QTreeWidget Expanding individual Items from memory in C++

Question

I have a Qt QTreeWidget and I am trying to save the state of which header items were expanded so that when I refresh my tree with new information it can re expand the items that were previously expanded.

Each time an itemExpanded or itemCollapsed signal is emitted I catch it in a slot and save to a member boolean for that particular item to represent whether expanded is now true or false. This is my memory.

When refreshing the tree I clear the tree completely using

clear();

Next I collapse all the headers using

collapseAll();

Now I want to restore which items were expanded and set them to expanded using each boolean I have that represents whether the item was previously expanded or collapsed using

expandItem();

I'm not particularly sure how to get the index of the item from my boolean alone.

I would of thought that

indexOfTopLevelItem(0);

Would give me the index of my toplevelitem at position 0 and then using my boolean associated with position 0 I could then decide whether to expand the item?

This also doesn't solve my problem of wanting to do it to each 'boolean' I have representing each item in the tree.

Thanks in advance.

Answer 1

The itemExpanded() signal's parameter is a pointer to QTreeWidgetItem. With a pointer to QTreeWidgetItem, you can call QTreeWidget::indexOfTopLevelItem, which will return the index of the expanded item. If you just store it with your boolean, you should have enough information to restore the items' state after the content has been updated.