QTableView / QStandardItemModel update without losing selection / sort order

Question

Currently I want to update row items in a QStandardItemModel without losing the sort order and row selection in the respective QTableView.

I have tested two approaches:

Clearing the model by clear() and re-adding the rows "destroys" everything including headers.
Removing and re-adding all rows keeps the headers, but still "destroys" selection and sort order.

I could try to manually to a) remove all rows no longer required and then b) update the items of the changed rows. But is there no easier way?

have you tried using QProxyModel? The docs now say that it is outdated, but may serve your purpose — friendzis, Aug 06 '12 at 12:54
I do not see how this would help me. I could update all data on the proxy first, but then? What's the basic idea? — Horst Walter, Aug 06 '12 at 14:15
Proxy should handle selections and sort order and data model just provide the data — friendzis, Aug 06 '12 at 15:38

score 4 · Accepted Answer · edited Feb 02 '17 at 13:56

I don't know, how you sorted your data before the update, but please take a look at the QTableView's sortByColumn() function.

As for the selection, if it still keeps disappearing, you can manually put back your selection, where it should be by:

// You access the selected index when the editing starts
QModelIndex index = table->selectionModel()->currentIndex();

//Later when you finished editing, you can select it again
table->selectionModel()->select(index, QItemSelectionModel::Select);

More about this:

score 1 · Answer 2 · answered Aug 06 '12 at 11:57

You can either remove the rows no longer required and add the new ones or manually remember the sort order and which items were selected before clearing. I.e. assign a unique ID (one can use setData() with a custom role for that), retrieve that before clearing from the selected items, and reapply the selection after recreating the items.

QTableView / QStandardItemModel update without losing selection / sort order

2 Answers2