1、新建QT GUI工程，项目名称“ShapeWidget”, 基类QWidget， 类名ShapeWidget，取消“创建界面”

2、ShapeWidget.h

#ifndef SHAPEWIDGET_H#define SHAPEWIDGET_H#include 
    
     class ShapeWidget : public QWidget{    Q_OBJECTpublic:    ShapeWidget(QWidget *parent = 0);    ~ShapeWidget();protected:    void mousePressEvent(QMouseEvent *);    void mouseMoveEvent(QMouseEvent *);    void paintEvent(QPaintEvent *);private:    QPoint dragPosition;};#endif // SHAPEWIDGET_H
    

3、

#include "shapewidget.h"#include 
    
     #include 
     
      #include 
      
       #include 
       
        ShapeWidget::ShapeWidget(QWidget *parent)    : QWidget(parent){    QPixmap pix;    pix.load("F:\\MyCode\\test1.bmp", 0, Qt::AvoidDither|Qt::ThresholdDither|Qt::ThresholdAlphaDither);    resize(pix.size());    setMask(QBitmap(pix.mask()));}ShapeWidget::~ShapeWidget(){}void ShapeWidget::mousePressEvent(QMouseEvent *event){    if(event->button()==Qt::LeftButton)    {        dragPosition =event->globalPos()-frameGeometry().topLeft();        event->accept();    }    if(event->button()==Qt::RightButton)    {        close();    }}void ShapeWidget::mouseMoveEvent(QMouseEvent *event){    if(event->buttons()&Qt::LeftButton)    {        move(event->globalPos()-dragPosition);        event->accept();    }}void ShapeWidget::paintEvent(QPaintEvent *event){    QPainter painter(this);    painter.drawPixmap(0,0,QPixmap("F:\\MyCode\\test1.bmp"));}