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脚本之家。