playercontrols.cpp

/****************************************************************************
**
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** BSD License Usage
** Alternatively, you may use this file under the terms of the BSD license
** as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of The Qt Company Ltd nor the names of its
**     contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "playercontrols.h"

#include <QBoxLayout>
#include <QSlider>
#include <QStyle>
#include <QToolButton>
#include <QComboBox>
#include <QAudio>

PlayerControls::PlayerControls(QWidget *parent)
    : QWidget(parent)
{
    m_playButton = new QToolButton(this);
    m_playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));

    connect(m_playButton, &QAbstractButton::clicked, this, &PlayerControls::playClicked);

    m_stopButton = new QToolButton(this);
    m_stopButton->setIcon(style()->standardIcon(QStyle::SP_MediaStop));
    m_stopButton->setEnabled(false);

    connect(m_stopButton, &QAbstractButton::clicked, this, &PlayerControls::stop);

    m_nextButton = new QToolButton(this);
    m_nextButton->setIcon(style()->standardIcon(QStyle::SP_MediaSkipForward));

    connect(m_nextButton, &QAbstractButton::clicked, this, &PlayerControls::next);

    m_previousButton = new QToolButton(this);
    m_previousButton->setIcon(style()->standardIcon(QStyle::SP_MediaSkipBackward));

    connect(m_previousButton, &QAbstractButton::clicked, this, &PlayerControls::previous);

    m_muteButton = new QToolButton(this);
    m_muteButton->setIcon(style()->standardIcon(QStyle::SP_MediaVolume));

    connect(m_muteButton, &QAbstractButton::clicked, this, &PlayerControls::muteClicked);

    m_volumeSlider = new QSlider(Qt::Horizontal, this);
    m_volumeSlider->setRange(0, 100);

    connect(m_volumeSlider, &QSlider::valueChanged, this, &PlayerControls::onVolumeSliderValueChanged);

    m_rateBox = new QComboBox(this);
    m_rateBox->addItem("0.5x", QVariant(0.5));
    m_rateBox->addItem("1.0x", QVariant(1.0));
    m_rateBox->addItem("2.0x", QVariant(2.0));
    m_rateBox->setCurrentIndex(1);

    connect(m_rateBox, QOverload<int>::of(&QComboBox::activated), this, &PlayerControls::updateRate);

    QBoxLayout *layout = new QHBoxLayout;
    layout->setContentsMargins(0, 0, 0, 0);
    layout->addWidget(m_stopButton);
    layout->addWidget(m_previousButton);
    layout->addWidget(m_playButton);
    layout->addWidget(m_nextButton);
    layout->addWidget(m_muteButton);
    layout->addWidget(m_volumeSlider);
    layout->addWidget(m_rateBox);
    setLayout(layout);
}

QMediaPlayer::PlaybackState PlayerControls::state() const
{
    return m_playerState;
}

void PlayerControls::setState(QMediaPlayer::PlaybackState state)
{
    if (state != m_playerState) {
        m_playerState = state;

        switch (state) {
        case QMediaPlayer::StoppedState:
            m_stopButton->setEnabled(false);
            m_playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
            m_playButton->click();
            break;
        case QMediaPlayer::PlayingState:
            m_stopButton->setEnabled(true);
            m_playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPause));
            break;
        case QMediaPlayer::PausedState:
            m_stopButton->setEnabled(true);
            m_playButton->setIcon(style()->standardIcon(QStyle::SP_MediaPlay));
            break;
        }
    }
}

float PlayerControls::volume() const
{
    qreal linearVolume =  QAudio::convertVolume(m_volumeSlider->value() / qreal(100),
                                                QAudio::LogarithmicVolumeScale,
                                                QAudio::LinearVolumeScale);

    return linearVolume;
}

void PlayerControls::setVolume(float volume)
{
    qreal logarithmicVolume = QAudio::convertVolume(volume,
                                                    QAudio::LinearVolumeScale,
                                                    QAudio::LogarithmicVolumeScale);

    m_volumeSlider->setValue(qRound(logarithmicVolume * 100));
}

bool PlayerControls::isMuted() const
{
    return m_playerMuted;
}

void PlayerControls::setMuted(bool muted)
{
    if (muted != m_playerMuted) {
        m_playerMuted = muted;

        m_muteButton->setIcon(style()->standardIcon(muted
                ? QStyle::SP_MediaVolumeMuted
                : QStyle::SP_MediaVolume));
    }
}

void PlayerControls::playClicked()
{
    switch (m_playerState) {
    case QMediaPlayer::StoppedState:
    case QMediaPlayer::PausedState:
        emit play();
        break;
    case QMediaPlayer::PlayingState:
        emit pause();
        break;
    }
}

void PlayerControls::muteClicked()
{
    emit changeMuting(!m_playerMuted);
}

qreal PlayerControls::playbackRate() const
{
    return m_rateBox->itemData(m_rateBox->currentIndex()).toDouble();
}

void PlayerControls::setPlaybackRate(float rate)
{
    for (int i = 0; i < m_rateBox->count(); ++i) {
        if (qFuzzyCompare(rate, float(m_rateBox->itemData(i).toDouble()))) {
            m_rateBox->setCurrentIndex(i);
            return;
        }
    }

    m_rateBox->addItem(QString("%1x").arg(rate), QVariant(rate));
    m_rateBox->setCurrentIndex(m_rateBox->count() - 1);
}

void PlayerControls::updateRate()
{
    emit changeRate(playbackRate());
}

void PlayerControls::onVolumeSliderValueChanged()
{
    emit changeVolume(volume());
}