基于QtAV的简易播放器（开源）

这个开源代码，是我利用QtAV源码，提取其中一部分代码，进行整合到我自己项目中，做的一个小型播放器测试，至于怎么安装一些环境以及QtAV源码编译在我以前写的一篇博客中可以看到（Qt第三方库QtAV--- ubuntu编译与运行），因为看到有人提出说怎么调用接口，怎么整合到自己项目中的问题， 因为网上资料关于QtAV的的确很少，由于也是去年年前带我的师傅让我了解调用接口，顺便做个简单的播放器，所以和大家分享下！！！该播放器主要实现了快进、后退、暂停、播放、选择文件、调节音量大小等。

整个环境即编译条件在ubuntu   64位      Qt  5.7.0下运行成功！！！

这是运行界面截图

废话不多说，直接上代码！！！

QtAVPlayer.pro

#-------------------------------------------------
#
# Project created by QtCreator 2017-01-16T22:05:51
# author: yangshujie
#-------------------------------------------------

QT       += core gui
QT += avwidgets
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = QtAVPlayer
TEMPLATE = app

SOURCES += main.cpp\
        mainwindow.cpp \
    Slider.cpp

HEADERS  += mainwindow.h \
    Slider.h

main.cpp

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    Widgets::registerRenderers();
    QApplication a(argc, argv);
    MainWindow play;
    play.show();
    //play.setGeometry();
    play.resize(800,500);
    return a.exec();
}

Slider.h

#ifndef SLIDER_H
#define SLIDER_H

#include <QSlider>

class Slider : public QSlider
{
    Q_OBJECT
public:
    Slider(QWidget *parent = 0);
    ~Slider();

signals:
    void onEnter();
    void onLeave();
    void onHover(int pos, int value);

protected:
    virtual void enterEvent(QEvent* event);
    virtual void leaveEvent(QEvent *e);
    virtual void mouseMoveEvent(QMouseEvent* event);
    virtual void mousePressEvent(QMouseEvent *event);
//#if CODE_FOR_CLICK == 1
    inline int pick(const QPoint &pt) const;
    int pixelPosToRangeValue(int pos) const;
    void initStyleOption_Qt430(QStyleOptionSlider *option) const;
//#endif
};

#endif // SLIDER_H

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include "Slider.h"
#include <QMainWindow>
#include <QWidget>
#include <QString>
#include <QtAV>
#include <QLabel>
#include <QTime>
#include <QAction>
#include <QToolTip>
#include <QWidgetAction>
#include <QFileDialog>
#include <QVBoxLayout>
#include <QToolButton>
#include <QSpinBox>
#include <QMessageBox>
#include <QTimeEdit>
#include <QtAVWidgets>
#include <QtAV/AVClock.h>
#include <QtAV/AVPlayer.h>

using namespace QtAV;
//class Slider;
class MainWindow : public QWidget
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();
public slots:
    void play(const QString &name);
    void openFile();
    void togglePlayPause();
private slots:
    void setupUi();
    void initPlayer();
    void setVolume();
    void setRepeateMax(int m);

    void stopUnload();
    void seek();
    void onPaused(bool p);
    void onStartPlay();
    void onStopPlay();

    void onSeekFinished();
    void onTimeSliderHover(int pos, int value);
    void onTimeSliderLeave();
    void handleError(const QtAV::AVError& e);
    void onPositionChange(qint64 pos);
    void showHideVolumeBar();
    void tryShowControlBar();
    void toggleRepeat(bool r);
    void repeatAChanged(const QTime& t);
    void repeatBChanged(const QTime& t);

private:
    int mRepeateMax;
    int mCursorTimer;
    bool mIsReady,mHasPendingPlay;
    VideoOutput *mpVo;
    AVPlayer *mpPlayer;
    AVClock *mpClock;
    VideoRenderer *mpRenderer, *mpTempRenderer;

