- Qt 5.5
- Qt Multimedia Widgets
- Media Player Example
- playlistmodel.cpp Example File
- Qt 5.5.1 Reference Documentation

# playlistmodel.cpp Example File

player/playlistmodel.cpp

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    ** This file is part of the examples of the Qt Toolkit.
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    #include "playlistmodel.h"

    #include <QFileInfo>
    #include <QUrl>
    #include <QMediaPlaylist>

    PlaylistModel::PlaylistModel(QObject *parent)
        : QAbstractItemModel(parent)
        , m_playlist(0)
    {
    }

    int PlaylistModel::rowCount(const QModelIndex &parent) const
    {
        return m_playlist && !parent.isValid() ? m_playlist->mediaCount() : 0;
    }

    int PlaylistModel::columnCount(const QModelIndex &parent) const
    {
        return !parent.isValid() ? ColumnCount : 0;
    }

    QModelIndex PlaylistModel::index(int row, int column, const QModelIndex &parent) const
    {
        return m_playlist && !parent.isValid()
                && row >= 0 && row < m_playlist->mediaCount()
                && column >= 0 && column < ColumnCount
            ? createIndex(row, column)
            : QModelIndex();
    }

    QModelIndex PlaylistModel::parent(const QModelIndex &child) const
    {
        Q_UNUSED(child);

        return QModelIndex();
    }

    QVariant PlaylistModel::data(const QModelIndex &index, int role) const
    {
        if (index.isValid() && role == Qt::DisplayRole) {
            QVariant value = m_data[index];
            if (!value.isValid() && index.column() == Title) {
                QUrl location = m_playlist->media(index.row()).canonicalUrl();
                return QFileInfo(location.path()).fileName();
            }

            return value;
        }
        return QVariant();
    }

    QMediaPlaylist *PlaylistModel::playlist() const
    {
        return m_playlist;
    }

    void PlaylistModel::setPlaylist(QMediaPlaylist *playlist)
    {
        if (m_playlist) {
            disconnect(m_playlist, SIGNAL(mediaAboutToBeInserted(int,int)), this, SLOT(beginInsertItems(int,int)));
            disconnect(m_playlist, SIGNAL(mediaInserted(int,int)), this, SLOT(endInsertItems()));
            disconnect(m_playlist, SIGNAL(mediaAboutToBeRemoved(int,int)), this, SLOT(beginRemoveItems(int,int)));
            disconnect(m_playlist, SIGNAL(mediaRemoved(int,int)), this, SLOT(endRemoveItems()));
            disconnect(m_playlist, SIGNAL(mediaChanged(int,int)), this, SLOT(changeItems(int,int)));
        }

        beginResetModel();
        m_playlist = playlist;

        if (m_playlist) {
            connect(m_playlist, SIGNAL(mediaAboutToBeInserted(int,int)), this, SLOT(beginInsertItems(int,int)));
            connect(m_playlist, SIGNAL(mediaInserted(int,int)), this, SLOT(endInsertItems()));
            connect(m_playlist, SIGNAL(mediaAboutToBeRemoved(int,int)), this, SLOT(beginRemoveItems(int,int)));
            connect(m_playlist, SIGNAL(mediaRemoved(int,int)), this, SLOT(endRemoveItems()));
            connect(m_playlist, SIGNAL(mediaChanged(int,int)), this, SLOT(changeItems(int,int)));
        }

        endResetModel();
    }

    bool PlaylistModel::setData(const QModelIndex &index, const QVariant &value, int role)
    {
        Q_UNUSED(role);
        m_data[index] = value;
        emit dataChanged(index, index);
        return true;
    }

    void PlaylistModel::beginInsertItems(int start, int end)
    {
        m_data.clear();
        beginInsertRows(QModelIndex(), start, end);
    }

    void PlaylistModel::endInsertItems()
    {
        endInsertRows();
    }

    void PlaylistModel::beginRemoveItems(int start, int end)
    {
        m_data.clear();
        beginRemoveRows(QModelIndex(), start, end);
    }

    void PlaylistModel::endRemoveItems()
    {
        endInsertRows();
    }

    void PlaylistModel::changeItems(int start, int end)
    {
        m_data.clear();
        emit dataChanged(index(start,0), index(end,ColumnCount));
    }