- Qt 5.5
- Qt Widgets
- Fetch More Example
- filelistmodel.cpp Example File
- Qt 5.5.1 Reference Documentation

# filelistmodel.cpp Example File

itemviews/fetchmore/filelistmodel.cpp

    /****************************************************************************
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    ** This file is part of the examples of the Qt Toolkit.
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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();
    }