    QString mFile;
    QString mTitle;
    QTimeEdit *mpRepeatA, *mpRepeatB;
    QVBoxLayout *mpPlayerLayout,*mainLayout;
    QAction *mpRepeatEnableAction;
    QWidgetAction *mpRepeatAction;
    QWidget *mpControl;
    QLabel *mpCurrent, *mpEnd;
    QLabel *mpTitle;
    QLabel *mpSpeed;
    Slider *mpTimeSlider, *mpVolumeSlider;
    QSpinBox *mpRepeatBox;
    QToolButton *mpVolumeBtn;
    QToolButton *mpPlayPauseBtn;
    QToolButton *mpStopBtn, *mpForwardBtn, *mpBackwardBtn;
    QToolButton *mpOpenBtn;
    VideoPreviewWidget *m_preview;
};

#endif // MAINWINDOW_H

Slider.cpp

#include "Slider.h"

/*  smplayer, GUI front-end for mplayer.
    Copyright (C) 2006-2010 Ricardo Villalba <rvm@escomposlinux.org>

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) version 3, or any
    later version accepted by the membership of KDE e.V. (or its
    successor approved by the membership of KDE e.V.), Trolltech ASA
    (or its successors, if any) and the KDE Free Qt Foundation, which shall
    act as a proxy defined in Section 6 of version 3 of the license.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library.  If not, see <http://www.gnu.org/licenses/>.
*/

#define CODE_FOR_CLICK 1 // 0 = old code, 1 = code copied from QSlider, 2 = button swap

#include "Slider.h"
#include <QApplication>
#include <QMouseEvent>

#if CODE_FOR_CLICK <= 1
#include <QStyle>
#if CODE_FOR_CLICK == 1
#include <QStyleOption>
#endif
#endif

#if QT_VERSION < 0x040300
#define initStyleOption initStyleOption_Qt430
#endif //QT_VERSION

Slider::Slider(QWidget *parent):
    QSlider(parent)
{
    setOrientation(Qt::Horizontal);
    setMouseTracking(true); //mouseMoveEvent without press.
}

Slider::~Slider()
{
}

#if CODE_FOR_CLICK == 1
// Function copied from qslider.cpp
inline int Slider::pick(const QPoint &pt) const
{
    return orientation() == Qt::Horizontal ? pt.x() : pt.y();
}

// Function copied from qslider.cpp and modified to make it compile
void Slider::initStyleOption_Qt430(QStyleOptionSlider *option) const
{
    if (!option)
        return;

    option->initFrom(this);
    option->subControls = QStyle::SC_None;
    option->activeSubControls = QStyle::SC_None;
    option->orientation = orientation();
    option->maximum = maximum();
    option->minimum = minimum();
    option->tickPosition = (QSlider::TickPosition) tickPosition();
    option->tickInterval = tickInterval();
    option->upsideDown = (orientation() == Qt::Horizontal) ?
                     (invertedAppearance() != (option->direction == Qt::RightToLeft))
                     : (!invertedAppearance());
    option->direction = Qt::LeftToRight; // we use the upsideDown option instead
    option->sliderPosition = sliderPosition();
    option->sliderValue = value();
    option->singleStep = singleStep();
    option->pageStep = pageStep();
    if (orientation() == Qt::Horizontal)
        option->state |= QStyle::State_Horizontal;
}

// Function copied from qslider.cpp and modified to make it compile
int Slider::pixelPosToRangeValue(int pos) const
{
    QStyleOptionSlider opt;
    initStyleOption(&opt);
    QRect gr = style()->subControlRect(QStyle::CC_Slider, &opt, QStyle::SC_SliderGroove, this);
    QRect sr = style()->subControlRect(QStyle::CC_Slider, &opt, QStyle::SC_SliderHandle, this);
    int sliderMin, sliderMax, sliderLength;
    if (orientation() == Qt::Horizontal) {
        sliderLength = sr.width();
        sliderMin = gr.x();
        sliderMax = gr.right() - sliderLength + 1;
    } else {
        sliderLength = sr.height();
        sliderMin = gr.y();
        sliderMax = gr.bottom() - sliderLength + 1;
    }
    return QStyle::sliderValueFromPosition(minimum(), maximum(), pos - sliderMin,
                                           sliderMax - sliderMin, opt.upsideDown);
}

void Slider::enterEvent(QEvent *event)
{
    emit onEnter();
    QSlider::enterEvent(event);
}

void Slider::leaveEvent(QEvent *e)
{
    emit onLeave();
    QSlider::leaveEvent(e);
}

void Slider::mouseMoveEvent(QMouseEvent *e)
{
    const int o = style()->pixelMetric(QStyle::PM_SliderLength ) - 1;
    int v = QStyle::sliderValueFromPosition(minimum(), maximum(), e->pos().x()-o/2, width()-o, false);
    emit onHover(e->x(), v);
    QSlider::mouseMoveEvent(e);
}

