SLOT DOUBT

R P Shah

Hello,
I am new in QT.
Help me to solve my doubt.
I don't get it why slot function is not called.

Main.CPP file
-------------------

#include <QApplication>
#include "pushbutton.h"

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    pushbutton1 push;
    push.show();
//    push.window.show();
    return app.exec();
}

pushbutton.h file
-------------------------
#ifndef PUSHBUTTON_H
#define PUSHBUTTON_H

#include <QWidget>
#include <QLabel>
#include <QPushButton>
#include <QLineEdit>
#include <QMessageBox>
#include <QMainWindow>

class pushbutton1 : public QWidget
{

public:
    explicit pushbutton1();
    ~pushbutton1();
//    QWidget window;
    QMessageBox box;

private slots:
    void popup();

private:

QLabel *Label;
QPushButton *ok;
QPushButton *cancel;
QLineEdit line;

};

#endif // PUSHBUTTON_H

pubutton.cpp file
-------------------------
#include <iostream>
#include <QDebug>
#include "pushbutton.h"
#include "main.cpp"

void pushbutton1 :: popup()
{
    qDebug() << "Hello How are you?";
//    cout << "Hello" << endl;
//    QMessageBox::information(this, "Line MSG", line.text());
    box.setText(line.text());
    box.show();
}

pushbutton1::pushbutton1()
{
    //class Rushin r1;

    Label = new QLabel("Enter Text:",this);
    Label->resize(90,30);
    Label->setStyleSheet("background-color:white;border-style: outset;\
                        border-width: 1px; border-color: black;");

//    line = new QLine("0",&window);
    //line("",&window);
    line.setParent(this);
    line.resize(100,30);
    line.move(95,0);
    line.setStyleSheet("border-style: outset;\
                        border-width: 1px; border-color: black;");

    ok = new QPushButton("OK",this);
    ok->move(50,35);
    ok->resize(50,30);

    cancel = new QPushButton("Cancel",this);
    cancel->move(110,35);
    cancel->resize(50,30);

//    box.setParent(&window);
    box.resize(100,100);
    box.setWindowTitle("Display");
    box.setText(line.text());

    connect(cancel, SIGNAL(clicked()), this, SLOT(close()));
    connect(&line, SIGNAL(returnPressed()), SLOT(popup()));
    connect(ok, SIGNAL(clicked()), SLOT(popup()));

//    window.show();

}

pushbutton1::~pushbutton1()
{

}```
//your code here

SGaist

Hi and welcome to devnet,

You're missing the Q_OBJECT macro in your class declaration.

On a side note, it's Qt, QT stands for Apple QuickTime which you might also be using ;)

mrjj

hi
You need Q_OBJECT in your class for signals to work
like
class pushbutton1 : public QWidget
{
Q_OBJECT

After adding this, please run qmake. Normal compile is not enough.

Also as trick.
use
qDebug() to see if connect is true. so u know if it is ok

qDebug() << "result: " << connect(ok, SIGNAL(clicked()), SLOT(popup()));

(#include <QDebug>)

R P Shah

This post is deleted!

R P Shah

@mrjj :
Hello,
As per your explanation, I have changed in my code but now It shows compilation error
like below.
undefined reference to 'vtable for pushbutton1' and Id returned 1 exit status.
Please solve it.

SGaist

Do as @mrjj suggested: re-run qmake before building or do a full rebuild.