Qt 5.9 | Qt Multimedia | Media Player Example | playlistmodel.cpp Example File

Qt 5.9.4 Reference Documentation

# playlistmodel.cpp Example File

multimediawidgets/player/playlistmodel.cpp

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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));
      }