Problems with QML Style change from Qt5 to Qt6

[Kenz Dale]

I am upgrading a Qt5 app to Qt6. Everything is fine, except for the fact that the styles are weird and off.

This is how it used to look:

This is how it looks now:

Button text placements are wrong, the background color has changed, I'm getting a ton of The current style does not support customization of this control warning messages, etc...

Before I manhandle this back into shape, is there a simple Style setting I'm overlooking in moving from Qt5 to Qt6? I've tried a variety of import QtQuick.Controls..., and import QtQuick.Controls.Basic 2.15 gives the most similar results, although the colors are still inverted and button sizes still are subtly adjusted.

[JoeCFD]

@Kenz-Dale I feel the same way. There are a lot of changes in Qt6. Better to use the latest Qt6. Otherwise, there could be even more changes. If you have a product made from Qt5, do not rush to upgrade to Qt6.

[GrecKo]

@Kenz-Dale That happens because you didn't specify an explicit Style for your app.

In Qt 5 the default style was the aptly named Default Style. In Qt 6, it's platform dependent. So if you are on macOs, it will be the macOs Style.

You can specify the style to be the Basic Style. If you want to use compile time selection and not runtime selection, make sure you don't import QtQuick.Controls but only import QtQuick.Controls.Basic.

[Kenz Dale]

@GrecKo Thanks, that helped a ton.
Adding

#include <QQuickStyle>
.
.
.
int main(int argc, char *argv[]) {
   .
   .
   .
   // Set QML style. Could be Material, Universal, Basic, etc... Doing
   // it here sets it app-wide.
   QQuickStyle::setStyle("Basic");
   .
   .
   .
}

was exactly what I needed.