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在实现播放器的时候，我们需要捕获键盘、鼠标事件进行视频快进、快退，或者双击全屏/退出全屏窗口、鼠标右键弹出菜单栏。默认情况下，在使用libVLC库的时候，我们无法捕获这些事件，因为我们将Qt的视频窗口传递给了libVLC。

libvlc_media_player_set_hwnd(vlc_mediaPlayer, (void *)ui.widgetShow->winId());

但是libVLC提供了两个接口，使得忽略了对鼠标键盘事件的处理，让事件返回到原始Qt的widget上。

	libvlc_video_set_mouse_input(vlc_mediaPlayer, 0);libvlc_video_set_key_input(vlc_mediaPlayer, 0);

好了，知道了如何操作了之后，下面开始实现代码。

首先打开文件的时候禁用鼠标、键盘事件，并且设置视频窗口为Qt的Widget控件，libvlc_media_player_set_hwnd。

void showWidget::slotOpenFile()
{/*选择文件*/QString filename = QFileDialog::getOpenFileName(this, "选择打开的文件", "D:/", tr("*.*"));std::replace(filename.begin(), filename.end(), QChar('/'), QChar('\\'));vlc_base = libvlc_new(0, NULL);vlc_media = libvlc_media_new_path(vlc_base, filename.toUtf8().data());if (!vlc_media) {return;}// 创建libvlc实例和媒体播放器vlc_mediaPlayer = libvlc_media_player_new_from_media(vlc_media);if (!vlc_mediaPlayer) {return;}// 等待元数据加载完成libvlc_media_parse(vlc_media);m_defalutRate = libvlc_video_get_aspect_ratio(vlc_mediaPlayer);m_defalutCrop = libvlc_video_get_crop_geometry(vlc_mediaPlayer);libvlc_video_set_mouse_input(vlc_mediaPlayer, 0);libvlc_video_set_key_input(vlc_mediaPlayer, 0);// 获取各种元数据const char *title = libvlc_media_get_meta(vlc_media, libvlc_meta_Title);const char *artist = libvlc_media_get_meta(vlc_media, libvlc_meta_Artist);const char *album = libvlc_media_get_meta(vlc_media, libvlc_meta_Album);const char *url = libvlc_media_get_meta(vlc_media, libvlc_meta_URL);const char *date = libvlc_media_get_meta(vlc_media, libvlc_meta_Date);const char *lang = libvlc_media_get_meta(vlc_media, libvlc_meta_Language);int duration = libvlc_media_get_duration(vlc_media);  // 获取时长（单位：毫秒）qDebug("Title: %s", title ? title : "N/A");qDebug("Artist: %s", artist ? artist : "N/A");qDebug("Album: %s", album ? album : "N/A");qDebug("Duration: %d ms", duration);qDebug("url: %s", url ? url : "N/A");qDebug("date: %s", date ? date : "N/A");qDebug("lang: %s", lang ? lang : "N/A");libvlc_media_track_t **tracks;int track_count = libvlc_media_tracks_get(vlc_media,&tracks);for (unsigned i = 0; i < track_count; i++) {libvlc_media_track_t* track = tracks[i];// 显示轨道信息printf("Track #%u: %s\n", i, track->psz_description);// 这里可以获取到每一个轨道的信息，比如轨道类型 track->i_type// 可能是 libvlc_track_video, libvlc_track_audio 或者 libvlc_track_text (字幕)if (track->i_type == libvlc_track_video) {// 处理视频轨道信息qDebug("width = %d",track->video->i_width);qDebug("height = %d", track->video->i_height);qDebug("rate_num = %d", track->video->i_frame_rate_num);qDebug("rate_den = %d", track->video->i_frame_rate_den);}else if (track->i_type == libvlc_track_audio) {// 处理音频轨道信息qDebug("channels = %d", track->audio->i_channels);qDebug("rate = %d", track->audio->i_rate);}else if (track->i_type == libvlc_track_text) {// 处理字幕轨道信息}}//获取事件管理器libvlc_event_manager_t *em = libvlc_media_player_event_manager(vlc_mediaPlayer);// 注册事件监听器libvlc_event_attach(em, libvlc_MediaPlayerTimeChanged, vlcEvents, this);libvlc_event_attach(em, libvlc_MediaPlayerEndReached, vlcEvents, this);libvlc_event_attach(em, libvlc_MediaPlayerStopped, vlcEvents, this);libvlc_event_attach(em, libvlc_MediaPlayerPlaying, vlcEvents, this);libvlc_event_attach(em, libvlc_MediaPlayerPaused, vlcEvents, this);libvlc_media_player_set_hwnd(vlc_mediaPlayer, (void *)ui.widgetShow->winId());QTimer::singleShot(1000, this, &showWidget::slotPlay);
}

