KMP纯桌面项目本地视频播放方案咨询，JavaFX集成遇阻

方案一：修复JavaFX集成问题 #

多数集成失败是因为KMP桌面模块的配置疏漏，按以下步骤重新配置：

1. 桌面模块build.gradle.kts配置
   添加JavaFX插件与依赖，指定兼容的JVM版本：

   plugins {
       kotlin("multiplatform")
       id("org.openjfx.javafxplugin") version "0.0.13"
   }
   
   kotlin {
       jvm("desktop") {
           compilations.all {
               kotlinOptions.jvmTarget = "17"
           }
           withJava()
       }
       sourceSets {
           val desktopMain by getting {
               dependencies {
                   implementation("org.openjfx:javafx-controls:21")
                   implementation("org.openjfx:javafx-media:21")
               }
           }
       }
   }
   
   javafx {
       version = "21"
       modules = listOf("javafx.controls", "javafx.media")
   }
   

2. 编写视频播放代码
   在桌面模块主类中，用JavaFX原生的MediaPlayer实现播放：

   import javafx.application.Application
   import javafx.scene.Scene
   import javafx.scene.layout.StackPane
   import javafx.scene.media.Media
   import javafx.scene.media.MediaPlayer
   import javafx.scene.media.MediaView
   import javafx.stage.Stage
   import java.io.File
   
   class VideoPlayerApp : Application() {
       override fun start(primaryStage: Stage) {
           val videoFile = File("path/to/your/local/video.mp4")
           val media = Media(videoFile.toURI().toString())
           val mediaPlayer = MediaPlayer(media)
           val mediaView = MediaView(mediaPlayer)
   
           val root = StackPane(mediaView)
           primaryStage.scene = Scene(root, 800.0, 600.0)
           primaryStage.show()
   
           mediaPlayer.play()
       }
   }
   
   fun main() {
       Application.launch(VideoPlayerApp::class.java)
   }
   

   注意：JavaFX原生支持MP4（H.264编码）、MKV等格式，若视频格式不兼容，可先转码后再播放。

方案二：使用JavaCV（基于FFmpeg） #

如果JavaFX格式支持有限，或仍存在集成问题，JavaCV是更灵活的选择——它封装了FFmpeg，支持几乎所有本地视频格式：

1. 桌面模块build.gradle.kts配置

   kotlin {
       jvm("desktop") {
           // 保留原有JVM配置
       }
       sourceSets {
           val desktopMain by getting {
               dependencies {
                   implementation("org.bytedeco:javacv-platform:1.5.9")
               }
           }
       }
   }
   

2. 编写播放代码

   import org.bytedeco.javacv.CanvasFrame
   import org.bytedeco.javacv.FFmpegFrameGrabber
   import org.bytedeco.javacv.Frame
   import org.bytedeco.javacv.FrameConverter
   import java.awt.Dimension
   
   fun playLocalVideo(videoPath: String) {
       val grabber = FFmpegFrameGrabber(videoPath).apply { start() }
       val canvas = CanvasFrame("Local Video Player").apply {
           isVisible = true
           preferredSize = Dimension(grabber.imageWidth, grabber.imageHeight)
       }
   
       val converter = FrameConverter.ToBufferedImage()
       var frame: Frame?
       while (canvas.isVisible && grabber.grab().also { frame = it } != null) {
           canvas.showImage(converter.convert(frame))
       }
   
       grabber.stop()
       grabber.release()
       canvas.dispose()
   }
   
   fun main() {
       playLocalVideo("path/to/your/local/video.mp4")
   }
   

   该方案无需依赖JavaFX UI，直接使用AWT的CanvasFrame，KMP桌面模块原生兼容AWT。

方案三：使用LibGDX桌面模块 #

若项目需要复杂交互或游戏类UI，LibGDX桌面模块可与KMP无缝集成，且原生支持视频播放：

1. 桌面模块build.gradle.kts配置

   val gdxVersion = "1.12.1"
   kotlin {
       jvm("desktop") {
           // 保留原有JVM配置
       }
       sourceSets {
           val desktopMain by getting {
               dependencies {
                   implementation("com.badlogicgames.gdx:gdx:$gdxVersion")
                   implementation("com.badlogicgames.gdx:gdx-backend-lwjgl3:$gdxVersion")
                   implementation("com.badlogicgames.gdx:gdx-video:$gdxVersion")
               }
           }
       }
   }
   

2. 编写播放代码

   import com.badlogic.gdx.ApplicationAdapter
   import com.badlogic.gdx.Gdx
   import com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application
   import com.badlogic.gdx.backends.lwjgl3.Lwjgl3ApplicationConfiguration
   import com.badlogic.gdx.graphics.g2d.SpriteBatch
   import com.badlogic.gdx.video.VideoPlayer
   import com.badlogic.gdx.video.VideoPlayerCreator
   
   class VideoPlayerGame : ApplicationAdapter() {
       private lateinit var batch: SpriteBatch
       private lateinit var videoPlayer: VideoPlayer
   
       override fun create() {
           batch = SpriteBatch()
           videoPlayer = VideoPlayerCreator.createVideoPlayer()
           val videoFile = Gdx.files.absolute("path/to/your/local/video.mp4")
           videoPlayer.play(videoFile)
       }
   
       override fun render() {
           batch.begin()
           videoPlayer.render(batch)
           batch.end()
       }
   
       override fun dispose() {
           batch.dispose()
           videoPlayer.dispose()
       }
   }
   
   fun main() {
       val config = Lwjgl3ApplicationConfiguration().apply {
           setTitle("LibGDX Video Player")
           setWindowedMode(800, 600)
       }
       Lwjgl3Application(VideoPlayerGame(), config)
   }
   

内容的提问来源于stack exchange，提问作者Bojann