Qt4下的madplay播放器（转载）

经过几天的努力，利用Qt4实现的前台界面，madplay实现的后台播放器总算是能正常运行了(在fs2410开发板上的运行界面如下)，下面的笔记简要说明了实现方式。

 

           

1．  main.cpp 文件

 

#include

#include"audio_player.h"

#include

#include

 

int main(int argc, char *argv[])

{

        QApplication app(argc, argv);

 

        QTextCodec::setCodecForLocale(QTextCodec::codecForLocale());

        QTextCodec::setCodecForTr(QTextCodec::codecForName("GBK"));

        QTextCodec::setCodecForCStrings(QTextCodec::codecForName("GBK"));

      

        audio_player myAudio;

 

        myAudio.setFont(QFont("wenquanyi",12,QFont::Normal));   //设置字体

        myAudio.show();

        return app.exec();

}

 

2．Audio_player.h 文件

 

#ifndef _AUDIO_PLAYER_H_

#define _AUDIO_PLAYER_H_

 

#include

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#include

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#include

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struct Tag_Header{

        char Header[3];

        char ver;       

        char Revision;

        char Flag;

        char Size[4];

};

 

struct Tag_Trailer{

        char Header[3];

        char Title[30];

        char Artist[30];

        char Album[30];

        char Year[4];

        char Comment[28];

        char Cenre[1];

};

 

class audio_player : public QDialog

{

        Q_OBJECT

public:

        audio_player(QWidget *parent = 0, Qt::WindowFlags f = 0);

        void readInfo(QString file);

        void Tag_GetTrailer(void);

        void Tag_GetHeader(void);

private slots:

        void slotStart();

        void slotUp();

        void slotDown();

        void slotOpen();   

        void slotGetVol();

        void slotShowTime();

private:

        QToolButton *start;

        QToolButton *up;

        QToolButton *down;

        QSlider *slider;

        QHBoxLayout *keyLayout;

        QGridLayout *mainLayout;

 

        QLabel *mp3Title;

        QLabel *mp3Art;

        QLabel *mp3Album;

        QLabel *mp3Time;

        QLabel *mp3Length;

   

        QTimer *timer;

   

        QString fileName;

        QString filePath;

        QStringList musicList;

        QString command;

        QString backend;

        QString Mp3Title_copy;

 

        Tag_Header Mp3Header;

        Tag_Trailer Mp3Trailer;

 

        int nCount;

        int index;  

        FILE *fp;

};

 

#endif

 

3．  Audio_player.cpp 文件

 

    #include"audio_player.h"

 

static int fd;

int tm =0;            //分钟

int ts =0;            //秒

 

audio_player::audio_player(QWidget *parent, Qt::WindowFlags f)

        : QDialog(parent, f)   

{   

        QPalette p = this->palette();

        p.setColor(QPalette::Window,Qt::black);   //设置背景色

        this->setPalette(p);

   

        timer = new QTimer(this);

      

        mainLayout = new QGridLayout(this);

        keyLayout = new QHBoxLayout(); 

 

        mp3Title = new QLabel;

        mp3Art = new QLabel;

        mp3Album = new QLabel;

        mp3Time = new QLabel;

        mp3Length = new QLabel;

        mp3Length->setText("04:23");

       

        p.setColor(QPalette::WindowText,Qt::white);   //设置前景色   

        mp3Title->setPalette(p);

        mp3Art->setPalette(p);

        mp3Album->setPalette(p);

        mp3Time->setPalette(p);

        mp3Length->setPalette(p);

       

        start = new QToolButton;                      //开始

        start->setText(tr("start"));

        start->setIcon(QPixmap(":/images/3.png"));

        start->setIconSize(QPixmap(":/images/3.png").size());

        start->setAutoRaise(TRUE);

        start->setToolButtonStyle(Qt::ToolButtonIconOnly);

 

        up = new QToolButton;                         //上一曲

        up->setText(tr("up"));

        up->setIcon(QPixmap(":/images/1.png"));

        up->setIconSize(QPixmap(":/images/1.png").size());

        up->setAutoRaise(TRUE);

        up->setToolButtonStyle(Qt::ToolButtonIconOnly);

