QT 4.7 控件间 互相发送消息例子

#include <QWidget>class WidgetTest : public QWidget

#include <qlcdnumber.h>

#include <qfont.h>

#include <QVBoxLayout>

#include <QtGui/QApplication>

{

    Q_OBJECT

public:

    explicit WidgetTest(QWidget *parent = 0);

   // ~Widget();

private:

};

WidgetTest::WidgetTest(QWidget *parent) :

    QWidget(parent)

{

    QPushButton *quit = new QPushButton( "Quit", this);

    quit->setFont(QFont("Times", 10, QFont::Bold ));

    connect( quit, SIGNAL(clicked()), qApp, SLOT(quit()) );

s

    QLCDNumber *lcd  = new QLCDNumber( 10, this);

    QSlider * slider = new QSlider(Qt::Horizontal, this);

    slider->setRange( 0, 100 );

    slider->setValue( 0 );

    QVBoxLayout* testLayout = new QVBoxLayout;

    this->setLayout(testLayout);

    testLayout->addWidget(quit);

    testLayout->addWidget(lcd);

    testLayout->addWidget(slider);

    connect( slider, SIGNAL(valueChanged(int)), lcd,SLOT(display(int)) );

}

int main(int argc, char *argv[])

{

    QApplication a(argc, argv);

    WidgetTest w(0);

    w.show();

    return a.exec();

}