QWidget subclass setSurfaceType(...)

EntropySink

I'd like to do Vulkan things in a widget that lives within a designer-composed, uic-generated ui.
This hits (apparent) problems along each path I have considered;

uic doesn't allow me to inject a QWidget::createWindowContainer()-created object among its generated boilerplate code, and
I haven't (yet?) found a way for a subclass of QWidget to influence the QSurface::SurfaceType of its window.
- I have tried (not exhaustively) to windowHandle()->setSurfaceType(QSurface::VulkanSurface) at a few different possibilities inside my subclass, but I'm absolutely sure I'm not holding it right. In bipolar fits, it keeps doing either nothing at all, or blowing up violently.

It seems I'm missing something trivial; any ideas?

(I also suspect that I am deeply misunderstanding what a QWindow really is; probably mentally typecasting it into an X11 window in order to imagine that each QWidget will have its own private, impervious rectangle to act within.)

EntropySink

Sometimes just asking the question brings the answer.
I added a plain QWidget 'receptacle' in the .ui, then in my own mainwindow code I foist a layout on it holding my vulkan-equipped subwidget.

  ui_->setupUi(this);
  auto* vw = new QVulkanWindow{};
  ...
  auto* layout = new QVBoxLayout{};
  layout->addWidget(QWidget::createWindowContainer(vw));
  ui_->receptacle->setLayout(layout);