How to code QT "dialog" wihtout using QTDesigner "form"?

[Anonymous_Banned275]

I do not know how else to say this -

I have an example project which APPEARS to create dialog WITHOUT using the QTDesiger "form". - the actual form seems to be coded .
I understand it is perfectly legal , but I cannot figure it out , in the existing code , how it is done.

Mrs Google is of no help.
This describes standard - create project using QTDesigner

https://forum.qt.io/topic/36768/resolved-create-a-base-project-to-show-a-simple-dialog-starting-from-an-empty-project

It would,l help me to have both dialog object with QTDesiigner form - standard - and another object where the "form " is done in code. - just to compare.
Any constructive help would be appreciated.

[JonB]

@AnneRanch
Anything you can do in Designer can be done in code. When you build Qt runs its uic processor on your .ui file to generate a ui_.....h file from it, which is C++ source code that is then compiled, so everything just comes down to code which you can write without Designer.

About the simplest QDialog code would look like:

#include <QApplication>
#include <QDialog>
#include <QLabel>
#include <QLayout>
#include <QPushButton>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    QDialog dialog;
    dialog.setGeometry(100, 100, 400, 400);
    QVBoxLayout layout;
    dialog.setLayout(&layout);
    QLabel label("This is a label");
    layout.addWidget(&label);
    QPushButton button("This is a button");
    layout.addWidget(&button);

    dialog.exec();
}

About the simplest example I could find among those supplied with Qt is https://doc.qt.io/qt-5/qtwidgets-tutorials-addressbook-part1-example.html. It uses a QWidget rather than a QDialog, but it has the complete project including .pro file at https://code.qt.io/cgit/qt/qtbase.git/tree/examples/widgets/tutorials/addressbook/part1?h=5.15.

[Anonymous_Banned275]

Thank you.
Your example will help me to figure out why a project which does not use QTDesigner to build the form won't compile as subdirs project.
My best guess it keeps "rebuilding " the form ( dialog) from code.