// Based on code from qslider.cpp
void Slider::mousePressEvent(QMouseEvent *e)
{
    qDebug("pressed (%d, %d)", e->pos().x(), e->pos().y());
    if (e->button() == Qt::LeftButton) {
        QStyleOptionSlider opt;
        initStyleOption(&opt);
        const QRect sliderRect = style()->subControlRect(QStyle::CC_Slider, &opt, QStyle::SC_SliderHandle, this);
        const QPoint center = sliderRect.center() - sliderRect.topLeft();
        // to take half of the slider off for the setSliderPosition call we use the center - topLeft

        if (!sliderRect.contains(e->pos())) {
            qDebug("accept");
            e->accept();

            int v = pixelPosToRangeValue(pick(e->pos() - center));
            setSliderPosition(v);
            triggerAction(SliderMove);
            setRepeatAction(SliderNoAction);
            emit sliderMoved(v);//TODO: ok?
            emit sliderPressed(); //TODO: ok?
        } else {
            QSlider::mousePressEvent(e);
        }
    } else {
        QSlider::mousePressEvent(e);
    }
}
#endif // CODE_FOR_CLICK == 1
#if CODE_FOR_CLICK == 2
void Slider::mousePressEvent(QMouseEvent *e)
{
    // Swaps middle button click with left click
    if (e->button() == Qt::LeftButton) {
        QMouseEvent ev2(QEvent::MouseButtonRelease, e->pos(), e->globalPos(), Qt::MidButton, Qt::MidButton, e->modifiers());
        QSlider::mousePressEvent(&ev2);
    } else if (e->button() == Qt::MidButton) {
        QMouseEvent ev2(QEvent::MouseButtonRelease, e->pos(), e->globalPos(), Qt::LeftButton, Qt::LeftButton, e->modifiers());
        QSlider::mousePressEvent(&ev2);
    }
    else {
        QSlider::mousePressEvent(e);
    }
}
#endif // CODE_FOR_CLICK == 2
#if CODE_FOR_CLICK == 0
void Slider::mousePressEvent(QMouseEvent *e)
{
    // FIXME:
    // The code doesn't work well with right to left layout,
    // so it's disabled.
    if (qApp->isRightToLeft()) {
        QSlider::mousePressEvent(e);
        return;
    }

    int range = maximum()-minimum();
    int pos = (e->x() * range) / width();
    //qDebug( "width: %d x: %d", width(), e->x());
    //qDebug( "range: %d pos: %d value: %d", range, pos, value());

    // Calculate how many positions takes the slider handle
    int metric = qApp->style()->pixelMetric(QStyle::PM_SliderLength);
    double one_tick_pixels = (double)width() / range;
    int slider_handle_positions = (int)(metric / one_tick_pixels);

    /*
    qDebug("metric: %d", metric );
    qDebug("one_tick_pixels :%f", one_tick_pixels);
    qDebug("width() :%d", width());
    qDebug("slider_handle_positions: %d", slider_handle_positions);
    */

    if (abs(pos - value()) > slider_handle_positions) {
        setValue(pos);
        emit sliderMoved(pos);
    } else {
        QSlider::mousePressEvent(e);
    }
}
#endif

mainwindow.cpp

#include "mainwindow.h"
#include <QTimer>
const qreal kVolumeInterval = 0.04;

MainWindow::MainWindow(QWidget *parent) :
    QWidget(parent),mpPlayer(0),mpVo(0),mpTempRenderer(0)
{
    setWindowTitle("QtAV Player");
    setupUi();
}

