qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
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@SGaist
Me?That might be the problemWhen I point the Qt plugin path, 'xcb' couldn't be found
sugon@EC:~$ ~/QtProject/build-Test-Qt_6_3_1_in_PATH_Qt6_3_1-Debug/Test
qt.qpa.plugin: Could not find the Qt platform plugin "xcb" in "/home/sugon/Software/Qt6.3.1/plugins/platforms/"
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.
Available platform plugins are: linuxfb, minimal, offscreen, vnc.So shall I reinstall the Qt or add some plugins?
Thank you -
Start your application with the QT_DEBUG_PLUGINS environment variable set to 1 to see why the loading fails.
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@SGaist said in qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:
Start your application with the QT_DEBUG_PLUGINS environment variable set to 1 to see why the loading fails.
I've set the QT_DEBUG_PLUGINS environment variable in the .bashrc file and sourced it. See floor.134
But these is no error message while loading qtcreator.sugon@EC:~$ echo $QT_DEBUG_PLUGINS
1
sugon@EC:~$ -
@hskoglund said in qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:
Hi, perhaps you are launching Qt Creator by double clicking on it?
If so, instead try starting Qt Creator from the same Terminal window that has QT_DEBUG_PLUGINS set to 1.Thank you, but I always start qtcreator in terminal. It can be seen in floor.134
sugon@EC:~$ source ~/.bashrc
sugon@EC:~$ ~/Software/qtcreator8.0.1/bin/qtcreator
sugon@EC:~$ ~/QtProject/build-Test-Qt_6_3_1_in_PATH_Qt6_3_1-Debug/TestThere's no error message until I closed the software.
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@mywings19 said in qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:
There's no error message until I closed the software.
In that case when does the message you showed earlier:
qt.qpa.plugin: Could not find the Qt platform plugin "xcb" in "/home/sugon/Software/Qt6.3.1/plugins/platforms/" This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem. Available platform plugins are: linuxfb, minimal, offscreen, vnc.
appear? Not until after you close Creator? Interesting.....
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@JonB said in qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:
@mywings19 said in qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:
There's no error message until I closed the software.
In that case when does the message you showed earlier:
qt.qpa.plugin: Could not find the Qt platform plugin "xcb" in "/home/sugon/Software/Qt6.3.1/plugins/platforms/" This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem. Available platform plugins are: linuxfb, minimal, offscreen, vnc.
appear? Not until after you close Creator? Interesting.....
This 3 line message is showed when I build and run a test project.
I mean after I set QT_DEBUG_PLUGINS to 1, There's no extra error message except this 3 line when I start qtcreator or run project in terminal.Now, I've uninstall the Qt and qtcreator,then installing by online installer.
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Is that a custom Qt build ? Because from the looks of it, the plugin is indeed not there.
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In my case, I just upgrade PyQt5 to PyQt6 and that works.
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@trimixotun this worked!! Thank you so much!
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Hi,
I know this is an old post, but I have the same issue that comes up when I'm setting some path for the LD_Library_path.
for the context i'm creating a container that run an app with a gui using pyqt5, which works perfectly.
However, I also need to install matlab runtime and after I set up Matlab runtime environement path :
LD_LIBRARY_PATH=/opt/mscr/v912/runtime/glnxa64:/opt/mcr/v912/bin/glnxa64:/opt/mcr/v912/sys/os/glnxa64:/opt/mcr/v912/sys/opengl/lib/glnxa64
the gui stops working and I get the "qt.qpa.plugin ..." error message.
Any thoughts?
Thanks a lot -
@roux-benoit hi,
Check whether there's Qt libraries in your matlab installation.
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I hope someone on this forum can help me. I'm trying to use Howdy (https://github.com/boltgolt/howdy), but I get the error described by OP.
I only get the error when I usesu -
, however when I use plainsu
(without the-
) it works. So I think i somehow messed up the install when I forgot to add the-
... how can I fix this?the error:
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. ``
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@phil-lipp
https://forum.qt.io/post/763171 was just asked. -
I had too problems with this file.
