Qt platform plugin "xcb"

snapcraft
1

When I try to start the application, I see an error

This application failed to start because it could not find or load the Qt platform plugin "xcb".
Available platform plugins are: linuxfb, minimal, offscreen, xcb.

As I understand it is connected with plugins QT_QPA_PLATFORM_PLUGIN_PATH
If I’m wrong, correct me.
These plugins are with the QT.
How do correctly specify the settings for them where they are located?
Thx

2

Hey blinct
You need desktop helper to simplify Qt-based apps snapping.
What you need to do
1) add after: [desktop-qt5] in your part
2) run your apps with desktop-launch utility

Replace the desktop-qt5 with desktop-qt4 if it’s a qt4-based app.
You probably need to run the following command to update the remote parts upfront.

$ snapcraft update

Here is a trivial example you can refer to

Thanks.

2 Likes
3

It’s my snapcraft.yaml

name: bsp095project
version: "1.0"
summary: timer
description: |
    Application for medical testing
confinement: devmode
grade: devel
architectures: [amd64]

apps:
    BSP095launcherCoreSimulation:
        command: bin/run.sh $SNAP/bin/start_CORE_simulation.sh
        plugs: ['home', 'x11', 'opengl', 'gsettings', 'raw-usb', 'serial-port', 'network']
#        environment:
#            LD_LIBRARY_PATH: $SNAP/usr/BTL/
#            LD_LIBRARY_PATH: $SNAP/usr/BTL/Simulation
#            LD_LIBRARY_PATH: $SNAP/QT/5.5/gcc_64/lib
    BSP095launcherCore:
        command: bin/run.sh $SNAP/bin/start_CORE_hardware.sh
        plugs: ['home', 'x11', 'opengl', 'gsettings', 'raw-usb', 'serial-port', 'network']
#        environment:
#            LD_LIBRARY_PATH: $SNAP/usr/BTL/
#            LD_LIBRARY_PATH: $SNAP/usr/BTL/CommProtV200
#            LD_LIBRARY_PATH: $SNAP/QT/5.5/gcc_64/lib
    BSP095launcherCoreDaemon:
        command: bin/run.sh $SNAP/bin/start_CORE_hardware.sh --start
        daemon: simple
        stop-command: bin/run.sh $SNAP/bin/start_CORE_hardware.sh --stop
        stop-timeout: 10s
        plugs: ['home', 'x11', 'opengl', 'gsettings', 'raw-usb', 'serial-port', 'network']
#        environment:
#            LD_LIBRARY_PATH: $SNAP/usr/BTL
#            LD_LIBRARY_PATH: $SNAP/QT/5.5/gcc_64/lib
    BSP095launcherGui:
        command: bin/run.sh $SNAP/bin/start_GUI.sh
        plugs: ['home', 'x11', 'opengl', 'gsettings', 'pulseaudio', 'network']
#        environment:
#            LD_LIBRARY_PATH: $SNAP/usr/BTL
#            LD_LIBRARY_PATH: $SNAP/QT
    BSP095launcherMaintenance:
        command: bin/run.sh $SNAP/bin/start_maintenance_hardware.sh
        plugs: ['home', 'x11', 'opengl', 'gsettings', 'pulseaudio', 'network']
#        environment:
#            LD_LIBRARY_PATH: $SNAP/usr/BTL
#            LD_LIBRARY_PATH: $SNAP/QT

parts:
    files:
        plugin: dump
        source: scripts
        after: [integration]

    integration:
        plugin: nil
        stage-packages:
            - libc-bin
            - libclutter-1.0-0
            - libxkbcommon0
            - ttf-ubuntu-font-family
            - dmz-cursor-theme
            - libglib2.0-0
            - light-themes
            - shared-mime-info
            - libqt5gui5
            - libgdk-pixbuf2.0-0
            - libqt5svg5
            - libqt5quick5
            - libsqlite0
            - libqt5sql5
            - libqt5sql5-sqlite
            - libsqlite3-0
            - appmenu-qt5
            - libqt5qml5
            - libqt5quickwidgets5
            - qml-module-qtquick-controls
            - qml-module-qtqml-models2
            - qmlscene
            - qml-module-qt-labs-folderlistmodel
            - qml-module-qtquick-xmllistmodel
        after: [desktop/qt5]

I’m using the commercial version QT 5.5

4

You need to use the desktop-launch wrapper script to launch your app, as shown in @gary-wzl’s example. This is what takes care of setting the environment variables for you.

5

run.sh it’s renamed desktop-launch

6

So your run.sh is identical to the script that the cloud part would generate for you? Because the desktop-launch from the part definitely sets the relevant environment variables:

7

In this file I have such lines.
And yes, you are right, this is the generated file.