Want to add pushbutton to setTimer and setText - c++

Question

I am newbie in GUI design. Here, in sending and receiving messages (float, integer values) using DDS (OpenSplice) I am trying to add a pushButton to my already existing labels(displaying some float values as shown below), so that after a clicking on the pushButton, I should be able to see data in my label.
I tried adding a push button with the help of Qt Network sender Example. Now I get the error undefined reference to 'MainWindow::on_pushButton_clicked() in the file moc_mainwindow.cpp while building the project.
fastsender.cpp
FastSender::FastSender(QLabel *x, QObject *parent) : QObject(parent)
{
wSend = x;
dataTimer = new QTimer(this);
emergency = new QPushButton(tr("Emergency"));
buttonBox = new QDialogButtonBox;
buttonBox->addButton(emergency,QDialogButtonBox::ActionRole);
connect(emergency, SIGNAL(clicked()), this, SLOT(startsending()));
connect(dataTimer, SIGNAL(timeout()), this, SLOT(walk()));
QVBoxLayout *mainLayout = new QVBoxLayout;
mainLayout->addWidget(buttonBox);
}
void FastSender::startsending()
{
emergency->setEnabled(false);
dataTimer->start(100); // Interval 0 means to refresh as fast as possible
}
int FastSender::walk()
{
msg->value= i+0.1;
snprintf (buf, MAX_MSG_LEN, "Message no. %d", i);
cout << "Writing message: \"" << msg->value << "\"" << endl;
status = talker->write(*msg, userHandle);
QString s= QString::number(msg->value, 'f',8);
wSend->setText(s);
}
fastsender.h
class FastSender : public QObject
{
Q_OBJECT
public:
explicit FastSender(QObject *parent = 0);
FastSender(QLabel *x, QObject *parent = 0);
~FastSender();
signals:
private:
QTimer* dataTimer;
QLabel *wSend;
DDS::DomainParticipantFactory_var dpf;
DDS::DomainParticipant_var parentDP;
DDS::Topic_var signalTopic;
DDS::DataReader_var parentReader;
DDS::DataWriter_var parentWriter;
fw::signalSeq_var msgSeq;
char * signalTypeName;
fw::signalDataWriter_var talker;
fw::signal *msg;
DDS::InstanceHandle_t userHandle;
DDS::Publisher_var fwPublisher;
int alpa;
QPushButton *emergency;
QDialogButtonBox *buttonBox;
public slots:
int walk();
int hello();
void startsending();
};
mainwindow.cpp
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
fwdds = new FastWanDDS(ui->label);//receiving values are displayed in label
fwdds1 = new FastSender(ui->label_2);//Sending values are displayed in label_2
}
mainwindow.h
Ui::MainWindow *ui;
QTimer* timer;
int counter;
FastWanDDS *fwdds;
FastSender *fwdds1;
Any Help Appreciated.
Note: Only snippets of the code presented

Answer 1

I got it to work this way. Does this work for you?
mainwindow.cpp
#include "mainwindow.h"
#include "fastsender.h"
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
{
QLabel* label = new QLabel("unchanged");
FastSender* fs = new FastSender(label);
setCentralWidget(fs);
}
MainWindow::~MainWindow()
{
}
fastsender.h
#ifndef FASTSENDER_H
#define FASTSENDER_H
#include <QLabel>
#include <QTimer>
#include <QPushButton>
#include <QDialogButtonBox>
#include <QHBoxLayout>
class FastSender : public QWidget
{
Q_OBJECT
public:
FastSender(QLabel* label, QWidget* parent = 0)
: QWidget(parent)
, _label(label)
, _timer(new QTimer)
, _emergency(new QPushButton(tr("Emergency")))
, _bbox(new QDialogButtonBox)
{
_bbox->addButton(_emergency, QDialogButtonBox::ActionRole);
QHBoxLayout* layout = new QHBoxLayout;
layout->addWidget(_label);
layout->addWidget(_bbox);
setLayout(layout);
connect(_emergency, SIGNAL(clicked(bool)), this, SLOT(startsending()));
connect(_timer, SIGNAL(timeout()), this, SLOT(walk()));
}
public slots:
void startsending()
{
_emergency->setEnabled(false);
_timer->start(100);
}
int walk()
{
_label->setText("changed");
_emergency->setEnabled(true);
}
private:
QLabel* _label;
QTimer* _timer;
QPushButton* _emergency;
QDialogButtonBox* _bbox;
};
#endif // FASTSENDER_H