Hellow All!

I use QMainWindow and menuBar() member.
Also I use adjustSize() for my MainWindow!!!
After compile and run I get TWO menubars (probably because of adjustSize()):
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| File | Edit | View |
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| Tools | Help |
-----------------

But I want to get ONE menubar, i.e.
-------------------------------------
| File | Edit | View | Tools | Help |
-------------------------------------

How to implement it?