如何用Java代码实现时钟效果

Java代码：

文件一：ClockPanel.java

import static java.util.Calendar.HOUR;

import static java.util.Calendar.MILLISECOND;

import static java.util.Calendar.MINUTE;

import static java.util.Calendar.SECOND;

import java.awt.BasicStroke;

import java.awt.Color;

import java.awt.Dimension;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.util.Calendar;

import javax.swing.ImageIcon;

import javax.swing.JPanel;

/**

• 时钟面板

• @author 听说你很会玩

*/

@SuppressWarnings("serial")

public class ClockPanel extends JPanel {

// 3个指针的粗细

private static final BasicStroke HOURS_POINT_WIDTH = new BasicStroke(4);

private static final BasicStroke MINUETES_POINT_WIDTH = new BasicStroke(3);

private static final BasicStroke SEC_POINT_WIDTH = new BasicStroke(2);

ImageIcon background;// 背景图片对象

private int centerX;// 中心坐标

private int centerY;// 中心坐标

private final static int secLen = 60; // 指针长度

private final static int minuesLen = 55; // 指针长度

private final static int hoursLen = 36; // 指针长度

/**

• 构造方法

*/

public ClockPanel() {

setToolTipText("小键盘+、-调整透明度，Crtl+Shift+X退出");// 提示信息Axitrader代理申请

setOpaque(false);

background = new ImageIcon(getClass().getResource("clock.jpg"));// 加载图片

int iconWidth = background.getIconWidth();// 获取图片大小

centerX = iconWidth / 2;// 获取图片中间坐标

int iconHeight = background.getIconHeight();

centerY = iconHeight / 2;// 获取图片中间坐标

setPreferredSize(new Dimension(iconWidth, iconHeight));

}

@Override

public void paint(Graphics g) {// 重写父类方法

Graphics2D g2 = (Graphics2D) g;

g2.drawImage(background.getImage(), 0, 0, this);// 绘制背景图片

Calendar calendar = Calendar.getInstance();// 获取日历对象

int millisecond = calendar.get(MILLISECOND);// 获取毫秒值

int sec = calendar.get(SECOND);// 获取秒值

int minutes = calendar.get(MINUTE);// 获取分值

int hours = calendar.get(HOUR);// 获取时值

double secAngle = (60 - sec) * 6 - (millisecond / 150); // 秒针角度

int minutesAngle = (60 - minutes) * 6;// 分针角度

int hoursAngle = (12 - hours) * 360 / 12 - (minutes / 2);// 时针角度

// 计算秒针、分针、时针指向的坐标

int secX = (int) (secLen * Math.sin(Math.toRadians(secAngle)));// 秒针指向点的X坐标

int secY = (int) (secLen * Math.cos(Math.toRadians(secAngle))); // 秒针指向点的Y坐标

int minutesX = (int) (minuesLen * Math

.sin(Math.toRadians(minutesAngle))); // 分针指向点的X坐标

int minutesY = (int) (minuesLen * Math

.cos(Math.toRadians(minutesAngle))); // 分针指向点的Y坐标

int hoursX = (int) (hoursLen * Math.sin(Math.toRadians(hoursAngle))); // 时针指向点的X坐标

int hoursY = (int) (hoursLen * Math.cos(Math.toRadians(hoursAngle))); // 时针指向点的Y坐标

