本文实例为大家分享了Qt实现简单动态时钟的具体代码，供大家参考，具体内容如下
任务实现：
通过Qt语言使用计时器实现一个简单的动态时钟；
实现效果：
实现过程：
整体过程主要分为两个部分：
1.绘制一个表盘所需的元素：时分秒针，刻度，还可以插入钟面背景图片；
2.让所绘制的指针动起来（使用计时器并关联系统时间）；
整体代码：
dialog.h
#ifndef DIALOG_H
#define DIALOG_H
#include <QDialog>
QT_BEGIN_NAMESPACE
namespace Ui { class Dialog; }
QT_END_NAMESPACE
class Dialog : public QDialog
{
Q_OBJECT
public:
Dialog(QWidget *parent = nullptr);
~Dialog();
void paintEvent(QPaintEvent *event);
void drawSecond(QPainter *painter);
void drawMinute(QPainter *painter);
void drawHour(QPainter *painter);
void drawClock(QPainter *painter);
private:
Ui::Dialog *ui;
};
#endif // DIALOG_H
dialog.cpp
#include "dialog.h"
#include "ui_dialog.h"
#include <QPainter>
#include <QTime>
#include <QTimer>
#include <QPixmap>
#include <QPen>
Dialog::Dialog(QWidget *parent)
: QDialog(parent)
, ui(new Ui::Dialog)
{
ui->setupUi(this);
resize(959,959);
setWindowTitle("My Clock");
QTimer *timer = new QTimer(this);
timer->start(1000);
//信号的链接
connect(timer,SIGNAL(timeout()),this,SLOT(update()));
}
Dialog::~Dialog()
{
delete ui;
}
void Dialog::paintEvent(QPaintEvent *event)
{
QPainter painter(this);
QPixmap map(":/Resrouse/Pic.jpg");
QRect q(0,0,959,959);
QRect q2(0,0,width(),height());
painter.drawPixmap(q2,map,q);
//防止图形走样
painter.setRenderHint(QPainter::Antialiasing,true);
//使得窗口可调节，图形随之变形
painter.setWindow(0,0,200,200);
//重新设置坐标轴的原点位置
painter.translate(100,100);
//调用绘制图像函数，分别绘制时分秒
drawClock(&painter);
drawSecond(&painter);
drawMinute(&painter);
drawHour(&painter);
}
void Dialog::drawSecond(QPainter *painter)
{
static const QPoint Second[4]=
{
QPoint(2, 5),
QPoint(0, 18),
QPoint(-2, 5),
QPoint(0, -90)
};
//获取当前系统时间currentTime();
QTime time = QTime::currentTime();
//设置绘制颜色
painter->setBrush(Qt::red);
painter->setPen(Qt::red);
//save进行保存
painter->save();
//完成绘制（时间换算倾斜角度）
painter->rotate(6.0*time.second());
painter->drawConvexPolygon(Second,4);
//ratate进行复位
painter->restore();
}
void Dialog::drawMinute(QPainter *painter)
{
static const QPoint Minute[4]=
{
QPoint(2, 5),
QPoint(0, 16),
QPoint(-2, 5),
QPoint(0, -70)
};
QTime time = QTime::currentTime();
painter->setBrush(Qt::blue);
painter->setPen(Qt::blue);
painter->save();
painter->rotate(6.0*(time.minute()+time.second()/60.0));
painter->drawConvexPolygon(Minute,4);
painter->restore();
}
void Dialog::drawHour(QPainter *painter)
{
static const QPoint Hour[4]=
{
QPoint(2, 5),
QPoint(0, 13),
QPoint(-2, 5),
QPoint(0, -40)
};
QTime time = QTime::currentTime();
painter->setBrush(Qt::yellow);
painter->setPen(Qt::yellow);
painter->save();
painter->rotate(30.0*(time.hour()+time.minute()/60.0));
painter->drawConvexPolygon(Hour,4);
painter->restore();
}
void Dialog::drawClock(QPainter *painter)
{
QPen pen;
pen.setWidth(2);
pen.setColor(Qt::white);
painter->setPen(pen);
//绘制钟表刻度盘和数字
for (int i = 1; i <=60; ++i)
{
painter->save();
painter->rotate(6*i);//坐标轴旋转6度
//分别绘制长短线
if (i % 5 == 0)
{
painter->drawLine(0, -98, 0, -82);
painter->drawText(-20, -82, 40, 40,Qt::AlignHCenter | Qt::AlignTop,QString::number(i/5));
}
else
{
painter->drawLine(0, -98, 0, -88);
}
painter->restore();//绘制图形后复位坐标系
}
}
表盘绘制：
使用paintEvent（）函数，以结构体形式来储存每一个指针的大小位置，并进行绘制；
下面用秒针的绘制作为例子：
void Dialog::drawSecond(QPainter *painter)
{
static const QPoint Second[4]=
{
QPoint(3, 5),
QPoint(0, 18),
QPoint(-3, 5),
QPoint(0, -90)
};
//获取当前系统时间currentTime();
QTime time = QTime::currentTime();
//设置绘制颜色
painter->setBrush(Qt::red);
painter->setPen(Qt::red);
//save进行保存
painter->save();
//完成绘制（时间换算倾斜角度）
painter->rotate(6.0*time.second());
painter->drawConvexPolygon(Second,4);
//ratate进行复位
painter->restore();
}
调用时间：
设置计时器的时间为1000ms，即1s；
QTimer *timer = new QTimer(this); timer->start(1000); //信号的链接 connect(timer,SIGNAL(timeout()),this,SLOT(update()));
其他：
1.图片的插入：
map中内容可替换为自行导入的资源文件
QPixmap map(":/Resrouse/Pic.jpg");
QRect q(0,0,959,959);
QRect q2(0,0,width(),height());
painter.drawPixmap(q2,map,q);
2.绘制颜色的改变：
QPen pen; //设置画笔的宽度 pen.setWidth(2); //设置画笔的颜色 pen.setColor(Qt::white); //调用设置的画笔参数 painter->setPen(pen);
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持免费资源网。
