PrefeRx

This is a reactive SharedPreferences library for Kotlin

• allows to integrate & manage your preferences with RxJava
• easily stores primitives, enums and other serializable objects

Download

dependencies {
  implementation 'com.vinted:preferx:<version>'
}

Supported types

Library supports default SharedPreferences types with default fallback values when preference was not yet set or was cleared.

  sharedPreferences.intPreference("counter", 0)

  sharedPreferences.stringPreference("string", "")

  sharedPreferences.booleanPreference("seen", false)

  sharedPreferences.longPreference("timestamp", 0L)

It also allows easy storing of enums and objects.

  sharedPreferences.enumPreference("notifications", Frequency.ALL)

  sharedPreferences.objectPreference(
    name = "current_user"
    defaultValue = User.ANONYMOUS,
    serializer = someSerializer,
    clazz = User::class
  )

Basic example

class ExampleActivity : Activity {

  private val sharedPreferences by lazy {
    getSharedPreferences("app-pref", Context.MODE_PRIVATE)
  }

  private val sessionCounter : IntPreference by lazy {
    sharedPreferences.intPreference("counter", 0)
  }

  @Override
  public fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.simple_activity)

    val incrementedCount = sessionCounter.get() + 1
    sessionCounter.set(incrementedCount)

    counter_view.text = "Application was started $incrementedCount times"
  }
}

RxJava example

class ExampleActivity : Activity {

  ...

  private var disposable: Disposable? = null

  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    Observable.just(stringPreference.get())
      .concatWith(stringPreference.onChangeObservable)
      .subscribe {
          text_view.text = it
      }
    }.apply { disposable = this }
  }

  override fun onDestroy() {
    disposable?.dispose()
    super.onDestroy()
  }

  ...
}

For more usage examples see:

• preferences with dagger
• preferences in Rx stream

Caveats

• When EnumSerializer fails to resolve enum value for any reason it will fallback to default value
• When using EntitySerializer one must ensure that it returns value. In case of null it will fallback to default value.

License

MIT License

Copyright (c) 2021 Vinted UAB

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.