Stack of views or generate on need? - performance

Question

Let's suppose, I'm creating a image editor, something like Photoshop, but simplier in Qt.
I got next problem - I have list of items and I can select only one of them at a time. Each item got QWidget which should be shown in MainWindow. The question is - should I create them(widgets) when I select item or should I just manage visibility of this widgets. Currently, I got the second solution - when item selected, I set the visibility of QWidget to true, and hide current widget. What is better in case of performance? I'm new to Qt, don't which practice is better to use in such case.
For better understanding - attaching a picture with sidebar and place for QWidget(blurred woman)
Disclaimer: It's not a opinion question - I'm asking about best practice in Qt and performance in each case. Thanks.

Answer 1

Here is an example using QListWidget and QListWidgetItem controlling the QStackedWidget:
// Stacked widget
QStackedWidget *pStackedWidget = new QStackedWidget();
// Creating widget list
QListWidget *pListWidget = new QListWidget();
connect(pListWidget, &QListWidget::itemSelectionChanged,
[pStackedWidget, pListWidget]() {
pStackedWidget->setCurrentIndex(
pListWidget->currentItem()->data(Qt::UserRole)
);
}
);
// Populating widget list with items
QListWidgetItem *pItem = new QListWidgetItem();
pListWidget->addItem(pItem);
pItem->setItemWidget(pItem, pWidget);
pItem->setData(Qt::UserRole, 0 /* widget index on stacked layout */);
Visibility of the widgets on the right is controlled by the QStackedWidget. Corresponding widget index is set upon selection change in the QListWidget.
Widget index can be stored in custom user data assigned to corresponding QListWidgetItem.