然后鼠标右键显示菜单：

 代码实现：

	//.hQMenu *m_menu = nullptr;QAction *m_video = nullptr;QAction *m_scaleAction = nullptr;	//缩放QAction *m_aspectRatioAction = nullptr;	//宽高比QAction *m_cropAction = nullptr;	//裁剪QMenu *m_videoMenu = nullptr;//.cpp//总菜单m_menu = new QMenu(this);m_video = m_menu->addAction("视频");//视频菜单m_videoMenu = new QMenu(this);m_scaleAction = m_videoMenu->addAction("缩放");m_aspectRatioAction = m_videoMenu->addAction("宽高比");m_cropAction = m_videoMenu->addAction("裁剪");m_video->setMenu(m_videoMenu);//宽高比菜单m_aspectRatioMenu = new QMenu(this);m_aspectRatioAction->setMenu(m_aspectRatioMenu);

重写鼠标和键盘事件。

protected:virtual void mousePressEvent(QMouseEvent *event);virtual void mouseDoubleClickEvent(QMouseEvent *event);virtual void keyPressEvent(QKeyEvent *event);

鼠标双击全屏。

void showWidget::mouseDoubleClickEvent(QMouseEvent *event)
{if (this->isFullScreen()){this->showNormal();}else{this->showFullScreen();}
}

键盘事件：调节W、S键音量大小和space键暂停和播放。

void showWidget::keyPressEvent(QKeyEvent *event)
{if (!vlc_mediaPlayer)return;int value = ui.hSliderVolumn->value();if (event->key() == Qt::Key_W)	//添加音量{qDebug() << "up";slotValueChanged(value+10);}else if (event->key() == Qt::Key_S)	//减小音量{slotValueChanged(value - 10);}else if (event->key() == Qt::Key_Space){if (vlc_mediaPlayer && libvlc_media_player_get_state(vlc_mediaPlayer) == libvlc_Playing){libvlc_media_player_pause(vlc_mediaPlayer);}else if (vlc_mediaPlayer && libvlc_media_player_get_state(vlc_mediaPlayer) == libvlc_Paused){libvlc_media_player_play(vlc_mediaPlayer);}}
}void showWidget::slotValueChanged(int value)
{if (vlc_mediaPlayer)libvlc_audio_set_volume(vlc_mediaPlayer, value);
}

鼠标点击弹出菜单。

void showWidget::mousePressEvent(QMouseEvent *event)
{switch (event->button()){case Qt::RightButton://this->setWindowState(Qt::WindowMinimized);m_menu->exec(event->globalPos());break;default:QWidget::mousePressEvent(event);}
}

更多参考：

libVLC 事件机制-CSDN博客

libVLC windows开发环境搭建-CSDN博客

https://sunnnnnn666.blog.csdn.net/article/details/136854500

libVLC 元数据-CSDN博客

libVLC 添加图片和文本水印-CSDN博客

https://sunnnnnn666.blog.csdn.net/article/details/136920169

https://sunnnnnn666.blog.csdn.net/article/details/137023036