qt5base-lts/examples/widgets/itemviews/fetchmore/filelistmodel.cpp
Friedemann Kleint 2393a40ccd Rewrite the fetchmore example
- Start in root folder so that large directories (/bin/, Windows)
  are easily reachable
- Remove the line edit and navigate by double clicking instead
  since this is more in line with expectations
- Use a QPlainTextEdit for logging
- Make the log message more informative
- Add icons

Change-Id: Ia3cd7fc143efef80772923291f0b711913aa47be
Reviewed-by: Paul Wicking <paul.wicking@qt.io>
2021-04-23 12:43:28 +00:00

143 lines
4.4 KiB
C++

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#include "filelistmodel.h"
#include <QGuiApplication>
#include <QDir>
#include <QPalette>
static const int batchSize = 100;
FileListModel::FileListModel(QObject *parent)
: QAbstractListModel(parent)
{}
//![4]
int FileListModel::rowCount(const QModelIndex &parent) const
{
return parent.isValid() ? 0 : fileCount;
}
QVariant FileListModel::data(const QModelIndex &index, int role) const
{
if (!index.isValid())
return {};
const int row = index.row();
if (row >= fileList.size() || row < 0)
return {};
switch (role) {
case Qt::DisplayRole:
return fileList.at(row).fileName();
case Qt::BackgroundRole: {
const int batch = row / batchSize;
const QPalette &palette = QGuiApplication::palette();
return (batch % 2) != 0 ? palette.alternateBase() : palette.base();
}
case Qt::DecorationRole:
return iconProvider.icon(fileList.at(row));
}
return {};
}
//![4]
QFileInfo FileListModel::fileInfoAt(const QModelIndex &index) const
{
return fileList.at(index.row());
}
//![1]
bool FileListModel::canFetchMore(const QModelIndex &parent) const
{
if (parent.isValid())
return false;
return (fileCount < fileList.size());
}
//![1]
//![2]
void FileListModel::fetchMore(const QModelIndex &parent)
{
if (parent.isValid())
return;
const int start = fileCount;
const int remainder = int(fileList.size()) - start;
const int itemsToFetch = qMin(batchSize, remainder);
if (itemsToFetch <= 0)
return;
beginInsertRows(QModelIndex(), start, start + itemsToFetch - 1);
fileCount += itemsToFetch;
endInsertRows();
emit numberPopulated(path, start, itemsToFetch, int(fileList.size()));
}
//![2]
//![0]
void FileListModel::setDirPath(const QString &path)
{
QDir dir(path);
beginResetModel();
this->path = path;
fileList = dir.entryInfoList(QDir::NoDot | QDir::AllEntries, QDir::Name);
fileCount = 0;
endResetModel();
}
//![0]