Track selection in QListWidget after undo/redo operations

[gabello306]

I have a QListWidget containing anywhere from 1 to 511 QListWidgetItems. I can add a new item and perform an undo and the new item is removed and a redo to add it back. This is done by saving the state of the vector containing all the QListWidgetItems. I perform the undo/redo by the following:

QlistWidget->clear();

and then reloading the data from the vector.

The problem is if there are selected items in the QListWidget. The selected items must be tracked in the undo/redo operations. I do save the selected items into a QList before clearing the QlistWidget. The problem is re-selecting the item after a redo. Since I clear the list and reload it the QListWidgetItem saved doesn't match the new list so it selects the wrong item in the QListWidget.

I save the selected items by doing the following:

QList<QListWidgetItems*> selectedIndices = QListWidget->selectedItems();

then clear the QListWidget:

QListWidget->clear();

reload the QListWidget and then set the selected items:

for (QListWidgetItems *items : selectedIndices )
{
    QListWidget->setCurrentItem(items);
}

[JonB]

@gabello306
But your selectedIndices does not hold indices! Don't save pointers to anything, and not the whole QListWidgetItem. Save indexes, or "unique key" if it's appropriate and unique. I don't know whether with QModelIndexList QListView::selectedIndexes() you can save and reuse a QModelIndex, quite possibly not, but since you have a simple list you can just save an int of its index. Of course you also need to restore sort order if that is dynamic....