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only one QPushButton with QWidget works
Yes I try to run it remotely on a raspberry.
Now I have installed the kit for the host PC. Yes it works perfect on the host.
What can I do to make it working on a remote raspberry? I use /usr/bin/gdb-multiarch for debugging remotely on the raspberry. Is this ok
Do you mean that your application is working fine on your desktop and still not on your target ?
if the target is the linux host (ubuntu desktop) the application works fine.
If the target is the raspberry it does not work.
What about this info:
Could not load shared library symbols for 3 libraries, e.g. /usr/local/qt5pi/lib/libQt5Widgets.so.5.
Is there something missing?
Maybe somebody knows more about this problem.
What do you get if you call ldd on that file ?
@SGaist , where must I run ldd?
On the linux host PC or on the raspberry?
I will check it tomorrow
Sorry, I made a mistake
What do you mean with that ?
yesterday I had some trouble with my computer network and I couldn't write a post correcttly.
Here the output of lcc:
Do yoe need the output also when I run lcc on the on the Linux host?
Looks good. What is the exact error message you're getting when starting your application ?
there are no errors when I run the application. Only warnings during startup as I wrote eight days ago.
Now I install everything new because I have some big troubles with the network running a virtual machine (=Hyper-V). I install it now on oracles virtual box.
I will see what happens after this.
Now I have an other problem after a new installation:
It seems to be a configuration failure:
When I start the application I get a problem.
What means this? does it miss an egl module?
Process /opt/TestWidget/bin/TestWidget created; pid = 2877 qt.qpa.egldeviceintegration: Failed to load EGL device integration "eglfs_brcm" EGL library doesn't support Emulator extensions
and a window appears
I find no real help in the internet.
I use a MPI3508 LCD HDMI display on my raspberry3.
Maybe my current configuration cannot handle it.
Please has somebody an answer?
Do you mean that you have that error in a virtual machine ?
no I think something went wrong during the installation.
What mmeans this:
Failed to load EGL device integration "eglfs_brcm"
It's getting a bit fuzzy here. You seem to have issues both with your desktop machine and RaspberryPi.
Can you do a small summary of what is going on and where exactly ?
@SGaist , hello to all;
I'm sorry for the delay, but I made some investigation.
It seems to have just a little problem:
When I start the application local on the terminal then I first have to write
Then it works with a warning
libEGL warning: DRI2: failed to authenticate
Is there a way to add this command
automaticially before I run the application?
@k-str You can write a simple shell script which first sets the env variable and then calls your app and then use this script to start the app.
thanks for your answer!
Yes I know there was somthing like this but I have no Idea how such a script looks.
Where can I find an example? It should wor also for debugging
Two lines in the script:
export DISPLAY=:0 full-path-or-plain-name-of-your-executable
If you need it for debugging too, change second line to:
Assuming your mobile is like Linux (I know nothing about mobiles), if you go
chmod +x the-script
the-scriptis ready to execute.
Alternatively, and better if it works:
I do not know when your program needs that
DISPLAYenvironment variable set, how early on after start up. If it is literally as soon as as it loads then you will have to set the environment variable before invocation. But if it's not, say, until you first try to create the UI, before that (before creating the
QApplication) you could use Qt's
qputenv()to set that environment variable, e.g. perhaps if it is not already set to something so user can set
DISPLAYif needed but your code defaults it to
:0it it is not defined. Doing it this way, if possible, would get rid of the need to have a script wrapper.
thanks for your answer,
Is it also possible to start a script where you can pass the full path application?
Maybe a script which gets the application in a environment variable or so. E.g ??full-path-of-appl??* is the environment variable:
export DISPLAY=:0 gdbserver ??*full-path-of-appl*??
this means I have to start the script MyGDB by Qt-creator
Don't follow your question. In a script you can do whatever you could do from the command-line. If you mean: can a script access environment variables, or can a script examine and pass on arguments passed to it, the answer to both is yes.
You need to look at the documentation of whatever shell you are using for its scripting syntax. If you're Linux the standard one these days is
bash, I don't know if that applies to whatever mobile. In your question I wonder if you're asking if you can pass an argument to the script on the command line and then pass it on to your
gdbserver? In which case in
If it's in an envivironment variable:
this looks very good. I will try it tomorrow.
Thanks a lot!
Hi @JonB ,
thanks for your tip but I cannot find a way how to do this.
Is there a way to execute a program by Qt-Creator by running a bash-script on the target machine (=raspberry)?
It should look like :
#!/bin/bash export DISPLAY=:0 ??run or debug** <*application*>??
Maybe this is a new topic?
JonB last edited by
I don't know because I don't use Qt Creator! You should look at wherever it documents its command line arguments, maybe you go
Having said that, I would advise you again to consider what I have suggested about not having to use a separate script file and instead making your code use
qputenv()to set the
DISPLAYenvironment variable very early, if it's not already set (use
qgetetnv()for that), if you can make that work. Your life will be easier for both development and release if you do not have a separate wrapper.
@k-str There is no need for this script work around when running in QtCreator: go to Projects/Build & Run/Run and add the DISPLAY variable there in "Run Environment".
thanks, this sounds quiet easy! But I cannot find the point "Run Environment" where I can insert DISPLAY=:0.
I don't use Qt Creator, but I think you need to scroll down on that dialog on the right, did you not try that?
@k-str Scroll down...
@jsulm, hi to all,
I'm sorry, but I think I made some failures.
I checked everything and I think the problem is the LCD hardware.
I use one
- QUIMAT 3.5"
- HDMI Display-B
- 480x320 Dots V1.2
- type MPI3508
- pen interface SPI
Maybe this cannot handle EGL mode.
Which plugin should I use for this LCD display?
I configered xcb but this is not ok. See below.
Now I installed Qt completely new using this instructions:
and also some modifications from here;
The configuration command is:
./configure -release -no-eglfs -qt-xcb -xcb -device linux-rasp-pi3-g++ -device-option CROSS_COMPILE=~/raspi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin/arm-linux-gnueabihf- -sysroot ~/raspi/sysroot -opensource -confirm-license -make libs -prefix /usr/local/qt5pi -extprefix ~/raspi/qt5pi -hostprefix ~/raspi/qt5 -v -no-use-gold-linker
But I still get errors
qt.qpa.plugin: Could not find the Qt platform plugin "eglfs" in "" 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, xcb.
Are there instructions how to configure xcb or linuxfb or one of the above mentioned plugins
I give up to install Qt Creator for remote development. It's like "Sisyphean task".
Now I installed Qt on my Raspberry and here I try to do my work.
I use the RemoteDesktop.
It seems it works for me.
Thanks a lot to all helpers.