2月10号作业

题目：QT实现时钟

代码：

Widget.cpp

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



Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);
    timer=startTimer(1000);
}
void Widget::timerEvent(QTimerEvent *event)
{
     if(event->timerId()==timer)
     {
         QTime time=QTime::currentTime();
         QString t=time.toString("HH:mm:ss");
         ui->lab->setText(t);
         QStringList timeList = t.split(":");
         hour=timeList[0].toUInt();
         minute=timeList[1].toUInt();
         second=timeList[2].toUInt();
         update();
         QPaintEvent *p=nullptr;
         this->paintEvent(p);

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

void Widget::paintEvent(QPaintEvent *event)
{
    QPainter p(this);
    p.setPen(Qt::black);
    p.setFont(QFont("黑体",40));

    QBrush b(QColor("yellow"));
    p.setBrush(b);

    p.translate(this->width()/2,this->height()/2);
    p.drawEllipse(QPoint(0,0),200,200);
    for (int i=0;i<60;i++)
    {
        QPen pen;
        p.setPen(QColor("black"));
        if(i%5==0)
        {
            pen.setWidth(20);
            p.drawLine(QPoint(0,200),QPoint(0,170));
        }
        else
        {
            pen.setWidth(5);
            p.drawLine(QPoint(0,200),QPoint(0,185));
        }
        p.rotate(6);
    }
    QPen pen;
    QPainter h(this);
    pen.setWidth(9);
    pen.setColor(QColor("blue"));
    h.translate(this->width()/2,this->height()/2);
    h.setPen(pen);
    h.rotate(30*hour+30*minute/60+6*second/60/12);
    h.drawLine(QPoint(0,-50),QPoint(0,20));

    QPainter m(this);
    pen.setWidth(6);
    pen.setColor(QColor("green"));
    m.translate(this->width()/2,this->height()/2);
    m.setPen(pen);
    m.rotate(6*minute+6*second/60);
    m.drawLine(QPoint(0,-100),QPoint(0,20));

    QPainter s(this);
    pen.setWidth(3);
    pen.setColor(QColor("red"));
    s.translate(this->width()/2,this->height()/2);
    s.setPen(pen);
    s.rotate(6*second);
    s.drawLine(QPoint(0,-150),QPoint(0,20));
}

Widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include<QPainter>
#include<QPaintEvent>
#include<QDebug>
#include<QTimerEvent>       //定时器事件
#include<QTime>             //时间类
#include<QDebug>
#include<QTimer>          //定时器类
#include<QDateTime>          //日期时间类

QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACE

class Widget : public QWidget
{
    Q_OBJECT
protected:
    //重写定时器事件处理函数
    void timerEvent(QTimerEvent *event)override;
public:
    Widget(QWidget *parent = nullptr);
    ~Widget();
void paintEvent(QPaintEvent *event) override;
private:
    Ui::Widget *ui;
    int timer;
    quint8 hour;
    quint8 minute;
    quint8 second;
};
#endif // WIDGET_H

运行结果：