Desktop Web View

build.gradle.kts

plugins {
    kotlin("multiplatform")
    id("org.openjfx.javafxplugin") version "0.0.10"
}

kotlin {
    jvm("desktop") {
        compilations.all {
            kotlinOptions {
                jvmTarget = "11"
            }
            withJava()
        }
    }

    sourceSets {
        val desktopMain by getting {
            dependencies {
                implementation(compose.desktop.currentOs)
                //Optional other deps
                implementation(compose.uiTooling)
                implementation(compose.runtime)
                implementation(compose.foundation)
                implementation(compose.material)
                implementation(compose.animation)
                implementation(compose.animationGraphics)
            }
        }
    }
}

javafx {
    version = "17"
    modules = listOf("javafx.controls", "javafx.swing", "javafx.web", "javafx.graphics")
}

DesktopWebView.kt

@Composable
fun DesktopWebView() {
    val finishListener = object : PlatformImpl.FinishListener {
        override fun idle(implicitExit: Boolean) {}
        override fun exitCalled() {}
    }
    PlatformImpl.addListener(finishListener)

    println("Desktop Web View start")
    Window(
        title = "Web View Test",
        resizable = false,
        state = WindowState(
            placement = WindowPlacement.Floating,
            size = DpSize(400.dp, 400.dp)
        ),
        onCloseRequest = {
            PlatformImpl.removeListener(finishListener)
        },
        content = {
            val jfxPanel = remember { JFXPanel() }
            Box(modifier = Modifier.fillMaxSize()) {
                ComposeJFXPanel(
                    composeWindow = window,
                    jfxPanel = jfxPanel,
                    onCreate = {
                        Platform.runLater {
                            val root = WebView()
                            val engine = root.engine
                            val scene = Scene(root)
                            engine.loadWorker.stateProperty().addListener { _, _, newState ->
                                if (newState === Worker.State.SUCCEEDED) {
                                    println("State ${newState.name}")
                                }
                            }
                            engine.loadWorker.exceptionProperty().addListener { _, _, newError ->
                                println("page load error : $newError")
                            }
                            jfxPanel.scene = scene
                            engine.load("http://google.com") // can be a html document from resources ..
                            engine.setOnError { error -> println("onError : $error") }
                        }
                    }, onDestroy = {
                        Platform.runLater {

                        }
                    }
                )
            }
        }
    )
}

@Composable
fun ComposeJFXPanel(
    composeWindow: ComposeWindow,
    jfxPanel: JFXPanel,
    onCreate: () -> Unit,
    onDestroy: () -> Unit = {}
) {
    val jPanel = remember { JPanel() }
    val density = LocalDensity.current.density

    Layout(
        content = {},
        modifier = Modifier.onGloballyPositioned { childCoordinates ->
            childCoordinates.parentCoordinates?.let { layoutCoordinates ->
                val location = layoutCoordinates.localToWindow(Offset.Zero).round()
                val size = layoutCoordinates.size
                jPanel.setBounds(
                    (location.x / density).toInt(),
                    (location.y / density).toInt(),
                    (size.width / density).toInt(),
                    (size.height / density).toInt()
                )
                jPanel.validate()
                jPanel.repaint()
            }
        },
        measurePolicy = { _, _ -> layout(0,0) {} }
    )

    DisposableEffect(jPanel) {
        composeWindow.add(jPanel)
        jPanel.layout = BorderLayout(0, 0)
        jPanel.add(jfxPanel)
        onCreate()
        onDispose {
            onDestroy()
            composeWindow.remove(jPanel)
        }
    }
}