MainWindow::~MainWindow()
{
    if (m_preview) {
        m_preview->close();
        delete m_preview;
    }
    if (mpVolumeSlider && !mpVolumeSlider->parentWidget()) {
        mpVolumeSlider->close();
        delete mpVolumeSlider;
        mpVolumeSlider = 0;
    }
}

void MainWindow::setupUi()
{
    mpPlayer = new AVPlayer(this);
    mainLayout = new QVBoxLayout();
    mainLayout->setSpacing(0);
    mainLayout->setMargin(0);
    setLayout(mainLayout);

    mpControl = new QWidget(this);
    mpControl->setMaximumHeight(30);

    mpTimeSlider = new Slider(mpControl);
    mpTimeSlider->setDisabled(true);
    mpTimeSlider->setTracking(true);
    mpTimeSlider->setOrientation(Qt::Horizontal);
    mpTimeSlider->setMinimum(0);

    mpCurrent = new QLabel(mpControl);
    mpCurrent->setToolTip(tr("Current time"));
    mpCurrent->setMargin(2);
    mpCurrent->setText(QString::fromLatin1("00:00:00"));

    mpEnd = new QLabel(mpControl);
    mpEnd->setToolTip(tr("Duration"));
    mpEnd->setMargin(2);
    mpEnd->setText(QString::fromLatin1("00:00:00"));

    mpTitle = new QLabel(mpControl);
    mpTitle->setToolTip(tr("Author"));
    mpTitle->setText(QString::fromLatin1("YangShuJie"));
    mpTitle->setIndent(8);

    mpPlayPauseBtn = new QToolButton(mpControl);
    mpPlayPauseBtn->setToolTip(tr("Play"));
    mpPlayPauseBtn->setIcon(QIcon(QString::fromLatin1("./image/play.png")));
    mpStopBtn = new QToolButton(mpControl);
    mpStopBtn->setToolTip(tr("Stop"));
    mpStopBtn->setIcon(QIcon(QString::fromLatin1("./image/stop.png")));
    mpBackwardBtn = new QToolButton(mpControl);
    mpBackwardBtn->setToolTip(tr("Backward"));
    mpBackwardBtn->setIcon(QIcon(QString::fromLatin1("./image/backward.png")));
    mpForwardBtn = new QToolButton(mpControl);
    mpForwardBtn->setToolTip(tr("Forward"));
    mpForwardBtn->setIcon(QIcon(QString::fromLatin1("./image/forward.png")));
    mpOpenBtn = new QToolButton(mpControl);
    mpOpenBtn->setToolTip(tr("Open"));
    mpOpenBtn->setIcon(QIcon(QString::fromLatin1("./image/open.png")));
    mpVolumeBtn = new QToolButton();
    mpVolumeBtn->setToolTip(tr("Volume"));
    mpVolumeBtn->setIcon(QIcon(QString::fromLatin1("./image/sound.png")));

    mpVolumeSlider = new Slider();
    mpVolumeSlider->hide();
    mpVolumeSlider->setOrientation(Qt::Horizontal);
    mpVolumeSlider->setMinimum(0);
    const int kVolumeSliderMax = 100;
    mpVolumeSlider->setMaximum(kVolumeSliderMax);
    //mpVolumeSlider->setMaximumHeight(12);
    mpVolumeSlider->setMaximumWidth(88);
    mpVolumeSlider->setValue(int(1.0/kVolumeInterval*qreal(kVolumeSliderMax)/100.0));
    setVolume();

    QWidgetAction *pWA = 0;
//  QLabel *pRepeatLabel = new QLabel(tr("Times"));
    QHBoxLayout *hb = new QHBoxLayout;
//    hb->addWidget(pRepeatLabel);
    hb->addWidget(mpRepeatBox);

    QVBoxLayout *vb = new QVBoxLayout;
    vb->addLayout(hb);
//    pRepeatLabel = new QLabel(tr("From"));
    mpRepeatA = new QTimeEdit();
    mpRepeatA->setDisplayFormat(QString::fromLatin1("HH:mm:ss"));
    mpRepeatA->setToolTip(tr("negative value means from the end"));
    connect(mpRepeatA, SIGNAL(timeChanged(QTime)), SLOT(repeatAChanged(QTime)));

