One major difference I have found is that KConcatenateRowsProxyModel
will check if sourceModel exists when mapping from/to sourceModel, but
QConcatenateTablesProxyModel won't. So if QConcatenateTablesProxyModel
doesn't receive `rowsRemoved` signal from sourceModel,
QConcatenateTablesProxyModel will crash the program.
For example:
# KConcatenateRowsProxyModel
```cpp
QModelIndex KConcatenateRowsProxyModel::index(int row, int column, const
QModelIndex &parent) const
{
if (row < 0) {
return {};
}
if (column < 0) {
return {};
}
int sourceRow;
QAbstractItemModel *sourceModel = d->sourceModelForRow(row,
&sourceRow);
if (!sourceModel) {
return QModelIndex();
}
return mapFromSource(sourceModel->index(sourceRow, column, parent));
}
```
# QConcatenateTablesProxyModel
```cpp
QModelIndex QConcatenateTablesProxyModel::index(int row, int column,
const QModelIndex &parent) const
{
Q_D(const QConcatenateTablesProxyModel);
Q_ASSERT(hasIndex(row, column, parent));
if (!hasIndex(row, column, parent))
return QModelIndex();
Q_ASSERT(checkIndex(parent,
QAbstractItemModel::CheckIndexOption::ParentIsInvalid)); // flat model
const auto result = d->sourceModelForRow(row);
Q_ASSERT(result.sourceModel);
return mapFromSource(result.sourceModel->index(result.sourceRow,
column));
}
```
