I wanted to create a small dialog that using buttons we can add some numbers.
First I designed a form by Qt Designer using Dialog Without Buttons template like this:

1.jpg

Then I wrote a calculator.h file like this:


Qt Code: 
  1. #ifndef CALCULATOR_H
  2. #define CALCULATOR_H
  3.  
  4. #include<QDialog>
  5. #include "ui_Calculator.h"
  6.  
  7. class Calculator : public QDialog, public Ui::Calculator
  8. {
  9.     Q_OBJECT
  10.  
  11. public:
  12.     Calculator(QWidget* parent = 0);
  13.  
  14. private slots:
  15.    void myslot();
  16. };
  17.  
  18. #endif // CALCULATOR_H
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Then, a calculator.cpp this way:


Qt Code: 
  1. #include <QtWidgets>
  2. #include "calculator.h"
  3.  
  4. Calculator::Calculator(QWidget *parent)
  5.     :QDialog(parent)
  6. {
  7.     setupUi(this);
  8.  
  9.     connect(oneButton,SIGNAL(clicked(bool)), lineEdit, SLOT(myslot()));
  10. }
  11.  
  12. void Calculator::myslot(){
  13.     lineEdit -> setText("1");
  14. }
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And finally the main.cpp this way:

Qt Code: 
  1. #include <QApplication>
  2. #include <QDialog>
  3.  
  4. #include "ui_Calculator.h"
  5.  
  6. int main(int argc, char* argv[])
  7. {
  8.     QApplication app(argc, argv);
  9.  
  10.     Ui::Calculator ui;
  11.     QDialog* dialog = new QDialog;
  12.     ui.setupUi(dialog);
  13.     dialog -> show();
  14.  
  15.     return app.exec();
  16. }
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Now the code runs without any error but not as expected! That is when I click on '1' button nothing will be printed out onto the lineEdit.
Why please and how to solve it?