filelistmodel.cpp Example File | Qt Widgets 5.12.12

- Qt 5.12
- Qt Widgets
- Fetch More Example
- filelistmodel.cpp Example File
- Qt 5.12.12 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);

         if (itemsToFetch <= 0)
             return;

         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();
     }