun setObjectAsync(key: String, obj: T?, callback: () -> Unit)
fun getString(key: String, defaultValue: String?): String?
fun setString(key: String, value: String?)
fun getStringSet(key: String, defaultValue: MutableSet<String>?): MutableSet<String>?
fun setStringSet(key: String, value: MutableSet<String>?)
fun clearData()
fun getAll(): MutableMap<String, *>?
fun remove(key: String)

Note that getObject, putObject, getList and putList use Kotlin serialization, so T has to be annotated as Serializable, otherwise SerializationException will be thrown.

Known objects or list of objects are cached in memory to avoid redundant deserialization:

• Edit to object or list of objects will update the cache.
• Retrieving object or list of objects will retrieve the cached copy if it exists.
• for other functions, SharedPreferences uses in-memory caching for known values.

Nice! How do I get started?

Make sure root build.gradle repositories include JitPack

allprojects {
    repositories {
        maven { url 'https://jitpack.io' }
    }
}

And SharedPreferencesManager dependency is added to app build.gradle

dependencies {
    implementation 'com.github.mvojtkovszky:SharedPreferencesManager:$latest_version'
}