How to make QDialog transparent in windows 7/10 ?

QtNovie

I have below code
setStyleSheet("background:transparent;");
setAttribute(Qt::WA_TranslucentBackground);
ui->setupUi(this);
which gives me transparent window in linux. But the same gives black background in windows. How to achieve the transparency in windows also ?

mrjj

Hi
It would only work for me on win 7 if i set
setWindowFlag(Qt::FramelessWindowHint,true);
but then it looses its border/caption.

QtNovie

I don't know how we will solve this. I tried many solutions but all fails and partially fixed. Finally i reported an issue QTBUG-65969

mrjj

Hi
ok super.
I moved to linux so didn't try a lot but i also tried
palette but had no luck with Dialogs.

Devopia53

@QtNovie

Hi.
Now you can only use Win32 api with Qt for that.

6thC

I gave up.
https://bugreports.qt.io/browse/QTBUG-55955

https://bugreports.qt.io/browse/QTBUG-28214

I got this from support.

I wonder how I have never noticed that before. It seems to not clear the
buffer after moving. Strange flickering that occurs while moving is because
there is double (or triple) buffering where each buffer seems to have separate
copy of the view.

Note that transparency does not always work. Windows does not support
transparent OpenGL windows and Qt achieves this through DWM effects. DWM
effects can be disabled on some machines, which would lead to just a solid
black background. I am thinking this could even be a side effect of DWM and
maybe has nothing to do with Qt actually.

How ever, is there a reason why you want frames and a transparent background?
This does not happen if you do this to the Window (/ApplicationWindow and for
widget, there is similar flag):

flags: Qt.FramelessWindowHint

It got me thinking - no. I didn't need it that much.
It's a windows thing - I'm used to it disappointing me now.

I plan on supporting windows but pushing linux or linux/boot2qt solution.