源程序
#include <QApplication>
#include <QWidget>
#include <QPushButton>
#include <QFont>
#include <QLCDNumber>
#include <QSlider>
class MyMainWindow : public QWidget
{
public:
MyMainWindow();
private:
QPushButton *b1;
QLCDNumber *lcd;
QSlider *slider;
};
MyMainWindow::MyMainWindow()
{
setGeometry(100,100,300,200);
b1 = new QPushButton("Quit",this);
b1->setGeometry(10,10,80,40);
b1->setFont(QFont("Times",18,QFont::Bold));
lcd = new QLCDNumber(2,this);
lcd->setGeometry(100,10,190,180);
slider = new QSlider(Vertical,this);
slider->setGeometry(10,60,80,130);
connect(b1,SIGNAL(clicked()),qApp,SLOT(quit()));
connect(slider,SIGNAL(valueChanged(int)),lcd,SLOT(display(int)));
}
void main(int argc,char **argv)
{
QApplication a(argc,argv);
MyMainWindow w;
a.setMainWidget(&w);
w.show();
a.exec();
}
程序中红色字体报错，error: 'Vertical' was not declared in this scope
error: 'class QApplication' has no member named 'setMainWidget'
a.setMainWidget(&w);这句话不是设置应用程序主窗口吗？许多书都是这个样的，把这去掉也正确。这报错怎么解决啊，求帮助！
