在linux下QT设计实现视频播放器

痛定思痛。 2022-12-27 02:25 222阅读 0赞

通过QT对mplayer的应用，实现视频播放器的功能，包括开始播放、暂停播放、继续播放、终止播放、播放上一个、播放下一个、添加指定目录下的视频、删除指定视频、清空列表。应用到multimedia、multimediawidgets库和QStringList、QFileDialog等类。

界面效果如下：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MzE4MQ_size_16_color_FFFFFF_t_70]

videoplayer.h

#ifndef VIDEOPLAYER_H
    #define VIDEOPLAYER_H
    
    #include <QMainWindow>
    #include <QMediaPlayer>
    #include <QMediaPlaylist>
    #include <QListWidgetItem>
    #include <QVideoWidget>
    #include "myvideowidget.h"
    
    QT_BEGIN_NAMESPACE
    namespace Ui {  class VideoPlayer; }
    QT_END_NAMESPACE
    
    class VideoPlayer : public QMainWindow
    { 
        Q_OBJECT
    
    public:
        VideoPlayer(QWidget *parent = nullptr);
        ~VideoPlayer();
        //重写事件过滤器函数
        virtual bool eventFilter(QObject *watched,QEvent *event);
        void add_Layout(QWidget *w);
    
    private slots:
        void on_listWidget_itemDoubleClicked(QListWidgetItem *item);
    
        void on_pushButton_start_clicked();
    
        void on_pushButton_stop_cont_clicked();
    
        void on_pushButton_stop_clicked();
    
        void on_pushButton_fullscreen_clicked();
    
        void on_pushButton_prev_clicked();
    
        void on_pushButton_next_clicked();
    
        void on_pushButton_add_video_clicked();
    
        void on_pushButton_del_video_clicked();
    
        void on_pushButton_clear_video_clicked();
    
        void on_horizontalSlider_sliderMoved(int position);
    
        void on_verticalSlider_sliderMoved(int position);
    
        //周期改变函数
        void set_sider(qint64 duration);
        //进度改变
        void set_value(qint64 position);
    
    private:
        Ui::VideoPlayer *ui;
        QMediaPlayer *player;
        //QVideoWidget *videow;
        MyVideoWidget *videow;
        QMediaPlaylist *playlist;
        QString video_duration;
    };
    #endif // VIDEOPLAYER_H

videoplayer.cpp

#include "videoplayer.h"
    #include "ui_videoplayer.h"
    #include <QFileDialog>
    #include <QTime>
    #include <QDebug>
    #include <QKeyEvent>
    
    VideoPlayer::VideoPlayer(QWidget *parent)
        : QMainWindow(parent)
        , ui(new Ui::VideoPlayer)
    { 
        ui->setupUi(this);
    
        player = new QMediaPlayer(this);
        videow = new MyVideoWidget(this);
        playlist = new QMediaPlaylist(this);
    
        //为videow安装过滤器 ----- 主窗口
        //videow->installEventFilter(this);
    
        //将QVideoWidget加入布局管理器
        ui->horizontalLayout->addWidget(videow);
        //设置QMediaPlayer的videooutput
        player->setVideoOutput(videow);
    
        //设置播放模式
        playlist->setPlaybackMode(QMediaPlaylist::Loop);
        //设置播放器的播放列表
        player->setPlaylist(playlist);
    
        //连接信号和槽
        QObject::connect(player,SIGNAL(durationChanged(qint64)),this,SLOT(set_sider(qint64)));
        QObject::connect(player,SIGNAL(positionChanged(qint64)),this,SLOT(set_value(qint64)));
    
        //禁止暂停按钮
        ui->pushButton_stop_cont->setEnabled(false);
    }
    
    VideoPlayer::~VideoPlayer()
    { 
        delete ui;
    }
    
    bool VideoPlayer::eventFilter(QObject *watched,QEvent *event)
    { 
        //按键事件
        if(event->type()==QEvent::KeyPress){ 
            QKeyEvent *keyevent = dynamic_cast<QKeyEvent *>(event);
            //按了Esc,退出全屏
            if(keyevent->key()==Qt::Key_Escape){ 
                //恢复播放窗口为子窗口
                videow->setWindowFlag(Qt::SubWindow);
                //退出全屏
                videow->showNormal();
    
