qt simple tcp communication with ui projects - qt

Question

I want to create a simple Tcp Communication project but I get some problems and I dont know how to solve that problem. When I try to find solution all people tell add this code (QT += network)on .pro file but in ui projects I dont have any pro file so I dont know the find the solution.
//commu.h
#ifndef COMMU_H
#define COMMU_H
#include <QtWidgets/QMainWindow>
#include "ui_commu.h"
#include <QtNetwork/QTcpSocket>
#include <QObject>
#include <QString>
class commu : public QMainWindow
{
Q_OBJECT
public:
commu(QWidget *parent = 0);
~commu();
void start(QString address, quint16 port);
private:
Ui::commuClass ui;
QTcpSocket client;
public slots:
void startTransfer();
};
#endif // COMMU_H
//commu.cpp
#include "commu.h"
#include <QtNetwork/QHostAddress>
commu::commu(QWidget *parent)
: QMainWindow(parent)
{
ui.setupUi(this);
connect(&client, SIGNAL(connected()),this,SLOT(startTransfer()));
}
commu::~commu()
{
client.close();
}
void commu::start(QString address, quint16 port)
{
QHostAddress addr(address);
client.connectToHost(addr, port);
}
void commu::startTransfer()
{
client.write("Hello, world", 13);
}
//main.cpp
#include "commu.h"
#include <QtWidgets/QApplication>
#include <QtCore>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
commu w;
w.show();
return a.exec();
commu client;
client.start("127.0.0.1", 8888);
}
I get the errors:
1>commu.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: virtual __thiscall QTcpSocket::~QTcpSocket(void)" (__imp_??1QTcpSocket##UAE#XZ) referenced in function "public: virtual __thiscall commu::~commu(void)" (??1commu##UAE#XZ)
1>commu.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall QTcpSocket::QTcpSocket(class QObject *)" (__imp_??0QTcpSocket##QAE#PAVQObject###Z) referenced in function "public: __thiscall commu::commu(class QWidget *)" (??0commu##QAE#PAVQWidget###Z)
1>commu.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall QHostAddress::~QHostAddress(void)" (__imp_??1QHostAddress##QAE#XZ) referenced in function "public: void __thiscall commu::start(class QString,unsigned short)" (?start#commu##QAEXVQString##G#Z)
1>commu.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __thiscall QHostAddress::QHostAddress(class QString const &)" (__imp_??0QHostAddress##QAE#ABVQString###Z) referenced in function "public: void __thiscall commu::start(class QString,unsigned short)" (?start#commu##QAEXVQString##G#Z)
1>c:\users\sel\documents\visual studio 2010\Projects\commu\Win32\Debug\\commu.exe : fatal error LNK1120: 4 unresolved externals

Answer 1

You need to enable modules you're using in Qt Project Settings. More info you can find in Qt docs: Qt Visual Studio Add-in
You also shouldn't use includes like
#include <QtWidgets/QMainWindow>
you should always include only class file without path like
#include <QMainWindow>
Same goes for all modules, so skip QtNetwork etc after you enable modules for your project.