HarmonyOSAndroidiOSmacOSWebC++ (全平台)HarmonyOSC# (Windows)小程序ElectronUnityFlutterReact NativeUnreal (C++)Unreal (Blueprint)React文档中心/实时互动/本页总览MediaPlayerPreloadEventv4.4.2v4.4.2v4.4.1v4.4.0MediaPlayerPreloadEvent预加载媒体资源时发生的事件。枚举值PLAYER_PRELOAD_EVENT_BEGIN 0: 开始预加载媒体资源。PLAYER_PRELOAD_EVENT_COMPLETE 1: 预加载媒体资源完成。PLAYER_PRELOAD_EVENT_ERROR 2: 预加载媒体资源出错。