                //重设父窗口
                videow->setParent(this);
                //重新加入布局管理器
                ui->horizontalLayout->addWidget(videow);
            }
        }
    
        //调用基类的过滤器处理函数
        return QMainWindow::eventFilter(watched,event);
    }
    
    void VideoPlayer::add_Layout(QWidget *w)
    { 
        ui->horizontalLayout->addWidget(w);
    }
    
    void VideoPlayer::on_listWidget_itemDoubleClicked(QListWidgetItem *item)
    { 
        int row = ui->listWidget->currentRow();
        playlist->setCurrentIndex(row);
    
        //设置音量
        player->setVolume(ui->verticalSlider->value());
        player->play();
    
        ui->pushButton_stop_cont->setEnabled(true);
    }
    
    //开始播放
    void VideoPlayer::on_pushButton_start_clicked()
    { 
        //当选中新的视频文件或者不是暂停状态===>重新播放
        if(ui->listWidget->currentRow()!=playlist->currentIndex()||
                player->state()!=QMediaPlayer::PausedState){ 
            //指定当前播放文件
            int row = ui->listWidget->currentRow();
            playlist->setCurrentIndex(row);
            //设置音量
            player->setVolume(ui->verticalSlider->value());
        }
    
        player->play();
    
        ui->pushButton_stop_cont->setEnabled(true);
    }
    
    //停止
    void VideoPlayer::on_pushButton_stop_cont_clicked()
    { 
        player->pause();
    
        ui->pushButton_stop_cont->setEnabled(false);
    }
    
    //暂停
    void VideoPlayer::on_pushButton_stop_clicked()
    { 
        player->stop();
    
        ui->pushButton_stop_cont->setEnabled(false);
    }
    
    //全屏
    void VideoPlayer::on_pushButton_fullscreen_clicked()
    { 
        //把子窗口提升为顶层窗口
        videow->setWindowFlag(Qt::Window);
        //全屏
        videow->showFullScreen();
    }
    
    void VideoPlayer::on_pushButton_prev_clicked()
    { 
        int row = ui->listWidget->currentRow();
        if(row==0)
            row = ui->listWidget->count();
        row--;
    
        ui->listWidget->setCurrentRow(row);
        on_listWidget_itemDoubleClicked(ui->listWidget->currentItem());
    }
    
    void VideoPlayer::on_pushButton_next_clicked()
    { 
        int row = ui->listWidget->currentRow();
        if(row==ui->listWidget->count()-1)
            row = 0;
        else
            row++;
    
        ui->listWidget->setCurrentRow(row);
        on_listWidget_itemDoubleClicked(ui->listWidget->currentItem());
    }
    
    void VideoPlayer::on_pushButton_add_video_clicked()
    { 
        QStringList video_files = QFileDialog::getOpenFileNames(this,"选择视频文件","./video","*.mp3 *.mp4 *.avi");
    
        //去重
        for(int i=0;i<ui->listWidget->count();i++){ 
            for(int j=0;j<video_files.count();j++){ 
                if(ui->listWidget->item(i)->text()==video_files.at(j)){ 
                    video_files.removeAt(j);
                    break;
                }
            }
        }
    
        //如果无添加文件，直接返回
        if(video_files.isEmpty())
            return;
    
        //添加到listWidget和playlist
    
        for(int i=0;i<video_files.count();i++){ 
            QString file = video_files.at(i);
            //把文件加入播放列表
            playlist->addMedia(QUrl::fromLocalFile(file));
        }
    
        ui->listWidget->addItems(video_files);
        //定位
        ui->listWidget->setCurrentRow(0);
    }
    
    void VideoPlayer::on_pushButton_del_video_clicked()
    { 
        int row = ui->listWidget->currentRow();
        //取出一项
        QListWidgetItem *item = ui->listWidget->takeItem(row);
    
        if(item){ 
            delete item;
        }
    
        //如果删除了正在播放的视频,禁止暂停
        if(row==playlist->currentIndex())
            ui->pushButton_stop_cont->setEnabled(false);
    
