widget.h

#ifndef WIDGET_H
#define WIDGET_H#include <QWidget>
#include <QPaintEvent>  //绘图事件class Widget : public QWidget
{Q_OBJECTpublic:Widget(QWidget *parent = 0);~Widget();void paintEvent(QPaintEvent *event);  //重写绘图事件void timerEvent(QTimerEvent *event);
private:int xPos;  //x轴坐标
};#endif // WIDGET_H

widget.cpp

#include "widget.h"
#include <QPainter>  //画家
#include <QPen>   //画笔
#include <QBrush>   //画刷
#include <QTimerEvent>
#include <QDebug>Widget::Widget(QWidget *parent): QWidget(parent),xPos(0)   //x轴坐标初始化为0
{setWindowTitle("绘图");setFixedSize(1000,800);//QWidget自带一个定时器startTimer(1000);
}Widget::~Widget()
{}//重写绘图事件
void Widget::paintEvent(QPaintEvent *event)
{//将widget主窗口作为画布QPainter painter(this);//设置画笔颜色为蓝色QPen pen(QColor(0,0,255));  //三基色：红绿蓝//设置画笔的粗细pen.setWidth(2);//设置画笔风格:点线pen.setStyle(Qt::DotLine);//设置画刷颜色为红色:填充QBrush brush(QColor(255,0,0));//设置画刷风格brush.setStyle(Qt::Dense6Pattern);painter.setPen(pen);painter.setBrush(brush);//画一条线，起始x轴y轴，终点x轴y轴painter.drawLine(0,0,100,100);//画矩形，起始x轴y轴，宽200高100painter.drawRect(100,100,200,100);//画圆painter.drawEllipse(400,100,100,100);//画椭圆painter.drawEllipse(500,100,400,100);//画浮点数的点const QPointF points[4] = {QPointF(10.1,80.2),QPointF(20.1,10.5),QPointF(70.6,40.7),QPointF(90.2,100.6)};//画多边形，多个点连接painter.drawPolygon(points,4);//画图片painter.drawPixmap(xPos++*50,400,QPixmap(":/images/luffy.png"));if(xPos*50 > this->width())   //图片移动{xPos = 0;}
}void Widget::timerEvent(QTimerEvent *event)
{qDebug() << "超时事件";//手动刷新，让窗口重绘，产生绘图事件this->update();
}

mian.cpp

#include "widget.h"
#include <QApplication>int main(int argc, char *argv[])
{QApplication a(argc, argv);Widget w;w.show();return a.exec();
}

资源文件

结果