H

#pragma once

#include <QWidget>
#include <QApplication>
#include <QPushButton>
#include <QLabel>
#include <QPainter>

class Degree : public QWidget
{
    Q_OBJECT

    // это подкласс, можно запихать внутрь

    class Drawer
    {
      Q_OBJECT

    public:
       Drawer(QWidget* parent) : painter(parent)  {}
      ~Drawer() { delete painter }

        void draw();

        QPainter* painter
    };

public:
    Degree(QWidget* parent = 0) : drawer(parent) {}
    void draw() { drawer.painter.draw(); }

private:
    Drawer drawer;

};