Can't see Items List of QComboBox, when use showFullScreen

Qingshui Kong

@mrjj Hi
Thank you for replying so quickly!

Yes, it is very odd.

I find there is one more widget doing the strange things. It is QDateTimeEdit. It acts the same with QComboBox.

What's more, even though I can't see dropdown list, I can select one item by clicking.

mrjj

@Qingshui-Kong
Hi
Would be possible to test with newer/newest version of Qt ?

Also, did full screen work at some point but stopped or this is from beginning ?

Im wondering if it could be some sort of gfx driver issue or font rendering issue.

Qingshui Kong

@mrjj
Hi,

I haven't install newer version of Qt. So I can't test it now. Could you help to test that?

Full screen doesn't work. At least, I haven't seen that it works. So I think this is from the beginning.

If it is some sort of gfx driver issue or font rendering issue, how could I confirm it and how could I fix it?

Thanks!

mrjj

@Qingshui-Kong
hi
well i tested with
https://www.dropbox.com/s/3hlqg2hqm22m3gu/testfullscreen.zip?dl=0
and it works as expected.
Could You try same sample ?

Well you can check if any new drivers are available for your gfx card if not already done. ( like from Intel or nvidia)

Qingshui Kong

@mrjj
Hi,

Thank you very much!

This sample works.

Maybe, my program is a little complex. I should debug my program to find out the problem.

mrjj

@Qingshui-Kong
Hi
ok, that is good news. \o/
Its just a normal bug then.
Do you start app at once in full screen or
you toggle it ? ( like sample)

Qingshui Kong

@mrjj
Hi

I start app at once in full screen. I use w.showFullscreen() in the main() function.

mrjj

@Qingshui-Kong
hi
ok, i tried with sample that way too but still there are items.
So it seems its something in the real app code.
if you just do // w.showFullscreen()
then there is items visible ?
How do you fill the items to the combobox. any chance they can be empty strings for some reason ?

Qingshui Kong

@mrjj
Hi,
Yes, there should be some bugs in my app code.

If I use w.show() in the main function, it works.

I am sure that I have fill the items to the combobox. And I can select them by clicking, even though I can't see them.

AndyS

This is a known limitation on Windows, I suggest you have a look at https://doc.qt.io/qt-5/windows-issues.html#fullscreen-opengl-based-windows as that describes the problem in more detail and gives a solution which you can use.

Qingshui Kong

@AndyS

Thanks very much!

Qingshui Kong

@AndyS

Hi AndyS,

Could you answer my another question?
Here is the link.
https://forum.qt.io/topic/95431/how-to-set-window-flags-for-qfiledialog

Thanks.