 

        down = new QToolButton;                             //下一曲

        down->setText(tr("down"));

        down->setIcon(QPixmap(":/images/5.png"));

        down->setIconSize(QPixmap(":/images/5.png").size());

        down->setAutoRaise(TRUE);

        down->setToolButtonStyle(Qt::ToolButtonIconOnly);

 

        slider = new QSlider(Qt::Horizontal);                //音量

        slider->setMinimum(40);

        slider->setMaximum(120);

        slider->setValue(80);

        slider->setTickPosition(QSlider::TicksBelow);

  

        p.setColor(QPalette::Window,Qt::blue);

        slider->setPalette(p);          

 

        keyLayout->addWidget(mp3Time);

        keyLayout->addWidget(up);

        keyLayout->addWidget(start);

        keyLayout->addWidget(down);

        keyLayout->addWidget(mp3Length);

                  

        mainLayout->addWidget(mp3Title,0,0,Qt::AlignHCenter);

        mainLayout->addWidget(mp3Art,1,0,Qt::AlignHCenter);

        mainLayout->addWidget(mp3Album,2,0,Qt::AlignHCenter);

        mainLayout->addWidget(slider,3,0);

        mainLayout->addLayout(keyLayout,4,0);

 

        connect(start,SIGNAL(clicked()),this,SLOT(slotOpen()));

        connect(up,SIGNAL(clicked()),this,SLOT(slotUp()));

        connect(down,SIGNAL(clicked()),this,SLOT(slotDown()));

        connect(slider,SIGNAL(valueChanged(int)),SLOT(slotGetVol()));

        connect(timer,SIGNAL(timeout()),this,SLOT(slotShowTime()));

       

        fd =::open("/dev/mixer", O_RDWR);        //打开mixer设备，用于音量调节

        if (fd ==  - 1)

        {

            perror("unable to open /dev/mixer");

            exit(1);

        }

   

        QDir dir("/mnt/udisk/mp3");             

        filePath = tr("/mnt/udisk/mp3/");                    //设置播放目录

 

musicList = dir.entryList(QDir::Files,QDir::Name);   //遍历播放目录下的所有歌曲

 

        nCount = musicList.size();                           //获得歌曲数目

        fileName =  static_cast(musicList.at(0));   //提取歌曲名称

 

        command=tr("./sbin/madplay ");             

        backend = tr(" &");                                 //后台播放

   

        setWindowTitle(tr("Madplayer"));                    //设置窗口名称

        slotStart();                                        //开始播放

        this->sizeHint();   

}

 

void audio_player::slotOpen()

{

        QFileDialog fileDilog(this);                      //建立文件对话框

        QStringList openList;

 

        fileDilog.setFileMode(QFileDialog::AnyFile);

        fileDilog.setDirectory (trUtf8("/mnt/udisk/mp3"));

        fileDilog.setNameFilter(trUtf8("*.mp3"));       //仅显示 .mp3 文件         

        fileDilog.setViewMode(QFileDialog::List);       //以list方式显示

        fileDilog.resize(320,240);                      //对话框尺寸 

        if (fileDilog.exec())   

            openList =fileDilog.selectedFiles();

 

        fileName = static_cast(openList.at(0));   //获取歌曲路径和名称

        fileName.remove(0,15);                //移除15个字符的路径，得到歌曲名

 

        system("killall -9 madplay");         //关闭madplay 进程

        slotStart();

}

 

int flag =1;

 

void audio_player::slotShowTime()

{

        char disp_buf[5];

        FILE *out;

        char str[30];

 

        ts++;

        if(ts >= 60) {

            tm++;

            ts = 0;

        }

        if(tm >= 60) {

            tm = 0;

            ts = 0;

        }

 

        sprintf(disp_buf,"%02d:%02d",tm,ts);

        QString text = disp_buf;

        mp3Time->setText(text);                        //显示时间

 

        /* 查看当前进程列表中是否有 madplay 进程存在，如果不存在，说明当前歌曲播放完毕，则启动播放下一曲

        */

        system("ps |pgrep -l madplay >/usr/run.dat"); 

        out = fopen ("/usr/run.dat", "r"); 

 

        fread (str, sizeof (str), 1, out);

        printf("%s\n\r",str);

 

        if(str[0]<48 ) slotDown();

   

        fclose (out);

}

 

void audio_player::slotGetVol()

{

        int usr_volume;

        usr_volume = slider->value();                //设置音量大小

        ioctl(fd,MIXER_WRITE(0),&usr_volume);        //调节音量        

}

 

void audio_player::slotStart()

