原文件

#include "widget.h"
#include "ui_widget.h"

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);

    this->startTimer(1000);
}

Widget::~Widget()
{
    delete ui;
}

//时钟底座
void Widget::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);//实例化画家
    QPen pen;//实例化笔
    QFont font;//实例化字体

    //画笔属性
    pen.setWidth(5);

    //字体属性
    font.setFamily("楷体");
    font.setPointSize(10);

    //画家属性
    painter.setPen(pen);
    painter.setFont(font);
    painter.translate(this->width()/2,this->height()/2);//画家坐标

    //绘制圆
    painter.drawEllipse(QPoint(0,0),300,300);

    //绘制粗刻度
    painter.rotate(-60);
    for(int i = 0; i < 12; i++)
    {
        painter.drawLine(300,0,290,0);
        painter.rotate(30);
    }

    //绘制细刻度
    pen.setWidth(2);
    painter.setPen(pen);
    painter.rotate(-25);
    for(int i = 0; i < 72 ; i++)
    {
        painter.drawLine(300,0,295,0);
        painter.rotate(5);
    }

    //获取系统时间
    QTime time = QTime::currentTime();

    //绘制秒针
    painter.setPen(pen);
    painter.rotate(-5);
    painter.rotate(5*time.second());
    painter.drawLine(290,0,0,0);
    painter.rotate(-5*time.second());

    //绘制分针
    pen.setWidth(10);
    painter.setPen(pen);
    painter.rotate(5*time.minute());
    painter.drawLine(200,0,0,0);
    painter.rotate(-5*time.minute());

    //绘制时针
    pen.setWidth(15);
    painter.setPen(pen);
    painter.rotate(30*time.hour());
    painter.drawLine(100,0,0,0);
    qDebug()<<time.hour()<<" "<<time.minute()<<" "<<time.second();
}

void Widget::timerEvent(QTimerEvent *event)
{
    this->update();
}