Popalay / workflow-kotlin-compose

Jetpack Compose integration for Square Workflows.

workflow-kotlin-compose

This module provides experimental support for Jetpack Compose UI with workflows.

The only integration that is currently supported is the ability to define ViewFactories that are implemented as @Composable functions. See the hello-compose-binding sample in samples for an example of how to use.

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Pre-Alpha

DO NOT USE this module in your production apps!

Jetpack Compose is in pre-alpha, developer preview stage. The API is incomplete and changes very frequently. This integration module exists as a proof-of-concept, to show what's possible, and to experiment with various ways to integrate Compose with Workflow.

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Usage

Add the dependency

Add the dependencies from this project (they're on Maven Central):

dependencies {
  // Main dependency
  implementation "com.squareup.workflow:workflow-ui-core-compose:${versions.workflow_compose}"

  // For the preview helpers
  implementation "com.squareup.workflow:workflow-ui-compose-tooling:${versions.workflow_compose}"
}

Enable Compose

You must be using the latest Android Gradle Plugin 4.x version, and enable Compose support in your build.gradle:

android {
  buildFeatures {
    compose true
  }
  composeOptions {
    kotlinCompilerVersion "1.3.70-dev-withExperimentalGoogleExtensions-20200424"
    kotlinCompilerExtensionVersion "${compose_version}"
  }
}

You may also need to set the Kotlin API version to 1.3:

tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).configureEach {
  kotlinOptions.apiVersion = "1.3"
}

To create a ViewFactory, call composedViewFactory. The lambda passed to composedViewFactory is a @Composable function.

val HelloBinding = composedViewFactory<MyRendering> { rendering, _ ->
  MaterialTheme {
    Clickable(onClick = { rendering.onClick() }) {
      Text(rendering.message)
    }
  }
}

The composedViewFactory function returns a regular ViewFactory which can be added to a ViewRegistry like any other:

val viewRegistry = ViewRegistry(HelloBinding)