C++ GUI Qt4编程笔记1

信号和槽，以及简单布局

#include <QApplication>#include <QHBoxLayout>#include <QSlider>#include <QSpinBox>int main(int argc, char *argv[]){    QApplication app(argc, argv);    QWidget *window = new QWidget;    window->setWindowTitle("Enter Your Age");    QSpinBox *spinBox = new QSpinBox;    QSlider *slider = new QSlider(Qt::Horizontal);    spinBox->setRange(0,130);    slider->setRange(0,130);    QObject::connect(spinBox,SIGNAL(valueChanged(int)),                     slider,SLOT(setValue(int)));    QObject::connect(slider,SIGNAL(valueChanged(int)),                     spinBox,SLOT(setValue(int)));    spinBox->setValue(35);    QHBoxLayout *layout = new QHBoxLayout;    layout->addWidget((spinBox));    layout->addWidget(slider);    window->setLayout(layout);    window->show();    return app.exec();}