        //从播放列表删除
        playlist->removeMedia(row);
    }
    
    void VideoPlayer::on_pushButton_clear_video_clicked()
    { 
        ui->listWidget->clear();
        //清空播放列表
        playlist->clear();
    
        ui->pushButton_stop_cont->setEnabled(false);
    }
    
    void VideoPlayer::on_horizontalSlider_sliderMoved(int position)
    { 
        player->setPosition(position);
    }
    
    void VideoPlayer::on_verticalSlider_sliderMoved(int position)
    { 
        player->setVolume(position);
        //更新显示
        ui->label_volume->setText(QString("音量:%1").arg(position));
    }
    
    //周期改变函数
    void VideoPlayer::set_sider(qint64 duration)
    { 
        qDebug()<<duration;
    
        if(duration!=0)
        { 
            //设置进度条最大值
            ui->horizontalSlider->setRange(0,duration);
    
            QTime t = QTime(duration/1000/60/60,duration/1000/60%60,duration/1000%60);
            //显示周期
            video_duration = t.toString("hh:mm:ss");
            ui->label_duration_position->setText(QString("00:00:00/%1").arg(video_duration));
    
            //显示歌曲切换
            ui->listWidget->setCurrentRow(playlist->currentIndex());
        }
    }
    
    //进度改变
    void VideoPlayer::set_value(qint64 position)
    { 
        //更新进度条的值
        ui->horizontalSlider->setValue(position);
    
        QTime t = QTime(position/1000/60/60,position/1000/60%60,position/1000%60);
        //显示进度
        ui->label_duration_position->setText(QString("%1/%2").
            arg(t.toString("hh:mm:ss")).arg(video_duration));
    }

myvideowidget.h

#ifndef MYVIDEOWIDGET_H
    #define MYVIDEOWIDGET_H
    
    #include <QVideoWidget>
    
    class MyVideoWidget : public QVideoWidget
    { 
        Q_OBJECT
    public:
        MyVideoWidget(QWidget *parent=0);
        //重写按键事件处理函数
        virtual void keyPressEvent(QKeyEvent *event);
    
    private:
        QWidget *p;
    };
    
    #endif // MYVIDEOWIDGET_H

myvideowidget.cpp

#include "myvideowidget.h"
    #include <QKeyEvent>
    #include "videoplayer.h"
    
    MyVideoWidget::MyVideoWidget(QWidget *parent):QVideoWidget(parent)
    { 
        //记录父对象
        p = parent;
    }
    
    void MyVideoWidget::keyPressEvent(QKeyEvent *event)
    { 
        if(event->key()==Qt::Key_Escape){ 
            //恢复播放窗口为子窗口
            this->setWindowFlag(Qt::SubWindow);
            //退出全屏
            this->showNormal();
    
            //重设父窗口
            this->setParent(p);
            //重新加入布局管理器
            VideoPlayer *vp = dynamic_cast<VideoPlayer *>(p);
            vp->add_Layout(this);
        }
    
        return QVideoWidget::keyPressEvent(event);
    }

main.cpp

#include "videoplayer.h"
    
    #include <QApplication>
    
    int main(int argc, char *argv[])
    { 
        QApplication a(argc, argv);
        VideoPlayer w;
        w.show();
        return a.exec();
    }

[完整工程代码：https://download.csdn.net/download/weixin\_43793181/20334966][https_download.csdn.net_download_weixin_43793181_20334966]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80Mzc5MzE4MQ_size_16_color_FFFFFF_t_70]: /images/20221120/97214e112ca0436381ceae371e110512.png
[https_download.csdn.net_download_weixin_43793181_20334966]: https://download.csdn.net/download/weixin_43793181/20334966