It just depends from which shared file left you.
first at all set in the console :export QT_DEBUG_PLUGINS=1
This will show you in which part it fails, normally is in libqxcb.so,
example:
python main.pyqt.core.plugin.factoryloader: checking directory path "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms" ... qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-generic.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-generic.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "wayland" ] }, "archlevel": 1, "className": "QWaylandIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("wayland") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimal.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimal.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "minimal" ] }, "archlevel": 1, "className": "QMinimalIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("minimal") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqeglfs.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqeglfs.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "eglfs" ] }, "archlevel": 1, "className": "QEglFSIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("eglfs") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-egl.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqwayland-egl.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "wayland-egl" ] }, "archlevel": 1, "className": "QWaylandEglPlatformIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("wayland-egl") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqoffscreen.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqoffscreen.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "offscreen" ] }, "archlevel": 1, "className": "QOffscreenIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("offscreen") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqlinuxfb.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqlinuxfb.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "linuxfb" ] }, "archlevel": 1, "className": "QLinuxFbIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("linuxfb") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvnc.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvnc.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "vnc" ] }, "archlevel": 1, "className": "QVncIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("vnc") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvkkhrdisplay.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqvkkhrdisplay.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "vkkhrdisplay" ] }, "archlevel": 1, "className": "QVkKhrDisplayIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("vkkhrdisplay") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimalegl.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqminimalegl.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "minimalegl" ] }, "archlevel": 1, "className": "QMinimalEglIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("minimalegl") qt.core.plugin.factoryloader: looking at "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" qt.core.plugin.loader: Found metadata in lib /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so, metadata= { "IID": "org.qt-project.Qt.QPA.QPlatformIntegrationFactoryInterface.5.3", "MetaData": { "Keys": [ "xcb" ] }, "archlevel": 1, "className": "QXcbIntegrationPlugin", "debug": false, "version": 394496 } qt.core.plugin.factoryloader: Got keys from plugin meta data QList("xcb") qt.core.plugin.factoryloader: checking directory path "/usr/bin/platforms" ... qt.core.library: "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" cannot load: Cannot load library /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: (libxcb-cursor.so.0: cannot open shared object file: No such file or directory) qt.core.plugin.loader: QLibraryPrivate::loadPlugin failed on "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" : "Cannot load library /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: (libxcb-cursor.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. Available platform plugins are: wayland, minimal, eglfs, wayland-egl, offscreen, linuxfb, vnc, vkkhrdisplay, minimalegl, xcb. zsh: IOT instruction python main.py
And this error occurs when some of the shared libraries are not found.
In my case was the :
"/usr/bin/platforms" ...
qt.core.library: "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" cannot load: Cannot load library /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so:== =>(libxcb-cursor.so.0: cannot open shared object file: No such file or directory) <===
qt.core.plugin.loader: QLibraryPrivate::loadPlugin failed on "/home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so" : "Cannot load library /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: (libxcb-cursor.so.0: cannot open shared object file: No such file or directory)"
.
This is the shared library that lefts , it could that does not be the only one , so for see better which shared libraries are and which not use the next command :ldd : /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so
This must show you the next thing :
