Qt实现本地音乐播放器

 mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include 
#include 
#include 
namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();
private slots:
    void init();

    void on_btnAdd_clicked();

    void on_btnPlay_clicked();

    void on_btnPause_clicked();

    void on_btnStop_clicked();

    void on_btnPrevious_clicked();

    void on_btnNext_clicked();

    void on_btnSound_clicked();

    void on_sliderVolumn_valueChanged(int value);

    void on_listWidget_doubleClicked(const QModelIndex &index);

    void on_btnRemove_clicked();

    void on_btnClear_clicked();

    void on_sliderPosition_valueChanged(int value);

private:
    Ui::MainWindow *ui;

    QMediaPlayer *player;
    QMediaPlaylist *playlist;
    QString durationTime,positionTime;//总时间，当前位置的时间
private slots:
    void onStateChanged(QMediaPlayer::State state);//播放状态
    void onPlaylistChanged(int position);
    void onDurationChanged(qint64 duration);
    void onPositionChanged(qint64 position);
};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include 
#include 
#include 
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    init();

}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::init()
{
    player=new QMediaPlayer(this);
    playlist=new QMediaPlaylist(this);
    playlist->setPlaybackMode(QMediaPlaylist::Loop);//循环播放
    player->setPlaylist(playlist);
    connect(player,SIGNAL(stateChanged(QMediaPlayer::State)),
            this,SLOT(onStateChanged(QMediaPlayer::State)));
    //状态改变
    connect(player,SIGNAL(durationChanged(qint64)),
            this,SLOT(onDurationChanged(qint64)));
    //歌曲时长
    connect(player,SIGNAL(positionChanged(qint64)),
            this,SLOT(onPositionChanged(qint64)));
    //位置
    connect(playlist,SIGNAL(currentIndexChanged(int)),
            this,SLOT(onPlaylistChanged(int)));
    //当前索引改变

    ui->listWidget->setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
}

void MainWindow::on_btnAdd_clicked()
{
    QString curpath=QDir::homePath();
    //qDebug()<addMedia(QUrl::fromLocalFile(aFile));
        //qDebug()<listWidget->addItem(fileInfo.fileName());
        //qDebug()<state()!=QMediaPlayer::PlayingState)
        playlist->setCurrentIndex(0);
    player->play();
}

void MainWindow::on_btnPlay_clicked()
{
    if(playlist->currentIndex()<0)
        playlist->setCurrentIndex(0);
    player->play();
}

void MainWindow::on_btnPause_clicked()
{
    player->pause();
}

void MainWindow::on_btnStop_clicked()
{
    player->stop();
}

void MainWindow::on_btnPrevious_clicked()
{
    playlist->previous();
    player->play();
}

void MainWindow::on_btnNext_clicked()
{
    playlist->next();
    player->play();
}

void MainWindow::on_btnSound_clicked()
{
    bool mute=player->isMuted();
    player->setMuted(!mute);
    if(mute){
        ui->btnSound->setIcon(QIcon(":/images/images/volumn.bmp"));
    }
    else{
        ui->btnSound->setIcon(QIcon(":/images/images/mute.bmp"));
    }
}

void MainWindow::on_sliderVolumn_valueChanged(int value)
{
    player->setVolume(value);
}

void MainWindow::on_listWidget_doubleClicked(const QModelIndex &index)
{
    int rowNo=index.row();
    //qDebug()<setCurrentIndex(rowNo);
    player->play();
}

void MainWindow::on_btnRemove_clicked()
{
    int pos=ui->listWidget->currentRow();
    QListWidgetItem *item=ui->listWidget->takeItem(pos);
    delete item;
    playlist->removeMedia(pos);
}

void MainWindow::on_btnClear_clicked()
{
    playlist->clear();
    ui->listWidget->clear();
    player->stop();
}

void MainWindow::on_sliderPosition_valueChanged(int value)
{
    player->setPosition(value);//?
}

void MainWindow::onStateChanged(QMediaPlayer::State state)
{
    ui->btnStop->setEnabled(state==QMediaPlayer::PlayingState);
    ui->btnPause->setEnabled(state==QMediaPlayer::PlayingState);
    ui->btnPlay->setEnabled(!(state==QMediaPlayer::PlayingState));
}

