QFileSystemModel sorting DirsFirst

Question

How do you do to sort a QFileSystemModel with QDir::DirsFirst like in QDirModel? The QFileSystemModel does not have a setSorting method.

Answer 1

As far as I can tell, you can't (in Qt4).

The default sort order (by the "name" column), or sorting by size behaves like QDir::DirsFirst (or DirsLast if in reverse order for ), but sorting by time or type doesn't treat directories differently from ordinary files.

The QFileSystemModel doesn't expose an API for changing the sort order, and I don't see any opportunity for influencing it in the QFileSystemModel code.

(I don't see anything in the current Qt5 docs to indicate that this has changed, but those aren't final and I haven't looked very closely.)

Answer 2

Maybe somebody will need this. I have implemented directories first sorting using QSortFilterProxyModel for QFileSystemModel as Kuba Ober mention in comment. Might be not perfect yet, but still right direction.

bool MySortFilterProxyModel::lessThan(const QModelIndex &left, const QModelIndex &right) const
{
    // If sorting by file names column
    if (sortColumn() == 0) {
        QFileSystemModel *fsm = qobject_cast<QFileSystemModel*>(sourceModel());
        bool asc = sortOrder() == Qt::AscendingOrder ? true : false;

        QFileInfo leftFileInfo  = fsm->fileInfo(left);
        QFileInfo rightFileInfo = fsm->fileInfo(right);


        // If DotAndDot move in the beginning
        if (sourceModel()->data(left).toString() == "..")
            return asc;
        if (sourceModel()->data(right).toString() == "..")
            return !asc;

        // Move dirs upper
        if (!leftFileInfo.isDir() && rightFileInfo.isDir()) {
            return !asc;
        }
        if (leftFileInfo.isDir() && !rightFileInfo.isDir()) {
            return asc;
        }
    }

    return QSortFilterProxyModel::lessThan(left, right);
}