Qt5 Embedded Framebuffer Poor GUI

[DarCom]

Hi.
Would someone please tell me why there are some graphic problems for framebuffer qt running on the embedded devices?
As an example, the title bar doesn't show anything or you can't drag a new window which is opened by the main window.
Another one is the bad shape of circle slider same as the picture in the link below.
https://www.google.com/imgres?imgurl=http://doc.qt.io/qt-5/images/sliders-example.png&imgrefurl=http://doc.qt.io/qt-5/qtwidgets-widgets-sliders-example.html&h=248&w=657&tbnid=cyJkBbbVVwT39M:&docid=ZoC_2IxLWtIOwM&ei=TjB1Vp-jI4iKU8SHh8AK&tbm=isch
These problems doesn't exist for qt4.

[SGaist]

Hi and welcome to devnet,

That's not graphics problem. With Qt 4 the only option you had for embedded was QWS a.k.a the Qt Windowing System. With Qt 5.5, the default for non xcb backend is "one app fullsceen". If you need window management without Xorg, you should look for Wayland which is also supported as backend by Qt 5.

[DarCom]

Hi.
Thanks a lot SGaist.
I'm new to Qt, so would you please explain more.
I'm using Linux Framebuffer and -eglfs switch that the quality of what is shown is not satisfying like the bad shape of widgets as slider.
1- So as you said it is ok. yes?
2- Using Wayland would the quality be ok? and is it run on Linux Framebuffer?
Thanks a lot.

[SGaist]

Again, it's not a quality question. You're expecting window decoration but have no window manager.

1. See the Qt for Embedded Linux for more details about how an application will be shown with the various plugins.
2. Wayland and the corresponding Qt backend will get you window management.

[DarCom]

I really thank you dear SGaist.
So, as i understood, even the different shape of a widget from what is in qt-creator is the responsibility of the window manager.

[SGaist]

If you are referring to the image you pointed from the doc, it's a snapshot from an old KDE. The window style and decoration will depend on the OS you'll be running your application on and the window manager used (if any).

If you want more control over how your UI looks like, you should consider using QML and QtQuick 2.0