:: ldd: ./:: No such file or directory /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/libqxcb.so: linux-vdso.so.1 (0x00007fff8b5b6000) libQt6XcbQpa.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6XcbQpa.so.6 (0x00007febd8bec000) libxkbcommon-x11.so.0 => /lib/x86_64-linux-gnu/libxkbcommon-x11.so.0 (0x00007febd8bc3000) libxkbcommon.so.0 => /lib/x86_64-linux-gnu/libxkbcommon.so.0 (0x00007febd8b7d000) libxcb-cursor.so.0 => not found libxcb-icccm.so.4 => /lib/x86_64-linux-gnu/libxcb-icccm.so.4 (0x00007febd8b76000) libxcb-image.so.0 => /lib/x86_64-linux-gnu/libxcb-image.so.0 (0x00007febd8b6e000) libxcb-keysyms.so.1 => /lib/x86_64-linux-gnu/libxcb-keysyms.so.1 (0x00007febd8800000) libxcb-randr.so.0 => /lib/x86_64-linux-gnu/libxcb-randr.so.0 (0x00007febd8b5d000) libxcb-render-util.so.0 => /lib/x86_64-linux-gnu/libxcb-render-util.so.0 (0x00007febd8400000) libxcb-shm.so.0 => /lib/x86_64-linux-gnu/libxcb-shm.so.0 (0x00007febd8b58000) libxcb-sync.so.1 => /lib/x86_64-linux-gnu/libxcb-sync.so.1 (0x00007febd8b50000) libxcb-xfixes.so.0 => /lib/x86_64-linux-gnu/libxcb-xfixes.so.0 (0x00007febd8b45000) libxcb-render.so.0 => /lib/x86_64-linux-gnu/libxcb-render.so.0 (0x00007febd8b37000) libxcb-shape.so.0 => /lib/x86_64-linux-gnu/libxcb-shape.so.0 (0x00007febd8b32000) libxcb-xkb.so.1 => /lib/x86_64-linux-gnu/libxcb-xkb.so.1 (0x00007febd8b15000) libxcb.so.1 => /lib/x86_64-linux-gnu/libxcb.so.1 (0x00007febd8aeb000) libQt6OpenGL.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6OpenGL.so.6 (0x00007febd8a4a000) libQt6Gui.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6Gui.so.6 (0x00007febd7a00000) libGL.so.1 => /lib/x86_64-linux-gnu/libGL.so.1 (0x00007febd8779000) libQt6Core.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6Core.so.6 (0x00007febd7200000) libX11-xcb.so.1 => /lib/x86_64-linux-gnu/libX11-xcb.so.1 (0x00007febd8a43000) libX11.so.6 => /lib/x86_64-linux-gnu/libX11.so.6 (0x00007febd8637000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007febd8a3c000) libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007febd8a37000) libstdc++.so.6 => /lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007febd6e00000) libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007febd7921000) libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007febd8a17000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007febd701f000) libxcb-cursor.so.0 => not found libglib-2.0.so.0 => /lib/x86_64-linux-gnu/libglib-2.0.so.0 (0x00007febd6cbd000) libgthread-2.0.so.0 => /lib/x86_64-linux-gnu/libgthread-2.0.so.0 (0x00007febd8a10000) libxcb-util.so.1 => /lib/x86_64-linux-gnu/libxcb-util.so.1 (0x00007febd8a08000) libXau.so.6 => /lib/x86_64-linux-gnu/libXau.so.6 (0x00007febd8a03000) libXdmcp.so.6 => /lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007febd6a00000) libEGL.so.1 => /lib/x86_64-linux-gnu/libEGL.so.1 (0x00007febd861f000) libfontconfig.so.1 => /lib/x86_64-linux-gnu/libfontconfig.so.1 (0x00007febd78d6000) libQt6DBus.so.6 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libQt6DBus.so.6 (0x00007febd693b000) libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007febd83e1000) libfreetype.so.6 => /lib/x86_64-linux-gnu/libfreetype.so.6 (0x00007febd6870000) libGLdispatch.so.0 => /lib/x86_64-linux-gnu/libGLdispatch.so.0 (0x00007febd67b7000) libGLX.so.0 => /lib/x86_64-linux-gnu/libGLX.so.0 (0x00007febd78a2000) libicui18n.so.56 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libicui18n.so.56 (0x00007febd6200000) libicuuc.so.56 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libicuuc.so.56 (0x00007febd5e00000) libicudata.so.56 => /home/user/.local/lib/python3.11/site-packages/PySide6/Qt/plugins/platforms/../../lib/libicudata.so.56 (0x00007febd4400000) librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007febd8616000) /lib64/ld-linux-x86-64.so.2 (0x00007febd8ca7000) libpcre2-8.so.0 => /lib/x86_64-linux-gnu/libpcre2-8.so.0 (0x00007febd6c23000) libbsd.so.0 => /lib/x86_64-linux-gnu/libbsd.so.0 (0x00007febd83cb000) libexpat.so.1 => /lib/x86_64-linux-gnu/libexpat.so.1 (0x00007febd678c000) libdbus-1.so.3 => /lib/x86_64-linux-gnu/libdbus-1.so.3 (0x00007febd6736000) libpng16.so.16 => /lib/x86_64-linux-gnu/libpng16.so.16 (0x00007febd6700000) libbrotlidec.so.1 => /lib/x86_64-linux-gnu/libbrotlidec.so.1 (0x00007febd8607000) libmd.so.0 => /lib/x86_64-linux-gnu/libmd.so.0 (0x00007febd7895000) libsystemd.so.0 => /lib/x86_64-linux-gnu/libsystemd.so.0 (0x00007febd4331000) libbrotlicommon.so.1 => /lib/x86_64-linux-gnu/libbrotlicommon.so.1 (0x00007febd66dd000) libcap.so.2 => /lib/x86_64-linux-gnu/libcap.so.2 (0x00007febd6c17000) libgcrypt.so.20 => /lib/x86_64-linux-gnu/libgcrypt.so.20 (0x00007febd41ea000) liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007febd66ae000) libzstd.so.1 => /lib/x86_64-linux-gnu/libzstd.so.1 (0x00007febd412e000) liblz4.so.1 => /lib/x86_64-linux-gnu/liblz4.so.1 (0x00007febd61da000) libgpg-error.so.0 => /lib/x86_64-linux-gnu/libgpg-error.so.0 (0x00007febd4106000)
As you can see the shared library which is not , appears like not found
libxcb-cursor.so.0 => not found
Just thus easier to fix it , is using :
sudo apt install libxcb-cursor0
In your case could be another like: libxcb-randr0
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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: offscreen, wayland, vnc, minimalegl, xcb, wayland-egl, eglfs, linuxfb, vkkhrdisplay, minimal.
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
sudo apt-get install libxcb-xinerama0
++++++++++++++++++++++++++++++++++
sudo apt-get install -qq libglu1-mesa-dev libx11-xcb-dev '^libxcb*'