incremental loading in table view without canFetchMore() and fetchMore()

user4592357

i'm using a library which is based on qt.
the library has a table model/view implementation.
i need incremental populating for my table. however they do not have canFetchMore() and fetchMore() implemented.

in what ways can i implement lazy loading anyways?

one option i could think of was this:
i have the following variables: chunkRows - i want to retrieve this many rows at a time, m_currRowCount - the number of row currently loaded

set initial row count = chunkRows
in data() i do this check:

if (index.row() + chunkRows >= m_currRowCount)
    m_currRowCount += chunkRows;

...
return the data;

this approach doesn't work. in my table i get only the first chunkRows items.

please help :(

SGaist

Hi,

What do you mean by "they do not have" ?
What kind of model are you using ?

user4592357

@SGaist
i mean if those methods were implemented, i could make use of those for implementing lazy loading.
the model is derived from QAbstractTableModel, this is a part of data(), where m_pModel is a vector of vectors:

QVariant TableModel::data(const QModelIndex& index, int role) const
{
	int nRow = index.row();
	int nCol = index.column();
	if (nRow < 0 || nRow >= m_pModel->getRowCount() || nCol < 0 || nCol >= m_pModel->getColumnCount())
		return QVariant();

	if (role == Qt::DisplayRole)
	{
		QString sStr;
		m_pModel->getText(nRow, nCol, sStr);
		return sStr;
	}
        ....

i tried to increase the row count in m_pModel->getRowCount() implementation, but i guess the problem why that idea doesn't work is that the actual data isn't called for those increased rows, therefore, m_pModel->getText() isn't called either.