Mouse wheel event's angleDelta().y() always 0 with Alt key modifier

Tobias Megies megies at
Fri Nov 25 09:26:33 GMT 2022

Oh, should've thought of that. Thanks a lot for the quick help.

And ah, looking at that second bug report you listed (sorry, I didn't 
find these looking for previous reports), I realize I also used to have 
"delta()" and just followed the recommendations to replace it with 



On 25/11/2022 10:10, Florian Bruhin wrote:
> On Fri, Nov 25, 2022 at 10:01:39AM +0100, Tobias Megies wrote:
>> When Alt key is held down, mouse wheel events always report 0 for
>> "angleDelta().y()", i.e. it is impossible to tell in which direction the
>> mouse wheel was scrolled. Not sure if Alt is the only affected modifier, in
>> any case some other common keys like shift or control are not affected.
> It's a Qt problem, or rather probably intended Qt feature.
> Pressing Alt and scrolling leads to a horizontal scroll:
> Florian

EMail: tobias.megies at

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