how to build simple qt application using yocto? - qt

Question

I have yocto dev environment setup, in which I can bitbake and run a simple c++ application in the target. Now I want to try with simple Qt application. When I execute bitbake-layers show-layers it shows meta-qt5 in the list...
meta-qt5
/home/prc1cob/repo/out/salt/kawa/../../..//os/external/meta-qt5 7
meta-oe
/home/prc1cob/repo/out/salt/kawa/../../../build/yocto/meta-openembedded/meta-oe
6
With this, I assume qt5 is already present in my yocto build.
How to write .bb file to build a simple HelloWorld qt application as below...
#include <QCoreApplication>
#include <QDebug>
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
qDebug() << "Hello World";
return a.exec();
}
Thankyou!!

Answer 1

Yocto provides a great class qmake5 to compile QT projects based on QMake.
In order to use it create a .pro file for the project:
qtexample.pro
QT += core
SOURCES += qtexample.cpp
qtexample.cpp
#include <QCoreApplication>
#include <QDebug>
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
qDebug() << "Hello World";
return a.exec();
}
Now, in your layer, you can add a simple recipe that compiles that project.
For example: meta-custom/recipes-project/qtexample
In qtexample folder create files folder and copy qtexample.pro and qtexample.cpp in it.
In qtexample folder directly create qtexample_0.1.bb recipe:
SUMMARY = "QT Example Recipe"
LICENSE = "CLOSED"
SRC_URI = "file://qtexample.pro \
file://qtexample.cpp"
DEPENDS += "qtbase"
RDEPENDS_${PN} += "qtwayland"
S = "${WORKDIR}"
inherit qmake5
You can change the version ofcourse (0.1).
The layout should look like this:
meta-custom/
├── recipes-project/
├── qtexample_0.1.bb
└── files/
├── qtexample.pro
└── qtexample.cpp
Then, bitbake qtexample should work and create a qtexample binary that you can find in ${WORKDIR}