qt.qpa.xcb: could not connect to display qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.

Yash_r

@hskoglund @jsulm @SGaist
Checking to see if anyone can further assist me with this issue as I am not able to debug the code from the Qt creator because of this very issue.

I would be able to provide any more information needed to better understand the issue.

SGaist

How many Qt versions do you have on your device ?

Yash_r

@SGaist
As far as i can see in the Options -> Kits, i have only 5.12.1 version configured for Beaglebone black.
(

SGaist

I meant on the device itself.

Yash_r

@SGaist
I am using the latest Debian Bullseye distro which is pretty much the latest available (updated from Debian Buster as a clean install).

So, the device is new and only has the Qt5,12,1,

SGaist

And it's the one you cross-compiled ?

Yash_r

@SGaist
Yes, Qt5.12.1 is the only version i have installed on my PC and using it for cross-compilation to the BBB.

Is there something that I am missing or might've messed up?

SGaist

When starting directly on the BBB, do you use the same backend ?

Yash_r

@SGaist said in qt.qpa.xcb: could not connect to display qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:

do you use the same backend ?

Same backend?? Can you tell me what backend is being asked about?

@SGaist said in qt.qpa.xcb: could not connect to display qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:

When starting directly on the BBB

Also I cannot directly start Qtcreator on BBB, since i don't have it installed on the BBB, and only use the cross-compilation on the ubuntu system to compile and deploy the app to the BBB (and nothing else)....don't know if that makes sense.

SGaist

Backed: xcb, eglfs, etc.

No need for Qt Creator on your target, I meant literally starting your application on it, for example through the command line.

Yash_r

@SGaist
When i run, any app on the target, from the terminal, I see the following output on the terminal:

SGaist

So it looks like your X server installation is incomplete to run Qt applications with the xcb backend. I would start by fixing that.

Yash_r

@SGaist

Can you help me with how to fix the incomplete X server installation? Or help provide some resource which can be helpful?

jsulm

@Yash_r Install libxcb-xkb1 package on your target device

Yash_r

@jsulm
That package is already installed according to the apt-install as can be seen in the below image:

Also, when i try to run the app (as debian user) from the terminal, i get the following error:

jsulm

@Yash_r Why do you start it with sudo?! By default starting GUI apps with sudo is not allowed for security reasons.

Yash_r

@jsulm @SGaist
I tried running the app without the sudo, and i got the same 'XKeyboard' error as below:

SGaist

It looks like a warning rather than an error per se.

You might have to configure something on the X server side.