QT绘时钟

#ifndef MAINWINDOW_H#define MAINWINDOW_H#include <QMainWindow>#include <QGroupBox>namespace Ui {class MainWindow;}class MainWindow : public QMainWindow{    Q_OBJECTpublic:    explicit MainWindow(QWidget *parent = 0);    ~MainWindow(); void paintEvent(QPaintEvent *event); QRectF textRectF(double radius, int pointSize, double angle);private:    Ui::MainWindow *ui;};#endif // MAINWINDOW_H

#include "mainwindow.h"#include "ui_mainwindow.h"#include <QGridLayout>#include"math.h"#include <QRectF>#include <QPainter>#include <QTimer>#include <QTime>#include <QPaintEvent>#include <QDebug>#include <complex>#include <QPoint>using namespace std;MainWindow::MainWindow(QWidget *parent) :    QMainWindow(parent),    ui(new Ui::MainWindow){    ui->setupUi(this);    QTimer *timer = new QTimer(this);    connect(timer, SIGNAL(timeout()), this, SLOT(update()));    timer->start(1000);}MainWindow::~MainWindow(){    delete ui;}QRectF MainWindow::textRectF(double radius, int pointSize, double angle){    qDebug()<<angle;        qDebug()<<radius;            qDebug()<<pointSize;    QRectF rectF;    rectF.setX(radius*cos(angle*3.1415/180.0) - pointSize*2);    rectF.setY(radius*sin(angle*3.1415/180.0) - pointSize/2.0);    rectF.setWidth(pointSize*4);    rectF.setHeight(pointSize);    return rectF;}void MainWindow::paintEvent(QPaintEvent *event){    Q_UNUSED(event);    // 时针、分针、秒针位置 - 多边形     static const QPoint hourHand[3] = {         QPoint(7, 8),        QPoint(-7, 8),        QPoint(0, -30)    };    static const QPoint minuteHand[3] = {        QPoint(7, 8),        QPoint(-7, 8),        QPoint(0, -65)    };    static const QPoint secondHand[3] = {        QPoint(7, 8),        QPoint(-7, 8),        QPoint(0, -80)    };    // 时针、分针、秒针颜色    QColor hourColor(200, 100, 0, 200);    QColor minuteColor(0, 127, 127, 150);    QColor secondColor(0, 160, 230, 150);    int side = qMin(width(), height());    QTime time = QTime::currentTime();    QPainter painter(this);    painter.setRenderHint(QPainter::Antialiasing);    // 平移坐标系原点至中心点    painter.translate(width() / 2, height() / 2);    // 缩放    painter.scale(side / 200.0, side / 200.0);    // 绘制时针    painter.setPen(Qt::NoPen);    painter.setBrush(hourColor);    painter.save();    // 每圈360° = 12h 即：旋转角度 = 小时数 * 30°    painter.rotate(30.0 * ((time.hour() + time.minute() / 60.0)));    painter.drawConvexPolygon(hourHand, 3);    painter.restore();    painter.setPen(hourColor);    // 绘制小时线 （360度 / 12 = 30度）    for (int i = 0; i < 12; ++i) {        painter.drawLine(88, 0, 96, 0);        painter.rotate(30.0);    }    int radius = 100;    QFont font = painter.font();    font.setBold(true);    painter.setFont(font);    int pointSize = font.pointSize();    // 绘制小时文本    int nHour = 0;    for (int i = 0; i < 12; ++i) {        nHour = i + 3;        if (nHour > 12)            nHour -= 12;         painter.drawText(textRectF(radius*0.8, pointSize, i * 30), Qt::AlignCenter, QString::number(nHour));    }    // 绘制分针    painter.setPen(Qt::NoPen);    painter.setBrush(minuteColor);    painter.save();    // 每圈360° = 60m 即：旋转角度 = 分钟数 * 6°    painter.rotate(6.0 * (time.minute() + time.second() / 60.0));    painter.drawConvexPolygon(minuteHand, 3);    painter.restore();    painter.setPen(minuteColor);    // 绘制分钟线 （360度 / 60 = 6度）    for (int j = 0; j < 60; ++j) {        if ((j % 5) != 0)            painter.drawLine(92, 0, 96, 0);        painter.rotate(6.0);    }    // 绘制秒针    painter.setPen(Qt::NoPen);    painter.setBrush(secondColor);    painter.save();    // 每圈360° = 60s 即：旋转角度 = 秒数 * 6°    painter.rotate(6.0 * time.second());    painter.drawConvexPolygon(secondHand, 3);    painter.restore();}