{

       char *S;

        readInfo(fileName);

  

        tm =0;

        ts =0;

 

        if(flag!=1)

           {system("killall -9 madplay");flag = 1;}

        else

        {  

flag=0;      

            QString command_full = command;

 

            command_full.append(filePath);

            command_full.append(fileName);

            command_full.append(backend);

 

            S = (command_full.toAscii()).data();

            printf("%s\n\r",S);   

            timer->start(1000);        //设置定是器的时间为一秒

            system(S);  

        }

}

 

void audio_player::slotUp()

{     

        QString command_full = command;

        system("killall -9 madplay");         //停止播放当前歌曲

       

        index = musicList.indexOf(fileName);  //获取当前歌曲索引 

   

        index--;                              //获取上一曲索引

        if(index < 0)

            index = nCount-1;

 

        /* 根据上一曲索引找到上一曲文件名 */

        fileName = static_cast(musicList.at(index));

 

        flag = 1;      

        slotStart();        //播放

}

 

void audio_player::slotDown()

{

        QString command_full = command;

        system("killall -9 madplay");

   

        index = musicList.indexOf(fileName);

       

        index++;

        if(index >(nCount-1))

            index = 0;

        fileName = static_cast(musicList.at(index));

        flag = 1;

        slotStart();

}

 

void audio_player::Tag_GetTrailer(void)

{

        fseek(fp,-128L,SEEK_END);

        fread(Mp3Trailer.Header,3,1,fp);

 

        fseek(fp,-125L,SEEK_END);

        fread(Mp3Trailer.Title,30,1,fp);

 

        fseek(fp,-95L,SEEK_END);

        fread(Mp3Trailer.Artist,30,1,fp);

           

        fseek(fp,-65L,SEEK_END);

        fread(Mp3Trailer.Album,30,1,fp);

               

        fseek(fp,-35L,SEEK_END);

        fread(Mp3Trailer.Year,4,1,fp);

                  

        fseek(fp,-31L,SEEK_END);

        fread(Mp3Trailer.Comment,28,1,fp);

                          

        fseek(fp,-1L,SEEK_END);

        fread(Mp3Trailer.Cenre,1,1,fp);

}

 

    /* 读取mp3文件ID3标签 */

void audio_player::Tag_GetHeader(void)

{

        fseek(fp,0,SEEK_SET);

        fread(Mp3Header.Header,sizeof(Mp3Header.Header),1,fp);

                             

        fseek(fp,3,SEEK_CUR);

        fread(&Mp3Header.ver,sizeof(Mp3Header.ver),1,fp);

                                   

        fseek(fp,4,SEEK_CUR);

        fread(&Mp3Header.Revision,sizeof(Mp3Header.Revision),1,fp);

                       

        fseek(fp,5,SEEK_CUR);

        fread(&Mp3Header.Flag,sizeof(Mp3Header.Flag),1,fp);

                                     

        fseek(fp,6,SEEK_CUR);

        fread(Mp3Header.Size,sizeof(Mp3Header.Size),1,fp);

}

 

    /* 获取mp3文件信息 */

void audio_player::readInfo(QString file)

{  

        QString local_ch;

        char *S;

  

        QString file_full = filePath;

        file_full.append(file);

 

        S = (file_full.toAscii()).data();

 

        /* 以二进制格式打开当前文件进行分析 */

        if((fp=fopen(S,"rb"))==NULL)

        {

            printf("ERROR:can't open the file!");

            getchar();

            exit(1);

        }

 

        Tag_GetTrailer();

        Tag_GetHeader();

   

        QString sbuf;

 

        sbuf = (tr(Mp3Trailer.Title)).section("   " ,0,0);   

        mp3Title->setText(tr("%1").arg(sbuf,0));           //mp3文件标题

 

        sbuf = (tr(Mp3Trailer.Artist)).section("   ",0,1);

        mp3Art->setText(tr("%1").arg(sbuf,0));             //mp3 Artist

 

        sbuf = (tr(Mp3Trailer.Album)).section("  ",0,1);

        mp3Album->setText(tr("%1").arg(sbuf,0));           //mp3 Album

 

        fclose(fp);

}

 

链接：http://blog.chinaunix.net/u3/108905/showart_2319016.html