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

sheril

@Srinivas-Reddy
Thanks.

requinham

@Lengendary Thanks, this resolve the problem for me on Ubuntu 18.04 Qt 5.15.2

CoreDump

Environment: Ubuntu20.10; Qt 5.15.2, VirtualBox VM:

The solution provided by @Legendary no longer works, use this instead:

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

roboTURx

@coffeesmoke thanks a lot ~ this works for me

Deep61803

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

ibxcb-xinerama0

Thank you, This solution helped me also.

trimixotun

It's looks slightly outdated, but maybe it someone helps:

Debian 10 x86-64.
LXDE
Fresh net install Qt 5.12.10

Qtcreator first launch problem: "qt.qpa.plugin: Could not load the Qt platform plugin "xcb"".

Nothing from above helps at all. Qtcreator needs libxcb-util.so.1, but system has only libxcb-util.so.

Simple solution:

sudo ln -s /usr/lib/x86_64-linux-gnu/libxcb-util.so /usr/lib/x86_64-linux-gnu/libxcb-util.so.1

All work, folks.

wobl

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

sudo ln -s /usr/lib/x86_64-linux-gnu/libxcb-util.so /usr/lib/x86_64-linux-gnu/libxcb-util.so.1

Thanks a lot ... this is working for MX Linux too - but with a little correction:

sudo ln -s /usr/lib/x86_64-linux-gnu/libxcb-util.so.0.0.0 /usr/lib/x86_64-linux-gnu/libxcb-util.so.1

nileshmoodley

@Srinivas-Reddy Thank you very much - this solved it for me!

Jean-Noel

For me (on Debian), the only thing that worked was to completely uninstall Qt with Maintenance Tool, and install with "default" configuration.

ajlogo

The plugin problem started when I re-created an Anaconda env (PyQt5 and ubuntu) from a .yml file.
https://newini.wordpress.com/2020/08/13/how-to-solve-xcb-plugin-error-in-pyqt5/
Had the working answer for me:
sudo apt-get install qt5-default # For Ubuntu system

pixel_08

@SGaist hi,
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, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.
/bin/bash: line 133: 1745 Aborted (core dumped) python csv2txt.py

Then I added, export QT_DEBUG_PLUGINS=1
got error as,
QFactoryLoader::QFactoryLoader() checking directory path "/usr/local/bin/platforms" ...
Cannot load library /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so: (libxcb-util.so.1: cannot open shared object file: No such file or directory)
QLibraryPrivate::loadPlugin failed on "/builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so" : "Cannot load library /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so: (libxcb-util.so.1: cannot open shared object file: No such file or directory)"

