Qt学习例子9——smile3

绘制笑脸，并使用事件

 

//smiley.h

 

#ifndef SMILEY_H

#define SMILEY_H

#include <QtGui/QWidget>

class Smiley : public QWidget

{
 

    Q_OBJECT

    Q_PROPERTY(int smileSize READ smileSize WRITE setSmileSize)

public:

    Smiley(QWidget *parent = 0);

    QSize sizeHint() const;

    int smileSize() const;

signals:

    void smileSizeChanged(int size);

public slots:

    void setSmileSize(int);

protected:

    void paintEvent(QPaintEvent *);

    void paintEye(QPainter *painter, const QPoint &pt, int size, const QPoint &focus = QPoint());

    void paintSmile(QPainter *painter, const QRect &r, int angle);

    void mousePressEvent(QMouseEvent *);

    void mouseMoveEvent(QMouseEvent *);

    void mouseReleaseEvent(QMouseEvent *);

private:

    QPoint focusPoint;

    int m_smileSize;

};

#endif // SMILEY_H

 

//smiley.cpp

 

#include "smiley.h"

#include <QPainter>

#include <QMouseEvent>

#include <cmath>

Smiley::Smiley(QWidget *parent)

    :