    hb = new QHBoxLayout;
//    hb->addWidget(pRepeatLabel);
    hb->addWidget(mpRepeatA);
    vb->addLayout(hb);
//    pRepeatLabel = new QLabel(tr("To"));
    mpRepeatB = new QTimeEdit();
    mpRepeatB->setDisplayFormat(QString::fromLatin1("HH:mm:ss"));
    mpRepeatB->setToolTip(tr("negative value means from the end"));
    connect(mpRepeatB, SIGNAL(timeChanged(QTime)), SLOT(repeatBChanged(QTime)));
    hb = new QHBoxLayout;
//    hb->addWidget(pRepeatLabel);
    hb->addWidget(mpRepeatB);
    vb->addLayout(hb);
    QWidget *wgt = new QWidget;
    wgt->setLayout(vb);

    pWA = new QWidgetAction(0);
    pWA->setDefaultWidget(wgt);
    pWA->defaultWidget()->setEnabled(false);
     mpRepeatAction = pWA;

    mpVo = new VideoOutput(this);
    if (!mpVo->widget()) {
        QMessageBox::warning(0, QString::fromLatin1("QtAV error"), tr("Can not create video renderer"));
        return;
    }
    mpPlayer->setRenderer(mpVo);
    mainLayout->addWidget(mpVo->widget());
    mainLayout->addWidget(mpTimeSlider);
    mainLayout->addWidget(mpControl);

    QHBoxLayout *controlLayout = new QHBoxLayout();
    controlLayout->setSpacing(0);
    controlLayout->setMargin(1);
    mpControl->setLayout(controlLayout);
    controlLayout->addWidget(mpCurrent);
    controlLayout->addWidget(mpTitle);
    QSpacerItem *space = new QSpacerItem(mpPlayPauseBtn->width(), mpPlayPauseBtn->height(), QSizePolicy::MinimumExpanding);
    controlLayout->addSpacerItem(space);
    controlLayout->addWidget(mpVolumeSlider);
    controlLayout->addWidget(mpVolumeBtn);
    controlLayout->addWidget(mpStopBtn);
    controlLayout->addWidget(mpBackwardBtn);
    controlLayout->addWidget(mpPlayPauseBtn);
    controlLayout->addWidget(mpForwardBtn);
    controlLayout->addWidget(mpOpenBtn);
    controlLayout->addWidget(mpEnd);

    connect(mpOpenBtn, SIGNAL(clicked()), SLOT(openFile()));
    connect(mpPlayPauseBtn, SIGNAL(clicked()), SLOT(togglePlayPause()));

    mIsReady = true;
//    connect(mpTimeSlider, SIGNAL(sliderMoved(int)), SLOT(seek(int)));
    connect(mpTimeSlider, SIGNAL(sliderPressed()), SLOT(seek()));
    connect(mpTimeSlider, SIGNAL(sliderReleased()), SLOT(seek()));
    connect(mpTimeSlider, SIGNAL(onLeave()), SLOT(onTimeSliderLeave()));
    connect(mpTimeSlider, SIGNAL(onHover(int,int)), SLOT(onTimeSliderHover(int,int)));
    QTimer::singleShot(0, this, SLOT(initPlayer()));
}
void MainWindow::initPlayer()
{
    connect(mpVolumeBtn, SIGNAL(clicked()), SLOT(showHideVolumeBar()));
    connect(mpVolumeSlider, SIGNAL(sliderPressed()), SLOT(setVolume()));
    connect(mpVolumeSlider, SIGNAL(valueChanged(int)), SLOT(setVolume()));
    connect(mpStopBtn, SIGNAL(clicked()), this, SLOT(stopUnload()));
    connect(mpForwardBtn, SIGNAL(clicked()), mpPlayer, SLOT(seekForward()));
    connect(mpBackwardBtn, SIGNAL(clicked()), mpPlayer, SLOT(seekBackward()));
    connect(mpPlayer, SIGNAL(seekFinished()), SLOT(onSeekFinished()));
    connect(mpPlayer, SIGNAL(error(QtAV::AVError)), this, SLOT(handleError(QtAV::AVError)));
    connect(mpPlayer, SIGNAL(started()), this, SLOT(onStartPlay()));
    connect(mpPlayer, SIGNAL(stopped()), this, SLOT(onStopPlay()));
    connect(mpPlayer, SIGNAL(paused(bool)), this, SLOT(onPaused(bool)));
    //    connect(mpPlayer, SIGNAL(speedChanged(qreal)), this, SLOT(onSpeedChange(qreal)));
    connect(mpPlayer, SIGNAL(positionChanged(qint64)), this, SLOT(onPositionChange(qint64)));

