Unknown module(s) in QT: quickcontrols2

[SGaist]

What distribution are you using ?

[DarkPatate]

@SGaist As I said, I use Raspbian :

PRETTY_NAME="Raspbian GNU/Linux 9 (stretch)"
NAME="Raspbian GNU/Linux"
VERSION_ID="9"
VERSION="9 (stretch)"
ID=raspbian
ID_LIKE=debian
HOME_URL="http://www.raspbian.org/"
SUPPORT_URL="http://www.raspbian.org/RaspbianForums"
BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs"

At less you want more informations?

[SGaist]

Did you check whether you have this library somewhere on your OS ?

[DarkPatate]

@SGaist I tried this function:

ldconfig -p | grep libgles2-mesa-dev

I have no output, so I suppose the lib is not installed? So why apt-get told me it is already installed?

[SGaist]

You are mixing the name of the package and the name of the library. Use grep -i gles.

[DarkPatate]

@SGaist said in Unknown module(s) in QT: quickcontrols2:

grep -i gles

I got this result:

pi@raspberrypi:/ $ ldconfig -p | grep -i gles
	libbrcmGLESv2.so (libc6,hard-float) => /opt/vc/lib/libbrcmGLESv2.so
	libGLESv1_CM.so.1 (libc6,hard-float) => /usr/lib/arm-linux-gnueabihf/libGLESv1_CM.so.1

Both folder don't exist.

[SGaist]

IIRC, the quick workaround would to create a symbolic link named libGLESv2.so to your libbrcmGLESv2.so

[DarkPatate]

@SGaist
I never did that before.
So I tried that :

sudo ln -s /opt/vc/lib/libbrcmGLESv2.so /opt/vc/lib/libGLESv2.so

But now the compilation failed:

pi@raspberrypi:~/Documents/urecran/appliUR $ make
g++ -Wl,-O1 -Wl,-rpath-link,/usr/lib/arm-linux-gnueabihf -o appliUR main.o strategiesmodel.o communication.o qrc_qml.o moc_strategiesmodel.o moc_communication.o   -lQt5QuickControls2 -lQt5Quick -lQt5Gui -lQt5Qml -lQt5Network -lQt5Core -lGLESv2 -lpthread 
/usr/bin/ld: cannot find -lGLESv2
collect2: error: ld returned 1 exit status
Makefile:143: recipe for target 'appliUR' failed
make: *** [appliUR] Error 1

It was the right command?

[SGaist]

Because the linker won't search for libraries in /opt/vc/lib/. Add it to your .pro file with a line like LIBS += -L/opt/vc/lib/

[DarkPatate]

@SGaist
Visibly another component need the lib and doesn't find the symbolic link. Sorry to be so nooby.

pi@raspberrypi:~/Documents/urecran/appliUR $ make
g++ -Wl,-O1 -Wl,-rpath-link,/usr/lib/arm-linux-gnueabihf -o appliUR main.o strategiesmodel.o communication.o qrc_qml.o moc_strategiesmodel.o moc_communication.o   -L/opt/vc/lib/ -lQt5QuickControls2 -lQt5Quick -lQt5Gui -lQt5Qml -lQt5Network -lQt5Core -lGLESv2 -lpthread 
/usr/bin/ld: warning: libGLESv2.so.2, needed by /usr/lib/gcc/arm-linux-gnueabihf/6/../../../arm-linux-gnueabihf/libQt5Quick.so, not found (try using -rpath or -rpath-link)

[DarkPatate]

I am stupid, it's just a warning. The application compiled.
I just have a problem when I want to execute the program. The symbolic link doesn't work:

./appliUR: error while loading shared libraries: libGLESv2.so: cannot open shared object file: No such file or directory

[sierdzio]

You need to enable the vc4 gpu driver in raspi-config. I think it is listed under experimental section.

[DarkPatate]

@sierdzio
I was in :

7 Advanced options > A7 GL Driver > G1 GL (Full KMS)

(I din't find reference to VC4 GPU Driver in my raspi-config)

I don't now if it's that? But it didn't work, even after reboot.

[SGaist]

Modify LD_LIBRARY_PATH so that it also point to that folder.

[sierdzio]

@DarkPatate said in Unknown module(s) in QT: quickcontrols2:

I don't now if it's that? But it didn't work, even after reboot.

Looks like it. Shame it didn't work. Try the other options maybe, but they are less likely to work.

[DarkPatate]

@SGaist now all the librairy are found. But there is a missing plugin:

pi@raspberrypi:~/Documents/appliUR $ ./appliUR 
This application failed to start because it could not find or load the Qt platform plugin "eglfs"
in "".

Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, xcb.

Reinstalling the application may fix this problem.
Aborted

So I tried to create a sym link to the EGL lib too:

sudo ln -s /opt/vc/lib/libbrcmEGL.so /opt/vc/lib/libEGL.so

But it didn't work. It's almost working!

@sierdzio I tried all options, without success.

[sierdzio]

Eglfs platform plugin is a Qt plugin, located in <qt dir>/plugins/platforms.

Most probably your Qt was compiled for XCB (X11) only. Try running your app with -platform xcb argument (but expect low performance from this plugin...).

[DarkPatate]

@sierdzio said in Unknown module(s) in QT: quickcontrols2:

-platform xcb

I got the same pb with xcb. I tried also linuxfb and minimal, without success :/

[sierdzio]

I see. Well, that answer won't make you happy, perhaps, but: try following the "RPI eglfs" (Google it) guide and cross compile Qt yourself.

If definitely works, I've used Qt, with Qt Quick, many times. There are issues with the drivers, sure. But in general it works.

[DarkPatate]

@sierdzio sorry for the very late reply, I was so busy. I tried this solution long time ago but I failed. I will try again and let you know :)