I’m not quite sure about your question but there is nothing that stops you from having multiple top-level widgets (widgets having no parent, thus becoming an independent window).

Ok, I can understand your idea. But I want to edit the widget in the designer because this is very convenient.

So, the difference would be: I want to create the QWidget when compiling, following your idea, it would be created at runtime.

Would be very nice if there is a way you can tell me :)

Hi,

sorry I do not 100% understand the problem.

Let me try to re formulate:

1. You want an application with several top level windows.
2. you want to design those windows with designer
3. All this si done during developement so no need to load *.ui files at runtime.

Is this correct? If yes, do it the same way as with one designer created file :-) Replace QWidget from Lukas example with your class names, that is it.

Thank you, this was a correct interpretation.
At first I just wanted to know how to add a new UI file to my project, it was File>New>Qt>Qt Designer Form>templates\forms>Main Window.
But do I really need “new QWidget” if the Widget as is exists in the file which I have already added to my pro file ?
And how to call the form (by its filename? )?, btw I named it mainwindow2.ui

Thank you for help, still learning.