Clear QTreeView selection when focus is outside its geometry

[Lurkki]

I have the following code inside my QTreeView derived class. Its purpose is to clear the QTreeView's selection when an outside widget is focused, but not when the widget is a delegate editor of the QTreeView.

auto app = static_cast<QApplication *>(QApplication::instance());
connect(app, &QApplication::focusChanged, [=](QWidget *old, QWidget *now) {
	if (now && !this->isAncestorOf(now)) {
		clearSelection();
	}
});

This code works fine when the delegate is a slider, but when the delegate is a QComboBox, the popup is not considered a child of the QTreeView and the selection is cleared unintentionally. Is there some other way to achieve this?

[Lurkki]

Came up with the following hack to identify when a delegate QComboBox gets focus:

auto app = static_cast<QApplication *>(QApplication::instance());
connect(app, &QApplication::focusChanged, [=](QWidget *old, QWidget *now) {
	auto newTypeStr = now->metaObject()->className();
	auto isComboBox = QString{newTypeStr} == QString{"QComboBoxListView"};
	if (now && !this->isAncestorOf(now) && !isComboBox) {
		clearSelection();
	}
});

This works for my purposes but there's probably a less hacky way to do this.