}
void MainWindow::stopUnload()
{
    mpPlayer->stop();
    mpPlayer->unload();
}
void MainWindow::handleError(const AVError &e)
{
    QMessageBox::warning(0, tr("Player error"), e.string());
}

void MainWindow::onStartPlay()
{
    mFile = mpPlayer->file(); //open from EventFilter's menu
    mTitle = mFile;
    if (!mFile.contains(QLatin1String("://")) || mFile.startsWith(QLatin1String("file://")))
        mTitle = QFileInfo(mFile).fileName();
    setWindowTitle(mTitle);

    mpPlayPauseBtn->setIcon(QIcon(QString::fromLatin1("./image/pause.png")));
    mpTimeSlider->setMinimum(mpPlayer->mediaStartPosition());
    mpTimeSlider->setMaximum(mpPlayer->mediaStopPosition());
    mpTimeSlider->setValue(0);
    mpTimeSlider->setEnabled(mpPlayer->isSeekable());
    mpEnd->setText(QTime(0, 0, 0).addMSecs(mpPlayer->mediaStopPosition()).toString(QString::fromLatin1("HH:mm:ss")));
    setVolume();

    QTimer::singleShot(3000, this, SLOT(tryHideControlBar()));
    mpRepeatA->setMinimumTime(QTime(0, 0, 0).addMSecs(mpPlayer->mediaStartPosition()));
    mpRepeatA->setMaximumTime(QTime(0, 0, 0).addMSecs(mpPlayer->mediaStopPosition()));
    mpRepeatB->setMinimumTime(QTime(0, 0, 0).addMSecs(mpPlayer->mediaStartPosition()));
    mpRepeatB->setMaximumTime(QTime(0, 0, 0).addMSecs(mpPlayer->mediaStopPosition()));
    mpRepeatA->setTime(QTime(0, 0, 0).addMSecs(mpPlayer->startPosition()));
    mpRepeatB->setTime(QTime(0, 0, 0).addMSecs(mpPlayer->stopPosition()));
    mCursorTimer = startTimer(3000);
}

void MainWindow::onStopPlay()
{
    if (mpPlayer->currentRepeat() < mpPlayer->repeat())
        return;
    mpPlayPauseBtn->setIcon(QIcon(QString::fromLatin1("./image/play.png")));
    mpTimeSlider->setValue(0);
    qDebug(">>>>>>>>>>>>>>disable slider");
    mpTimeSlider->setDisabled(true);
    mpTimeSlider->setMinimum(0);
    mpTimeSlider->setMaximum(0);
    mpCurrent->setText(QString::fromLatin1("00:00:00"));
    mpEnd->setText(QString::fromLatin1("00:00:00"));
    tryShowControlBar();
    toggleRepeat(false);
//    mRepeateMax = 0;
    killTimer(mCursorTimer);
    unsetCursor();
    if (m_preview)
        m_preview->setFile(QString());
}
void MainWindow::seek()
{
    mpPlayer->setSeekType(AccurateSeek);
    mpPlayer->seek((qint64)mpTimeSlider->value());
}
void MainWindow::onTimeSliderLeave()
{
    if (m_preview && m_preview->isVisible())
        m_preview->hide();
}
void MainWindow::onTimeSliderHover(int pos, int value)
{
    QPoint gpos = mapToGlobal(mpTimeSlider->pos() + QPoint(pos, 0));
    QToolTip::showText(gpos, QTime(0, 0, 0).addMSecs(value).toString(QString::fromLatin1("HH:mm:ss")));
    if (!m_preview)
        m_preview = new VideoPreviewWidget();
    m_preview->setFile(mpPlayer->file());
    m_preview->setTimestamp(value);
    m_preview->setWindowFlags(m_preview->windowFlags() |Qt::FramelessWindowHint|Qt::WindowStaysOnTopHint);
}
void MainWindow::onPaused(bool p)
{
    if (p) {
        qDebug("start pausing...");
        mpPlayPauseBtn->setIcon(QIcon(QString::fromLatin1("./image/play.png")));
    } else {
        qDebug("stop pausing...");
        mpPlayPauseBtn->setIcon(QIcon(QString::fromLatin1("./image/pause.png")));
    }
}
void MainWindow::showHideVolumeBar()
{
    if (mpVolumeSlider->isHidden()) {
        mpVolumeSlider->show();
    } else {
        mpVolumeSlider->hide();
    }
}
void MainWindow::tryShowControlBar()
{
    unsetCursor();
    if (mpTimeSlider && mpTimeSlider->isHidden())
        mpTimeSlider->show();
    if (mpControl && mpControl->isHidden())
        mpControl->show();
}
void MainWindow::toggleRepeat(bool r)
{
    mpRepeatAction->defaultWidget()->setEnabled(r); //why need defaultWidget?
    if (r) {
        mRepeateMax = mpRepeatBox->value();
    } else {
        mRepeateMax = 0;
    }
    if (mpPlayer) {
        mpPlayer->setRepeat(mRepeateMax);
    }
}
void MainWindow::setVolume()
{
    AudioOutput *ao = mpPlayer ? mpPlayer->audio() : 0;
    qreal v = qreal(mpVolumeSlider->value())*kVolumeInterval;
    if (ao) {
        if (qAbs(int(ao->volume()/kVolumeInterval) - mpVolumeSlider->value()) >= int(0.1/kVolumeInterval)) {
            ao->setVolume(v);
        }
    }
    mpVolumeSlider->setToolTip(QString::number(v));
    mpVolumeBtn->setToolTip(QString::number(v));
}
void MainWindow::openFile()
{
    QString file = QFileDialog::getOpenFileName(0, tr("Open a media file"));
    if (file.isEmpty())
        return;
    play(file);

