import java.awt.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.event.*;
import javax.swing.*;
import javax.swing.Timer;
/**
* <p>Title: 時鐘</p>
* <p>Description: 本實例演示使用圖形繪制一個圖形時鐘</p>
* <p>Copyright: Copyright (c) 2003</p>
* <p>Filename: Clock.java</p>
* @version 1.0
*/
public class Clock extends JFrame implements ActionListener{
Timer timer;
int x,y,old_X,old_Y, r,x0,y0,w,h,ang;
int sdo,mdo,hdo,old_M,old_H;
TimeZone tz =TimeZone.getTimeZone("JST");
final double RAD=Math.PI/180.0;
public static void main(String[] args){
Clock cl = new Clock();
}
/**
*<br>方法說明：實現ActionListener類必須過載的方法
*<br>輸入參數：
*<br>返回類型：
*/
public void actionPerformed(ActionEvent e) {
timer.restart();
}
/**
*<br>方法說明：構造器，顯示窗體，並添加了一個秒表
*<br>輸入參數：
*<br>返回類型：
*/
Clock(){
super("Clock");
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
setBackground(new Color(0,0,192));
setSize(300,300);
show();
int delay = 1000;
//窗體添加事件監聽，監聽秒表的觸發
ActionListener taskPerformer = new ActionListener() {
public void actionPerformed(ActionEvent evt) {
repaint();
}
};
new Timer(delay, taskPerformer).start();
}
/**
*<br>方法說明：繪制圖形
*<br>輸入參數：
*<br>返回類型：
*/
public void paint( Graphics g ) {
Insets insets = getInsets();
int L0 = (insets.left)/2, T0 = (insets.top)/2;
int hh,mm,ss;
String st;
h=getSize().height;
//繪制圓形
g.setColor(Color.white);
g.drawOval(L0+30,T0+30,h-60,h-60);
g.drawOval(L0+32,T0+32,h-64,h-64);
r=h/2-30;
x0=30+r-5+L0;
y0=30+r-5-T0;
ang=60;
for (int i=1; i<=12; i++) {
x=(int)((r+10)*Math.cos(RAD*ang)+x0);
y=(int)((r+10)*Math.sin(RAD*ang)+y0);
g.drawString(""+i,x,h-y);
ang-=30;
}
x0=30+r+L0; y0=30+r+T0;
//獲取時間
Calendar now=Calendar.getInstance();
hh=now.get(Calendar.HOUR_OF_DAY);//小時
mm=now.get(Calendar.MINUTE);//分鐘
ss=now.get(Calendar.SECOND);// 秒
g.setColor(Color.pink);
g.fillRect(L0,T0,60,28);//填充的矩形
g.setColor(Color.blue);
if (hh < 10) st="0"+hh; else st=""+hh;
if (mm < 10) st=st+":0"+mm; else st=st+":"+mm;
if (ss < 10) st=st+":0"+ss; else st=st+":"+ss;
g.drawString(st,L0,T0+25);
//計算時間和圖形的關系
sdo=90-ss*6;
mdo=90-mm*6;
hdo=90-hh*30-mm/2;
//擦除秒針
if (old_X > 0) {
g.setColor(getBackground());
g.drawLine(x0,y0,old_X,(h-old_Y));
} else {
old_M=mdo;
old_H=hdo;
}
//繪制秒針
g.setColor(Color.yellow);
x=(int)((r-8)*Math.cos(RAD*sdo)+x0);
y=(int)((r-8)*Math.sin(RAD*sdo)+y0)-2*T0;
g.drawLine(x0,y0,x,(h-y));
old_X=x;
old_Y=y;
//擦除分針和時針
if (mdo != old_M) {
line(g,old_M,(int)(r*0.7),getBackground());
old_M=mdo;
}
if (hdo != old_H) {
line(g,old_H,(int)(r*0.5),getBackground());
old_H=hdo;
}
//繪制分針
line(g,mdo,(int)(r*0.7),Color.green);
//繪制時針
line(g,hdo,(int)(r*0.5),Color.red);
} // end paint
/**
*<br>方法說明：繪制線，用於繪制時針和分針
*<br>輸入參數：
*<br>返回類型：
*/
public void line(Graphics g, int t, int n, Color c) {
int [] xp = new int[4];
int [] yp = new int[4];
xp[0]=x0;
yp[0]=y0;
xp[1]= (int)((n-10)*Math.cos(RAD*(t-4))+x0);
yp[1]=h-(int)((n-10)*Math.sin(RAD*(t-4))+y0);
xp[2]= (int)( n *Math.cos(RAD* t )+x0);
yp[2]=h-(int)( n *Math.sin(RAD* t )+y0);
xp[3]= (int)((n-10)*Math.cos(RAD*(t+4))+x0);
yp[3]=h-(int)((n-10)*Math.sin(RAD*(t+4))+y0);
g.setColor(c);
g.fillPolygon(xp,yp,4);
}
}