void MainWindow::onPlaylistChanged(int position)
{
    //qDebug()<listWidget->setCurrentRow(position);
    QListWidgetItem *item=ui->listWidget->currentItem();
    if(item)
        ui->LabCurMedia->setText(item->text());
}

void MainWindow::onDurationChanged(qint64 duration)
{
    ui->sliderPosition->setMaximum(duration);
    int secs=duration/1000;
    //qDebug()<LabRatio->setText(positionTime+"/"+durationTime);
}

void MainWindow::onPositionChanged(qint64 position)
{
    if(ui->sliderPosition->isSliderDown())return ;
    ui->sliderPosition->setSliderPosition(position);
    int secs=position/1000;
    int mins=secs/60;
    secs=secs%60;
    positionTime=QString::asprintf("%d:%02d",mins,secs);
    ui->LabRatio->setText(positionTime+"/"+durationTime);
}

qss:

QLabel{
font: 12pt "楷体";
}
QFrame#line_2{
color:rgb(68, 170, 232);
}
#groupBox{
font: 12pt "楷体";
}
QListView {
    outline: none;
}
#listWidget{/*
border-style:solid;
border-color:rgb(69, 173, 237);
border-width:2px;*/
border:none;
}
#listWidget::item {
    background-color: #ffffff;
    color: #000000;
    border: transparent;
    border-bottom: 1px solid #dbdbdb;
    padding: 8px;
}

#listWidget::item:hover {
    background-color: #f5f5f5;
}

#listWidget::item:selected {
    border-left: 5px solid rgb(69, 173, 237);
}


#centralWidget{
background-color: rgb(255, 255, 255);
}

QSlider{
border:none;
}
QSlider::groove:horizontal {
border: 1px solid #bbb;
background: white;
height: 8px;
border-radius: 4px;
}
QSlider::sub-page:horizontal {
background: rgb(69, 173, 237);

border: 1px solid #777;
height: 8px;
border-radius: 4px;
}
QSlider::add-page:horizontal {
background: #fff;
border: 1px solid #777;
height: 8px;
border-radius: 4px;
}
QSlider::handle:horizontal {
  background: qradialgradient(spread:pad, cx:0.5, cy:0.5, radius:0.5, fx:0.5, fy:0.5, 
    stop:0.6 #45ADED, stop:0.778409 rgba(255, 255, 255, 255));
border: 1px solid #777;
border-radius:10px;
width: 20px;
margin-top: -6px;
margin-bottom: -6px;

}
QSlider::handle:horizontal:hover {
    background: qradialgradient(spread:pad, cx:0.5, cy:0.5, radius:0.5, fx:0.5, fy:0.5, stop:0.6 #2A8BDA, 
    stop:0.778409 rgba(255, 255, 255, 255));
border: 1px solid #444;
border-radius:10px;
width: 20px;
margin-top: -6px;
margin-bottom: -6px;
}

QPushButton:hover{
border:2px solid rgb(69, 173, 237);
}
QPushButton{
font: 14pt "方正小标宋简体";
color:rgb(108,108,108);
min-width:150px;
max-width:150px;
min-height:50px;
max-height:50px;
border:2px solid rgb(214,214,214);
border-radius:20px;
}
QScrollBar:vertical{

margin:16px 0px 16px 0px;

background-color:rgb(255,255,255);

border:0px;

width:14px;

}

QScrollBar::handle:vertical{

background-color:rgb(69, 173, 237);

border-radius:7px;

width:13px;

}

QScrollBar::handle:vertical:hover{

background-color:rgb(42, 139, 218);

}

QScrollBar::sub-line:vertical{

subcontrol-position:top;

subcontrol-origin:margin;

background-color:rgb(255,255,255);


height:0px;

}

QScrollBar::add-line:vertical{

subcontrol-position:bottom;

subcontrol-origin:margin;

background-color:rgb(255,255,255);


height:0px;

}


QScrollBar::sub-page:vertical,QScrollBar::add-page:vertical{

background-color:rgb(255,255,255);

}

源码：Qt与学习通页面: 记录与Qt相关的代码 - Gitee.com