[solved] experimenting nzmqt hello world example

SherifOmran

hello
i installed zmq on mac using brew install zmq
followed by downloading nzmqt from git hub, i tried to create a new project with the following content, where i added the pri file given in github

QT -= gui
QT       += core


CONFIG += c++11 console
CONFIG -= app_bundle


TARGET = nzmqt_app
VERSION = 3.2.1
#DESTDIR = $$_PRO_FILE_PWD_/../bin

TEMPLATE = app


# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
        main.cpp



macx: LIBS += -L$$PWD/../../../../../usr/local/Cellar/zeromq/4.3.2/lib/ -lzmq

INCLUDEPATH += $$PWD/../../../../../usr/local/Cellar/zeromq/4.3.2/include
DEPENDPATH += $$PWD/../../../../../usr/local/Cellar/zeromq/4.3.2/include



include(../../Downloads/nzmqt-master/nzmqt.pri)

HEADERS +=

I made a simple project with the following content

#include <QCoreApplication>
#include "NzmqtApp.hpp"
#include <QtDebug>
QCoreApplication* b;

nzmqt::samples::SampleBase* commandImpl = nullptr ;

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    b=&a;


    return a.exec();
}

void run()
{

    nzmqt::ZMQContext* context= nzmqt::createDefaultContext(b);
    context->start();

    QString address = "127.0.0.1";
    QString topic = "abc";
    commandImpl = new nzmqt::samples::pubsub::Publisher(*context, address, topic,b);


}

The project has compile failure due to line

```

commandImpl = new nzmqt::samples::pubsub::Publisher(*context, address, topic,b);

I get 
symbols not found for archiecture x86_64, linker command failed with exit code 1

Undefined symbols for architecture x86_64:
"vtable for nzmqt::samples::SampleBase", referenced from:
nzmqt::samples::SampleBase::SampleBase(QObject*) in main.o
NOTE: a missing vtable usually means the first non-inline virtual member function has no definition.
"vtable for nzmqt::samples::pubsub::Publisher", referenced from:
nzmqt::samples::pubsub::Publisher::Publisher(nzmqt::ZMQContext&, QString const&, QString const&, QObject*) in main.o
NOTE: a missing vtable usually means the first non-inline virtual member function has no definition.
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [nzmqt_app] Error 1
21:55:51: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project testnmqt (kit: Desktop Qt 5.12.1 CLang)
When executing step "Make"
21:55:51: Elapsed time: 00:02.



if i comment it out, it compiles fine. I am still new to nzmqt and still dont know how to use it.

any help is appreciated.

SherifOmran

I corrected the code in the main.cpp to the following, now it compiles, but when i run a second instance as a subscriber, it does not receive this publisher ..
what is missing?

#include <QCoreApplication>
#include <nzmqt/nzmqt.hpp>
#include <QtDebug>
#include <nzmqt/SampleBase.hpp>
#include <nzmqt/Subscriber.hpp>
#include <nzmqt/Publisher.hpp>


QCoreApplication* b;


int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);
    b=&a;
    nzmqt::samples::SampleBase* commandImpl = nullptr ;

    nzmqt::ZMQContext* context= nzmqt::createDefaultContext(b);
    context->start();

    QString address = "tcp://127.0.0.1:1234";
    QString topic = "ping";

    commandImpl = new nzmqt::samples::pubsub::Publisher(*context, address, topic,b);



    return a.exec();
}

void run()
{



}

SherifOmran

this should work now

```

commandImpl->start();