{

QApplication a(argc, argv);

//Main window widget

QWidget *mainw = new QWidget;

mainw->setWindowTitle("first qt window");

//spinbox & slider

QSpinBox *spin = new QSpinBox;

QSpinBox *spin2 = new QSpinBox;

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

spin->setRange(1,50);

spin2->setRange(51,100);

slider->setRange(1,50);

QObject::connect(spin, SIGNAL(valueChanged(int)),slider,SLOT(setValue(int)));

QObject::connect(spin2, SIGNAL(valueChanged(int)),slider,SLOT(setValue(int)));

QObject::connect(slider, SIGNAL(valueChanged(int)),spin,SLOT(setValue(int)));

spin->setValue(10);

spin->setValue(60);

slider->setValue(10);

//Label

QLabel *qlable = new QLabel("Hello this is Lable");

//Push button

QPushButton *qpush = new QPushButton("quit me");

QPushButton *qpush2 = new QPushButton("clicking me");

//qpush->show();

QObject::connect(qpush,SIGNAL(clicked()),&a,SLOT(quit()));

QObject::connect(qpush2,SIGNAL(clicked()),&a,SLOT(quit()));

// qlable->show();

//Create layout

QHBoxLayout *layout = new QHBoxLayout;

//add widget to layout

layout->addWidget(spin);

layout->addWidget(spin2);

layout->addWidget(slider);

layout->addWidget(qlable);

layout->addWidget(qpush);

layout->addWidget(qpush2);

//set layout for main window

mainw->setLayout(layout);

mainw->show();

MainWindow w;

w.show();

return a.exec();