第一种 设计界面实现
dialog.h
#ifndef DIALOG_H
#define DIALOG_H
#include <QDialog>
QT_BEGIN_NAMESPACE
namespace Ui {
class Dialog; }
QT_END_NAMESPACE
class Dialog : public QDialog
{
Q_OBJECT
public:
Dialog(QWidget *parent = nullptr);
~Dialog();
private slots:
void on_pushButton_clicked();
void on_radiusLineEdit_textChanged(const QString &arg1);
private:
Ui::Dialog *ui;
};
#endif // DIALOG_H
dialog.cpp
const static double PI=3.1416; // 声明全局变量PI
#include "dialog.h"
#include "ui_dialog.h"
Dialog::Dialog(QWidget *parent