and ran ldd /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so

linux-vdso.so.1 (0x00007ffc728e9000)
libQt5XcbQpa.so.5 => /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/../../lib/libQt5XcbQpa.so.5 (0x00007fda88aa2000)
libfontconfig.so.1 => /usr/lib/x86_64-linux-gnu/libfontconfig.so.1 (0x00007fda88a50000)
libfreetype.so.6 => /usr/lib/x86_64-linux-gnu/libfreetype.so.6 (0x00007fda88994000)
libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007fda88776000)
libQt5Gui.so.5 => /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/../../lib/libQt5Gui.so.5 (0x00007fda87e45000)
libQt5DBus.so.5 => /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/../../lib/libQt5DBus.so.5 (0x00007fda87bb7000)
libQt5Core.so.5 => /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/../../lib/libQt5Core.so.5 (0x00007fda873c1000)
libGL.so.1 => /usr/lib/x86_64-linux-gnu/libGL.so.1 (0x00007fda8732d000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fda8730c000)
libX11-xcb.so.1 => /usr/lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007fda87307000)
libxcb-icccm.so.4 => /usr/lib/x86_64-linux-gnu/libxcb-icccm.so.4 (0x00007fda87300000)
libxcb-image.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-image.so.0 (0x00007fda870f9000)
libxcb-shm.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-shm.so.0 (0x00007fda870f4000)
libxcb-util.so.1 => not found
libxcb-keysyms.so.1 => /usr/lib/x86_64-linux-gnu/libxcb-keysyms.so.1 (0x00007fda86ef1000)
libxcb-randr.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-randr.so.0 (0x00007fda86edf000)
libxcb-render-util.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-render-util.so.0 (0x00007fda86cdb000)
libxcb-render.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-render.so.0 (0x00007fda86cca000)
libxcb-shape.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-shape.so.0 (0x00007fda86cc5000)
libxcb-sync.so.1 => /usr/lib/x86_64-linux-gnu/libxcb-sync.so.1 (0x00007fda86cbb000)
libxcb-xfixes.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-xfixes.so.0 (0x00007fda86cb1000)
libxcb-xinerama.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-xinerama.so.0 (0x00007fda86cac000)
libxcb-xkb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb-xkb.so.1 (0x00007fda86c8e000)
libxcb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb.so.1 (0x00007fda86c62000)
libXext.so.6 => /usr/lib/x86_64-linux-gnu/libXext.so.6 (0x00007fda86a50000)
libX11.so.6 => /usr/lib/x86_64-linux-gnu/libX11.so.6 (0x00007fda8690f000)
libxkbcommon-x11.so.0 => /usr/lib/x86_64-linux-gnu/libxkbcommon-x11.so.0 (0x00007fda86904000)
libxkbcommon.so.0 => /usr/lib/x86_64-linux-gnu/libxkbcommon.so.0 (0x00007fda868c2000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fda868bd000)
libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007fda86737000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007fda865b4000)
libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007fda8659a000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fda863d9000)
libxcb-util.so.1 => not found
libgthread-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libgthread-2.0.so.0 (0x00007fda863d4000)
libglib-2.0.so.0 => /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0 (0x00007fda862b3000)
libexpat.so.1 => /lib/x86_64-linux-gnu/libexpat.so.1 (0x00007fda86276000)
libuuid.so.1 => /lib/x86_64-linux-gnu/libuuid.so.1 (0x00007fda8626d000)
libpng16.so.16 => /usr/lib/x86_64-linux-gnu/libpng16.so.16 (0x00007fda86234000)
libdbus-1.so.3 => /lib/x86_64-linux-gnu/libdbus-1.so.3 (0x00007fda861e1000)
libicui18n.so.56 => /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/../../lib/libicui18n.so.56 (0x00007fda85d46000)
libicuuc.so.56 => /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/../../lib/libicuuc.so.56 (0x00007fda8598e000)
libicudata.so.56 => /builds/sravani_detect/video_frames/venv/lib/python3.9/site-packages/PyQt5/Qt5/plugins/platforms/../../lib/libicudata.so.56 (0x00007fda83fab000)
/lib64/ld-linux-x86-64.so.2 (0x00007fda89001000)
libGLX.so.0 => /usr/lib/x86_64-linux-gnu/libGLX.so.0 (0x00007fda83f77000)
libGLdispatch.so.0 => /usr/lib/x86_64-linux-gnu/libGLdispatch.so.0 (0x00007fda83eba000)
libxcb-util.so.0 => /usr/lib/x86_64-linux-gnu/libxcb-util.so.0 (0x00007fda83cb1000)
libXau.so.6 => /usr/lib/x86_64-linux-gnu/libXau.so.6 (0x00007fda83aad000)
libXdmcp.so.6 => /usr/lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007fda838a7000)
libpcre.so.3 => /lib/x86_64-linux-gnu/libpcre.so.3 (0x00007fda83833000)
libsystemd.so.0 => /lib/x86_64-linux-gnu/libsystemd.so.0 (0x00007fda83790000)
libbsd.so.0 => /usr/lib/x86_64-linux-gnu/libbsd.so.0 (0x00007fda83776000)
librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007fda8376c000)
liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007fda83744000)
liblz4.so.1 => /usr/lib/x86_64-linux-gnu/liblz4.so.1 (0x00007fda83725000)
libgcrypt.so.20 => /lib/x86_64-linux-gnu/libgcrypt.so.20 (0x00007fda83607000)
libgpg-error.so.0 => /lib/x86_64-linux-gnu/libgpg-error.so.0 (0x00007fda835e2000)

what to do next?
Thank you!

SGaist

Install the package that provides "libxcb-util.so.1" on your system.

pixel_08

@SGaist
Thank you, Can we run PyQt5 applications in gitlab by setting up a pipeline?
Please clarify this.

SGaist

Do you mean run tests on your GUI in GitLab ?

pixel_08

@SGaist yes

SGaist

Yes you can, you have to use the offscreen backend though unless your runner provides adequate connection to an X server.

Srinivas Reddy

@Srinivas-Reddy This worked for me. Thank you.

steel357

@jarvis Hi jarvis,
I am also getting same problem
Got keys from plugin meta data ("webgl")
QFactoryLoader::QFactoryLoader() looking at "/home/vineeth/.local/lib/python3.8/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so"
Found metadata in lib /home/vineeth/.local/lib/python3.8/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so, metadata=
{
"IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
"MetaData": {
"Keys": [
"xcb"
]
},
"archreq": 0,
"className": "QXcbIntegrationPlugin",
"debug": false,
"version": 331520
}

Got keys from plugin meta data ("xcb")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/platforms" ...
loaded library "/home/vineeth/.local/lib/python3.8/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so"
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.
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, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.

Aborted (core dumped)

did u found the solution??

I am using Linux in windows(WSL)

steel357

@SGaist
@jarvis Hi guys,
I am also getting the same problem

Got keys from plugin meta data ("webgl")
QFactoryLoader::QFactoryLoader() looking at "/home/vineeth/.local/lib/python3.8/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so"
Found metadata in lib /home/vineeth/.local/lib/python3.8/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so, metadata=
{
"IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3",
"MetaData": {
"Keys": [
"xcb"
]
},
"archreq": 0,
"className": "QXcbIntegrationPlugin",
"debug": false,
"version": 331520
}

Got keys from plugin meta data ("xcb")
QFactoryLoader::QFactoryLoader() checking directory path "/usr/bin/platforms" ...
loaded library "/home/vineeth/.local/lib/python3.8/site-packages/PyQt5/Qt5/plugins/platforms/libqxcb.so"
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.
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, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, webgl, xcb.

Aborted (core dumped)

**did u found the solution??

I am using Linux in windows(WSL) and tried it normal ubuntu also getting same error**

SGaist

"qt.qpa.xcb: could not connect to display"

You should check the Windows documentation.