Connection between Qpushbutton with line Edit widgets

cholokid

My problem is that, i want to create a simple calculator as a desktop application,
so , i have already create a Qpushbuttons with label 1,2,3,4,5 and so on . So if user click the button as signal, so the line Edit widget receive the corresponding number that is clicked(display that number).
please help me!!!

SGaist

Hi and welcome to devnet,

There's an "example":http://qt-project.org/doc/qt-4.8/widgets-calculator.html in Qt's documentation doing exactly that

BlackStar

be the class CalculatorUi
@class CalculatorUi : public Widget
{
Q_OBJECT
QPushButton* oneButton;
QLineEdit* displayScreen;
public :
CalculatorUi(QWidget* parent) : QWidget(parent),oneButton(new QPushButton("1")),displayScreen(new QLineEdit())
{
QVBoxLayout* layout (new QVBoxLayout);
layout->addWidget(displayScreen);
layout->addWidget(oneButton);

     connect(oneButton,SIGNAL(clicked()),this,SLOT(concatOne()));
 }

private slots :
  void concatOne()
   {
      displayScreen->setText(displayScreen->text() + "1");
    }

};@

This is just an example of how you can do it, hope it helped you,
we have a button wich is done for 1, and the display screen wich is of class QLineEdit, i created a private slot called concatOne and i connected it to the signal clicked of the button, so when you click on this button it append "1" to the value that you have into the screen !

cholokid

the first file, mainwindow.h

@#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
class MainWindow;
}@

@class MainWindow : public QMainWindow
{
Q_OBJECT

public:@
@ explicit MainWindow(QWidget *parent = 0);
~MainWindow();

private:
Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H@

second file, main.cpp
@
#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.show();@
@
return a.exec();
}@

third file, mainwindow.cpp

@#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);@

@
}

MainWindow::~MainWindow()
{
delete ui;@
@}
@

fourth file, mainwindiw.ui
this file , i have inserted the qpushbutton and line Edit widget, by draging.(graphically), so need to connenct the qpushbutton with line Edit, means that, if i clicked the button , line Edit show, the number to corresponding button, , i want to create a simple calculator. i am a beginer in qt programming.

JvdGlind

Assuming your QLineEdit is called 'lineEdit' and your QPushButton is called 'pushButton', adding the following to MainWindow will get you started:

@void MainWindow::on_pushButton_clicked()
{
ui->lineEdit->clear();
ui->lineEdit->insert(QString('1'));
}
@