}
void MainWindow::onPositionChange(qint64 pos)
{
    if (mpPlayer->isSeekable())
        mpTimeSlider->setValue(pos);
    mpCurrent->setText(QTime(0, 0, 0).addMSecs(pos).toString(QString::fromLatin1("HH:mm:ss")));
}
void MainWindow::togglePlayPause()
{
    if (mpPlayer->isPlaying()) {
        qDebug("isPaused = %d", mpPlayer->isPaused());
        mpPlayer->pause(!mpPlayer->isPaused());
    } else {
        if (mFile.isEmpty())
            return;
        if (!mpPlayer->isPlaying()){
            play(mFile);
        }
        else{
//            qDebug()<<"111111111111111111111111111111111111111\n";
            mpPlayer->play();
            mpPlayPauseBtn->setIcon(QIcon(QString::fromLatin1("./image/pause.png")));
       }
    }
}
void MainWindow::play(const QString &name)
{
    mFile = name;
    if (!mIsReady) {
        mHasPendingPlay = true;
        return;
    }
    mTitle = mFile;
    if (!mFile.contains(QLatin1String("://")) || mFile.startsWith(QLatin1String("file://"))) {
        mTitle = QFileInfo(mFile).fileName();
    }
    setWindowTitle(mTitle);
    mpPlayer->play(name);
}
void MainWindow::onSeekFinished()
{
    qDebug("seek finished at %lld", mpPlayer->position());
}
void MainWindow::setRepeateMax(int m)
{
    mRepeateMax = m;
    if (mpPlayer) {
        mpPlayer->setRepeat(m);
    }
}
void MainWindow::repeatAChanged(const QTime& t)
{
    if (!mpPlayer)
        return;
    mpPlayer->setStartPosition(QTime(0, 0, 0).msecsTo(t));
}
void MainWindow::repeatBChanged(const QTime& t)
{
    if (!mpPlayer)
        return;
    // when this slot is called? even if only range is set?
    if (t <= mpRepeatA->time())
        return;
    mpPlayer->setStopPosition(QTime(0, 0, 0).msecsTo(t));
}

说明下：Slider.h和Slider.cpp这个类所有代码我没动过，从QtAV代码中截取出来，有些槽函数未使用到（主要是是因为我怕以后可能要进行扩展，所以全部保存了下来），这个播放器我大概花了2~3天左右，包括搭环境、写代码、调试等，有不好的地方见谅，希望能帮到很多人！！！

我已将代码上传CSDN，欢迎下载！！！
链接：基于QtAV的简易播放器代码