Removing rows

[indifference]

Hello all,

I'm making my own model to work with a QTableView, by subclassing QAbstractTableModel.
The table will have to work with many rows.
Everything works well, except when I try to remove the selected rows in the table.

This is the removeRows of the model:

bool SubViewerModel::removeRows( int position, int rows/*,
	const QModelIndex& parent*/ )
{
	beginRemoveRows( QModelIndex(), position,
		position + rows-1 );
 
	for ( int row = 0; row < rows; ++row )
		subtitles->removeAt( position );
 
	endRemoveRows();
 
	return true;
}

bool SubViewerModel::removeRows( int position, int rows/*,
	const QModelIndex& parent*/ )
{
	beginRemoveRows( QModelIndex(), position,
		position + rows-1 );

	for ( int row = 0; row < rows; ++row )
		subtitles->removeAt( position );

	endRemoveRows();

	return true;
}

To copy to clipboard, switch view to plain text mode 

and this is how the function is called:

void MainWindow::deleteSelected()
{
	QItemSelectionModel *selModel =
		subViewer->selectionModel();
 
	QModelIndexList indexes =
		selModel->selectedRows();
 
	foreach ( QModelIndex index, indexes )
		subViewerModel->removeRows( index.row(), 1 );
 
	setWindowModified( true );
}

void MainWindow::deleteSelected()
{
	QItemSelectionModel *selModel =
		subViewer->selectionModel();

	QModelIndexList indexes =
		selModel->selectedRows();

	foreach ( QModelIndex index, indexes )
		subViewerModel->removeRows( index.row(), 1 );

	setWindowModified( true );
}

To copy to clipboard, switch view to plain text mode 

If I select just one row, this row is deleted correctly, but I select various rows it will delete other rows that aren't selected.
Other problem is that deleting a great number of rows takes a long time...

Any sugestions to solve this?

Thanks!

[wysota]

Try removing rows from the end and not from the beginning (in the second snippet), because you're invalidating higher rows if you remove lower ones - imagine you have to remove rows 8 and 10 (out of 10 available) - if you remove row "8", then a total of 9 rows remain, causing row "10" to be invalid. You'll have to correct your removeRows() implementation because of the same reason as well...