filelistmodel.cpp Example File | Qt Widgets 5.6

Qt 5.6 | Qt Widgets | Fetch More Example | filelistmodel.cpp Example File

Qt 5.6.2 Reference Documentation

# filelistmodel.cpp Example File

itemviews/fetchmore/filelistmodel.cpp

      /****************************************************************************
      **
      ** Copyright (C) 2015 The Qt Company Ltd.
      ** Contact: http://www.qt.io/licensing/
      **
      ** This file is part of the examples of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** 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 "filelistmodel.h"

      #include <QApplication>
      #include <QBrush>
      #include <QDir>
      #include <QPalette>

      FileListModel::FileListModel(QObject *parent)
          : QAbstractListModel(parent)
      {
      }

      int FileListModel::rowCount(const QModelIndex & /* parent */) const
      {
          return fileCount;
      }

      QVariant FileListModel::data(const QModelIndex &index, int role) const
      {
          if (!index.isValid())
              return QVariant();

          if (index.row() >= fileList.size() || index.row() < 0)
              return QVariant();

          if (role == Qt::DisplayRole) {
              return fileList.at(index.row());
          } else if (role == Qt::BackgroundRole) {
              int batch = (index.row() / 100) % 2;
              if (batch == 0)
                  return qApp->palette().base();
              else
                  return qApp->palette().alternateBase();
          }
          return QVariant();
      }

      bool FileListModel::canFetchMore(const QModelIndex & /* index */) const
      {
          if (fileCount < fileList.size())
              return true;
          else
              return false;
      }

      void FileListModel::fetchMore(const QModelIndex & /* index */)
      {
          int remainder = fileList.size() - fileCount;
          int itemsToFetch = qMin(100, remainder);

          beginInsertRows(QModelIndex(), fileCount, fileCount+itemsToFetch-1);

          fileCount += itemsToFetch;

          endInsertRows();

          emit numberPopulated(itemsToFetch);
      }

      void FileListModel::setDirPath(const QString &path)
      {
          QDir dir(path);

          beginResetModel();
          fileList = dir.entryList();
          fileCount = 0;
          endResetModel();
      }