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Welcome to ⚓️ anchor

Anchor is simple and extensible state management architecture built on Kotlin's Context receivers with Jetpack Compose integration.

Goal

Focus on writing an amazing app and let Anchor handle the rest!

Installation

Follow the Github Packages guide to use a published package from the github packages repository.

  1. Generate a classic token with read:packages access with the help of Github guide

  2. Add the repository to your build.gradle.kts file

    repositories {
  maven {
    url = uri("https://maven.pkg.github.com/kioba/anchor")
    credentials {
      username = project.findProperty("gpr.user") as String? ?: System.getenv("USERNAME")
      password = project.findProperty("gpr.key") as String? ?: System.getenv("TOKEN")
    }
  }
}

  3. Add the package dependencies to your build.gradle.kts file

    implementation("dev.kioba:anchor:0.0.8")

Counter example

Counter example to showcase the usage of Anchor architecture. The screen displays a count and the ability to increment and decrement the count.

counter example

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// viewState to represent the state of screen
data class CounterState(
  val count: Int = 0,
) : ViewState

// type alias to easily reference our Scope without repeating the type arguments
typealias CounterAnchor = Anchor<EmptyEffect, CounterState>

// function to generate the Scope with the initial state
fun RememberAnchorScope.counterAnchor(): CounterAnchor =
  create(
    initialState = ::CounterState,
    effectScope = { EmptyEffect },
  )

// Provide the Anchor abilities with a captured receiver
fun CounterAnchor.increment() {
  // modify the view state by incrementing the state value
  reduce { copy(count = count.inc()) }
}

@Composable
fun CounterUi() {
  // Scope computations are remembered and retained across configuration changes
  RememberAnchor(RememberAnchorScope::counterAnchor) { state ->
    Button(
      // within a RememberAnchor actions can be executed
      // without the requirement to pass around the scope
      onClick = anchor<CounterAnchor> { increment() },
    ) { IncrementIcon() }
  }
}

ViewModel

Storing Anchor within a ViewModel is not required manually. RememberAnchor takes care of handling the storage within a dedicated ViewModel.

Configuration changes and process death

TBD

ViewState

TBD

License

Copyright 2025 Karoly Somodi

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.