Qt阴影效果

1.   Widget.h

#ifndef WIDGET_H

#define WIDGET_H

#include <QWidget>

#include <QPainter>

#include <QMouseEvent>

namespace Ui {
 
 

class Widget;

}

class Widget : public QWidget

{
 
 

    Q_OBJECT

public:

    explicit Widget(QWidget *parent = 0);

    ~Widget();

    void loseMouse();

    void paintEvent(QPaintEvent *event);

    void mouseReleaseEvent(QMouseEvent *event);

    void mouseMoveEvent(QMouseEvent *event);

    void mousePressEvent(QMouseEvent