以下是一个基于Qt实现的视频播放器的完整源码：
#include <QMediaPlayer>#include <QMediaPlaylist>#include <QVideoWidget>#include <QFileDialog>#include <QVBoxLayout>#include <QHBoxLayout>#include <QPushButton>#include <QSlider>#include <QLabel>#include <QFileIconProvider>#include <QMessageBox>#include <QFileInfo>#include <QDebug>#include <QApplication>class VideoPlayer : public QWidget{Q_OBJECTpublic:VideoPlayer(QWidget *parent = nullptr): QWidget(parent){// 创建媒体播放器和视频展示窗口mediaPlayer = new QMediaPlayer(this);videoWidget = new QVideoWidget(this);mediaPlayer->setVideoOutput(videoWidget);// 创建播放列表playlist = new QMediaPlaylist(this);mediaPlayer->setPlaylist(playlist);// 创建控制按钮playButton = new QPushButton(this);playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));connect(playButton, &QPushButton::clicked, this, &VideoPlayer::togglePlayback);stopButton = new QPushButton(this);stopButton->setIcon(style()->standardIcon(QStyle::SP_MediaStop));connect(stopButton, &QPushButton::clicked, mediaPlayer, &QMediaPlayer::stop);// 创建进度条positionSlider = new QSlider(Qt::Horizontal, this);positionSlider->setRange(0, 0);connect(positionSlider, &QSlider::sliderMoved, this, &VideoPlayer::setPosition);// 创建标签显示视频信息infoLabel = new QLabel(this);infoLabel->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Maximum);// 创建布局QVBoxLayout *mainLayout = new QVBoxLayout;QHBoxLayout *controlLayout = new QHBoxLayout;controlLayout->addWidget(playButton);controlLayout->addWidget(stopButton);controlLayout->addWidget(positionSlider);mainLayout->addWidget(videoWidget);mainLayout->addWidget(infoLabel);mainLayout->addLayout(controlLayout);setLayout(mainLayout);}private slots:void openFile(){QStringList fileNames = QFileDialog::getOpenFileNames(this, "选择视频文件", QString(), "视频文件 (*.mp4 *.avi)");if (!fileNames.isEmpty()) {foreach(const QString &fileName, fileNames) {QFileInfo fileInfo(fileName);if (fileInfo.exists() && fileInfo.isFile()) {playlist->addMedia(QUrl::fromLocalFile(fileName));} else {QMessageBox::warning(this, "错误", QString("无法打开文件: %1").arg(fileName));}}mediaPlayer->play();}}void togglePlayback(){if (mediaPlayer->state() == QMediaPlayer::PlayingState) {mediaPlayer->pause();} else {mediaPlayer->play();}}void setPosition(int position){mediaPlayer->setPosition(position);}void updatePosition(qint64 position){positionSlider->setValue(position);}void updateDuration(qint64 duration){positionSlider->setRange(0, duration);}void handleError(){QMessageBox::critical(this, "错误", QString("发生错误: %1").arg(mediaPlayer->errorString()));}private:QMediaPlayer *mediaPlayer;QVideoWidget *videoWidget;QMediaPlaylist *playlist;QPushButton *playButton;QPushButton *stopButton;QSlider *positionSlider;QLabel *infoLabel;};int main(int argc, char *argv[]){QApplication app(argc, argv);VideoPlayer player;player.setWindowTitle("视频播放器");player.resize(640, 480);player.show();return app.exec();}#include "main.moc"该视频播放器使用了QMediaPlayer、QMediaPlaylist和QVideoWidget等Qt类来实现视频播放功能。界面上有一个视频展示窗口、播放按钮、停止按钮和进度条。用户可以通过点击播放按钮来开始/暂停视频播放，通过点击停止按钮来停止视频播放，通过拖动进度条来调整视频播放位置。
使用方法：
在Qt项目中添加以上源码，例如将其保存为main.cpp。
编译并运行项目。
注意：这段代码使用的是Qt 5的C++ API，可能需要根据您的Qt版本进行适当调整。
