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

hskoglund · wrote on 24 Aug 2020, 10:03

Hah, so it was a ~ that sent you on a wild goose chase!
(tildes can be a PITA, I remember tripping on them when trying to ssh into Ubuntu from Windows)
Anways, glad to hear its working now :-)

Jalpesh · wrote on 31 Aug 2020, 19:08

@hskoglund thank Man!

sudo apt remove qtchooser
sudo apt install libqt5gui5

boom.... its work

chEguy · 9 Jul 2020, 16:11

Guys I still am getting this error

qt.qpa.xcb: could not connect to display :0
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, xcb.
Aborted

BTW I am using Ubuntu20 on Windows10 with xcvsrv as X server

chEguy · C chEguy 7 Sept 2020, 16:04

I actually am not able to connect it to the display

Please help

hskoglund · wrote on 7 Sept 2020, 18:26

Hi just guessing but maybe the solution in this post will help you too.

Matriarch · 17 Jul 2021, 11:48

@Lengendary This is working solution for me, thank you

sudo apt-get install libxcb-xinerama0

aurelien · wrote on 12 Sept 2020, 07:31

I know it is considered as a good software to build good software, but the point is here:

When you follow an installation guide step by step and make everything correctly, and the stuff does not works, that just mean it have been made with foot (from the stuff to the documentation.)

Really for thus who do their best, but it just not works on Debian 10 without doing weird things that should not be done out of the installation documentation.

Good luck

Obed · wrote on 15 Sept 2020, 11:49

@Srinivas-Reddy Thanks. That helped me

Megan S · 22 Sept 2020, 06:45

Thanks for all the helpful info on the thread!!

I am attempting an anaconda environment creation... I don't have admin privileges on the system I'm working on. It's Ubuntu16.04.1 LTS (Xenial Xerus)"

The error I get is below. I'm assuming that because I'm using the anaconda install vs using apt-get, I can't just easily reinstall? It looks to me as if I'm missing the libxcb-xinerama.so.0 package. I checked qmake --version, the output shows Qt version 5.9.7

Thanks for any suggestions!

QLibraryPrivate::loadPlugin failed on "/export/research/analysis/human/jstephen/shared/programs/python/anaconda_072020/new/envs/mne21/lib/python3.8/site-packages/PyQt5/Qt/plugins/platforms/libqxcb.so" : "Cannot load library /export/research/analysis/human/jstephen/shared/programs/python/anaconda_072020/new/envs/mne21/lib/python3.8/site-packages/PyQt5/Qt/plugins/platforms/libqxcb.so: (libxcb-xinerama.so.0: cannot open shared object file: No such file or directory)"
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

$ qmake --version
QMake version 3.1
Using Qt version 5.9.7 in /export/research/analysis/human/jstephen/shared/programs/python/anaconda_072020/new/envs/mne21/lib

jsulm · wrote on 22 Sept 2020, 06:45

@Megan-S said in qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:

libxcb-xinerama.so.0: cannot open shared object file: No such file or directory

So do you have libxcb-xinerama.so.0?

mathsbloke · wrote on 17 Oct 2020, 17:46

@Srinivas-Reddy Many thanks, that got mine working too!

C0K01 · wrote on 5 Nov 2020, 17:52

@Srinivas-Reddy Many thanks!

Jimit Rupani · 28 Dec 2020, 17:14

@Advig said in qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:

export QT_DEBUG_PLUGINS=1
export PATH=$PATH:~/Qt/Tools/QtCreator/bin
libxcb dependency so https://unix.stackexchange.com/questions/338519/how-to-install-libxcb gave the solution.

sudo apt-get install libxcb-randr0-dev libxcb-xtest0-dev libxcb-xinerama0-dev libxcb-shape0-dev libxcb-xkb-dev

sudo apt-get install libxkbcommon-x11-dev

solved my problem for ubuntu 20.04. Tried reinstalling almost 3 times before the solution. Hope it helps someone

coffeesmoke · 29 Nov 2020, 10:03

So, Debian 10:

ldd -r <for example, home dir>/Qt/Tools/QtCreator/lib/Qt/plugins/platforms/libqxcb.so | grep libxcb-util

libxcb-util.so.1 => not found

Ok, continue...
sudo find /usr/lib | grep libxcb-util
...
libxcb-util.so.0.0.0
libxcb-util.so.0.0
libxcb-util.so.0
, but need
libxcb-util.so.1
Ok, Debian... :) Redy?
sudo ln -fs /usr/lib/x86_64-linux-gnu/libxcb-util.so.0.0.0 /usr/lib/x86_64-linux-gnu/libxcb-util.so.1.0.0
sudo ln -fs /usr/lib/x86_64-linux-gnu/libxcb-util.so.0.0.0 /usr/lib/x86_64-linux-gnu/libxcb-util.so.1.0
sudo ln -fs /usr/lib/x86_64-linux-gnu/libxcb-util.so.0.0.0 /usr/lib/x86_64-linux-gnu/libxcb-util.so.1

QtCreator start complete! :))))

stounhange7 · wrote on 23 Nov 2020, 18:11

@coffeesmoke thanks for the help. you revived my qt on debian 10

1init · wrote on 29 Nov 2020, 10:03

@coffeesmoke thank you for this i ran the debian 9 instructions after installing the updates and had this issue
i run devuan

Malachi · 14 Dec 2020, 21:28

That symlink seems a little risky. Two worries:

What happens when the actual v1+ of the actual libxcb-util attempts to install?
Are you 100% sure Qt Creator isn't depending on a different API? Seems like a dice roll

I admit though, it's better than nothing

EDIT: A few minutes of browsing https://gitlab.freedesktop.org/xorg/lib/libxcb-util/-/blob/master/NEWS suggests that no API changes are there and that symlinking is probably API compliant in this case. Funny that Debian is 6 years behind on this lib. No judging. I know they gotta test stuff. Just funny :)

SlySven · wrote on 14 Dec 2020, 21:28

Assuming that version 0 of something is a pre-first version release and that Devuan 3.0 "Beowulf" (systemd-less fork of Debian 10.0 "Buster") only has the 0.0.0 version then I guess symlinking the 0.0.0 to the 1.0.0 is the only chance we've got. I just got clobbered by this when running the Qt Creator updater from within the last version that was giving me Qt 5.15.1 that told me that there was an update available. It is a real PITA when it upgraded itself out of working...

... however this topic has worked for me.

BTW The Devuan libxcb-util 0.0.0 version libraries do date back to 20 Aug 2014!

beetree · 21 Dec 2020, 12:57

@coffeesmoke

As for Debian. The correct library is found as of Debian 11. Which at the moment is in testing.

Qt application fails to start on Debian 10 Buster because libqxcb.so requires missing libxcb-util.so.1

Symlink to a different library version is a possible workaround, but does not guarantee everything else works as expected, and as such ill advised.

saulesquivelg · wrote on 16 Dec 2020, 20:26

I had the same problem after installing QT in Ubuntu 18.04, I've solved it with sudo apt install libxcp-xinerama0