// 分别绘制时针、分针、秒针

g2.setStroke(HOURS_POINT_WIDTH);// 设置时针的宽度

g2.setColor(Color.BLACK);// 设置时针的颜色

g2.drawLine(centerX, centerY, centerX - hoursX, centerY - hoursY);// 绘制时针

g2.setStroke(MINUETES_POINT_WIDTH);// 设置分针的宽度

if (minutesAngle != hoursAngle) // 分针、时针重叠变色

g2.setColor(new Color(0x2F2F2F));// 设置未重叠时的颜色

else {

g2.setColor(Color.GREEN);// 设置重叠时的颜色

}

g2.drawLine(centerX, centerY, centerX - minutesX, centerY - minutesY);// 绘制分针

g2.setStroke(SEC_POINT_WIDTH);// 设置秒针的宽度

if (secAngle != hoursAngle && secAngle != minutesAngle)// 分针、时针、秒针重叠变色

g2.setColor(Color.ORANGE);// 设置未重叠时的颜色

else {

g2.setColor(Color.GREEN);// 设置重叠时的颜色

}

// 绘制3个指针的中心圆和秒针

g2.fillOval(centerX - 5, centerY - 5, 10, 10);// 绘制中心圆

g2.drawLine(centerX, centerY, centerX - secX, centerY - secY);// 绘制秒针

g2.drawLine(centerX + 1, centerY + 1, centerX - secX + 1, centerY

• secY + 1);// 绘制秒针

}

}

文件二：ClockFrame.java

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

/**

• @author 张振坤

*/

@SuppressWarnings("serial")

public class ClockFrame extends JDialog {

private float opqua = 0.7f;

private ClockPanel clockPanel;

private Point fp; // 拖曳窗体之前的鼠标位置

public static void main(String args[]) {

EventQueue.invokeLater(new Runnable() {

public void run() {

try {

ClockFrame frame = new ClockFrame();// 创建窗体对象

frame.setVisible(true);// 显示窗体

} catch (Exception e) {

e.printStackTrace();

}

}

});

}

/**

• 布局窗体的构造方法

*/

public ClockFrame() {

super();

setUndecorated(true);// 取消窗体修饰

setAlwaysOnTop(true);// 窗体置顶

setTitle("石英钟");// 设置窗体标题

getContentPane().setLayout(new BorderLayout());

setBounds(100, 30, 217, 257);

setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);

clockPanel = new ClockPanel();// 创建时钟面板

getContentPane().add(clockPanel);

// 为时钟面板添加鼠标按键事件监听器

clockPanel.addMouseListener(new MouseAdapter() {

public void mousePressed(final MouseEvent e) {

fp = e.getPoint();

if (e.getButton()==MouseEvent.BUTTON3){

System.exit(0);// 右键退出

}

}

});

// 在时钟面板的鼠标拖曳事件中移动窗体

clockPanel.addMouseMotionListener(new MouseMotionAdapter() {

public void mouseDragged(final MouseEvent e) {

JDialog frame = (JDialog) getRootPane().getParent();

Point point = e.getLocationOnScreen();

frame.setLocation(point.x - fp.x, point.y - fp.y);

}

});

pack();

addKeyListener(new KeyAdapter() {// 为窗体添加键盘事件监听器

public void keyPressed(final KeyEvent e) {

int code = e.getKeyCode();

switch (code) {// 判断按键编码

case KeyEvent.VK_ADD:// +符号按键会降低透明图

opqua += 0.05;

opqua = opqua > 0.95f ? 1f : opqua;

break;

case KeyEvent.VK_SUBTRACT:// -符号按键会提升透明度

opqua -= 0.05;

opqua = opqua < 0.1f ? 0.1f : opqua;

break;

}

// 如果按Ctrl+Shift+X組合鍵，将退出程序

if (code == KeyEvent.VK_X

&& e.getModifiersEx() == (KeyEvent.CTRL_DOWN_MASK | KeyEvent.SHIFT_DOWN_MASK))

System.exit(0);

}

});

Dimension screenSize = getToolkit().getScreenSize();

double width = screenSize.getWidth();

int x = (int) (width - getWidth() - 30);

setLocation(x, 30);

new Thread() {// 创建线程对象，更新时钟面板界面

@Override

public void run() {

try {

while (true) {

sleep(1000);// 休眠1秒

clockPanel.repaint();// 重新绘制时钟面板界面

}

} catch (InterruptedException e) {

e.printStackTrace();

}

}

}.start();

}

}

把上面的代码赋值下来并把它粘贴到记事本保存，两个文件放在同一个文件加里，改一下文件后缀为Java。

配置Java环境就是下载JDK，这个步骤不懂的自行百度

cmd执行编译命令javac(注意：只编译ClockFrame.java文件，ClockPanel.java不编译，因为它在编译ClockFrame.java文件时，也会编译ClockPanel.java文件)

执行Java命令