UI framework combining MVI, MVVM, and SAM principles. Simplifies business logic encapsulation, supports various programming styles, ensures predictability, and offers composability for complex applications.
Kotlin Bloc is a Multiplatform UI framework combining the best of MVI, MVVM and SAM. It's
Bloc (Business Logic Component) encapsulates the application's business logic. It receives from the view, processes those actions and outputs and optionally .Note, this readme offers a quick overview of the framework. For more in-depth information consult:
dependencies {
// the core library
implementation("com.1gravity:bloc-core:0.11.0")
// add to use the framework together with Redux
implementation("com.1gravity:bloc-redux:0.11.0")
// useful extensions for Android and Jetpack/JetBrains Compose
implementation("com.1gravity:bloc-compose:0.11.0")
}
The "Hello World" example of UI frameworks is the counter app. Creating the "business logic" part of such an app is very simple with Kotlin Bloc:
fun bloc(context: BlocContext) = bloc<Int, Int>(context, 1) {
reduce { state + action }
}
The view part is very simple too.
class CounterActivity : AppCompatActivity() {
// create or retrieve the lifecycle aware Bloc
private val bloc by getOrCreate { bloc(it) }
setContent {
// observe the Bloc state
val state by bloc.observeState()
// updates on state / count changes
Text("Counter: $state")
// emit events / actions to update the state / count
Button(onClick = { bloc.send(1) }, content = { Text("Increment") })
Button(onClick = { bloc.send(-1) }, content = { Text("Decrement") })
}
Note: the Bloc is lifecycle aware and will survive configuration changes (no ViewModel needed...).
On iOS there's a bit more boilerplate code (BlocHolder and BlocObserver are omitted here) but it's still pretty "lean":
// iOS
struct CounterView: View {
// create the lifecycle aware Bloc
private let holder { .bloc(context: ) }
model: <, , >
() {
model (holder.value)
}
var body: some View {
return VStack() {
// updates on state / count changes
Text("Counter \(model.value)")
// emit events / actions to update the state / count
(
action: { holder.value.send(value: ) },
label: { () }
)
(
action: { holder.value.send(value: ) },
label: { () }
)
Kotlin Bloc supports different MVI/MVVM "styles". The example above shows one of many ways to implement the counter app. In the official documentation you'll find more example to demonstrate:
Copyright 2022 Emanuel Moecklin
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance the License.
You may obtain a copy of the License at
http:
Unless applicable law agreed to writing, software
distributed under the License distributed an BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express implied.
See the License the specific language governing permissions
limitations under the License.
Action(s)ProposalsSideEffect(s)BlocState holds the component's State. It's separate from the actual Bloc to support different scenarios like:
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