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

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      #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();
      }