Insert Various GTKWidgets into a dlg_window

[Rui Pedro Caldeira <rpcaldeira outlook com>]

Hello Again, I have another problem.

I have all sorts os GTKWidgets (buttons, labels, comboboxes,...) and a
dlg_window.

And I would like to know how I can put all those widgets in the dlg_window
and set their size and position in the window.

Thanks in Advance and Best Regards,
Rui