How to configure the javafx plugin in a custom gradle plugin? - kotlin

Question

I am new to gradle. I am working on a kotlin library that requires JavaFX. I wanted to use gradle to manage my dependencies and make it easier to include my library in a new project.
My library project applies and configures the javafx plugin and its build file looks like this (kotlin dsl):
plugins {
`java-library`
id("org.openjfx.javafxplugin")
}
group = "me.shai"
version = "1.0"
javafx {
version = "15.0.1"
modules = listOf("javafx.controls", "javafx.fxml")
}
dependencies {
// Other dependencies
testImplementation(kotlin("test-junit5"))
testImplementation("org.junit.jupiter:junit-jupiter-api:5.6.0")
testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.6.0")
}
tasks.test {
useJUnitPlatform()
}
kotlin {
explicitApi()
}
Apparently, a project that wants to use my library also has to apply and configure JavaFX. Here's an example for a build file of a demo project that consumes my library:
plugins {
id("org.openjfx.javafxplugin")
}
group = "me.shai"
version = "1.0"
javafx {
version = "15.0.1"
modules = listOf("javafx.controls", "javafx.fxml")
}
dependencies {
implementation(project(":MyLib")) // Pretend the library is published so we use a url instead of local project
}
This is slightly annoying, so I decided to do something similar to JavaFX: write a custom plugin to include my project. The plugin needs to:
Add my library as a dependency
Apply the JavaFX plugin
Configure the JavaFX plugin
I managed to achieve steps 1 and 2, but I am stuck at step 3. How can I configure the JavaFX plugin from a custom plugin kotlin class?
Here's what I have so far:
package mylib.gradle
import org.gradle.api.Plugin
import org.gradle.api.Project
import org.gradle.api.artifacts.DependencyResolutionListener
import org.gradle.api.artifacts.ResolvableDependencies
import org.gradle.kotlin.dsl.project
class MyLibPlugin : Plugin<Project> {
override fun apply(project: Project) {
// Apply the javafx plugin
project.plugins.apply("org.openjfx.javafxplugin")
// How to configure javafx here?
val implementationDeps = project.configurations.getByName("implementation").dependencies
project.gradle.addListener(object : DependencyResolutionListener {
override fun beforeResolve(dependencies: ResolvableDependencies) {
// Add dependency on my library project.
implementationDeps.add(project.dependencies.project(":MyLib"))
project.gradle.removeListener(this)
}
override fun afterResolve(dependencies: ResolvableDependencies) {}
})
}
}
I am basically trying to write the equivalent of the build script block:
javafx {
version = "15.0.1"
modules = listOf("javafx.controls", "javafx.fxml")
}
And I can't figure out how to achieve this. I'd appreciate any help on the subject.

Answer 1

You would configure the javafx extension just as you would in the build file:
// build.gradle[.kts]
dependencies {
implementation("org.openjfx:javafx-plugin:0.0.10")
}
And the plugin implementation:
import org.gradle.api.Plugin
import org.gradle.api.Project
import org.gradle.api.plugins.JavaPlugin
import org.openjfx.gradle.JavaFXOptions
open class MyLibPlugin : Plugin<Project> {
override fun apply(project: Project) {
project.pluginManager.apply("org.openjfx.javafxplugin")
val myLibDependency = project.dependencies.project(mapOf("path" to ":MyLib"))
project.dependencies.add(JavaPlugin.IMPLEMENTATION_CONFIGURATION_NAME, myLibDependency)
project.extensions.configure(JavaFXOptions::class.java) {
it.version = "15.0.1"
it.modules = listOf("javafx.controls", "javafx.fxml")
}
}
}