QSignal mapper : Signal « Qt « C++






QSignal mapper

  


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#ifndef BUTTONWIDGET_H
#define BUTTONWIDGET_H

#include <qwidget.h>

class QSignalMapper;
class QString;
class QStringList;


class ButtonWidget : public QWidget
{
    Q_OBJECT

public:
    ButtonWidget(QStringList texts, QWidget *parent = 0);

signals:
    void clicked(const QString &text);

private:
    QSignalMapper *signalMapper;
 
};


#endif





#include <QtGui>

#include "buttonwidget.h"


ButtonWidget::ButtonWidget(QStringList texts, QWidget *parent)
    : QWidget(parent)
{
    signalMapper = new QSignalMapper(this);

    QGridLayout *gridLayout = new QGridLayout;
    for (int i = 0; i < texts.size(); ++i) {
  QPushButton *button = new QPushButton(texts[i]);
  connect(button, SIGNAL(clicked()), signalMapper, SLOT(map()));
 
  signalMapper->setMapping(button, texts[i]);
  gridLayout->addWidget(button, i / 3, i % 3);
    }

    connect(signalMapper, SIGNAL(mapped(const QString &)),
 
            this, SIGNAL(clicked(const QString &)));

    setLayout(gridLayout);
}






#include <QMainWindow>
#include <QStatusBar>

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    MainWindow()
    {
        statusBar()->showMessage(tr("Ready"));
    }

public slots:
    void buttonPressed(const QString &text)
    {
        statusBar()->showMessage(tr("Chose %1").arg(text));
    }
};





#include <QApplication>

#include "buttonwidget.h"
#include "mainwindow.h"

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    QStringList texts;
    texts << "January" << "February" << "March" << "April"
          << "May" << "June" << "July" << "August"
          << "September" << "October" << "November"
          << "December";
    MainWindow *mw = new MainWindow;
    ButtonWidget *buttons = new ButtonWidget(texts, mw);
    mw->setCentralWidget(buttons);
    mw->show();
    QObject::connect(buttons, SIGNAL(clicked(const QString &)),
                     mw, SLOT(buttonPressed(const QString &)));
    return app.exec();
}

   
    
  








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