Deselect *visually* at start of program

GKLC

I have a couple of QTreeWidgets in my UI, which I fill when I init my MainWindow (Creation Process: Construct -> Init -> Show) then I always get a ghost selection in all TWs.

When I fill the data into the TWs, I surround it with:

ui->itemList->clear(); 
ui->itemList->clearSelection();
ui->itemList->blockSignals(true);
// Fill data
ui->itemList->blockSignals(false);

(itemList = one of my TWs)

While clearSelection does clear the selection for the code (ui->itemTree->selectedItems().isEmpty()) it does not do that visually

The item looks selected, but isn't according to the code

bool noItemSel = ui->itemList->selectedItems().isEmpty();

This variable gets used to enable/disable certain buttons which should only work if an item is selected:

    ui->pbItemAdd->setDisabled(noTreeRights);
    ui->pbItemEdit->setDisabled(noItemSel || noTreeRights);
    ui->pbItemDelete->setDisabled(noItemSel || noTreeRights);

these buttons, shown here

get disabled, noTreeRights is false, as seen by the add button, so that one doesnt cause the issue of disabling. Theres a lot of other loading done when someone selects an Item, so I'd rather keep the tree widget unselected than selecting the first item

So how do I remove that visual selection?

Axel Spoerl

@GKLC
Thanks. Am I overlooking something? I don’t find a question in your post!

GKLC

@Axel-Spoerl I added the obvious question now.

J.Hilk

@GKLC that item is probably the "currentItem"
and since your selection mode is not NoSelection the item is also "selected" aka highlighted

GKLC

@J-Hilk I did ui->itemList->setCurrentItem(nullptr) now, and it still is highlighted

JonB

@GKLC
While you wait for an answer, what about a bit more detective work?

Move the clearSelection() to after the blockSignals() and data filling?
Can you temporarily comment out the blockSignals(), does that change behaviour?
Try selecting a different item in code. (Note: I think that requires changing the selection, not the currrent item.) Does the blue item move?
Is there any chance the first item in the list gets auto-/re-selected when first shown, independent of your code setting (I don't know)?
Try moving any selecting or deselecting code into a slot executed on a QTimer::singleShot() with a delay of 0 or small to execute after your filling code. Does that work?

GKLC

@JonB First 3 things do nothing, whether all together or singularly, the first item still is highlighted but not selected, which seems to confirm the 4th item that you suggested. The first item gets highlighted, though not selected (debugger confirms)

Axel Spoerl

First of all, as @J-Hilk pointed out, disable selections by
myTreeview->setSelectionMode(QAbstractItemView::NoSelection);

Nothing can be selected from now on.
What may look a bit like a selection is the currentItem.
That should not be highlighted, unless the tree widget has focus.
It is usually rendered with a visible frame, indicating that the frame can be moved with the up/down keys and the item can be expanded/collapsed with the left/right keys.

GKLC

@Axel-Spoerl I've tried setting the current item to a nullptr, which didn't help

I do need to be able to set a selection (SingleSelection specifically), at the start of the program however, I don't want anything selected, as it makes it confusing for users.

Its also definitely a selection if the current item only has that frame, that is, if the selected item is the highlighted blue item shown in the picture

JonB

@GKLC
By now I suggest you produce a 20-odd line standalone minimal example. Reduce to absolute least which produces behaviour. May not apply to you, but 50% of the time we ask for this the OP discovers the issue. Try for yourself just starting anew from a QTreeWidget.