Qt Reference Documentation

filelistmodel.cpp Example File

itemviews/fetchmore/filelistmodel.cpp
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 #include "filelistmodel.h"
 #include <QApplication>
 #include <QPalette>
 #include <QBrush>
 #include <QDir>

 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);

     fileList = dir.entryList();
     fileCount = 0;
     reset();
 }