java模拟时钟工作,但需要几秒钟重新绘制
我制作了一个模拟时钟,它在工作,但当一个删除圆角(背景)的秒针不断重复自己,但当我添加圆角时,它在工作。但我不想看到背景。谢谢
这是密码
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Clock extends JPanel implements Runnable {
Thread thread = null;
SimpleDateFormat formatter = new SimpleDateFormat("s", Locale.getDefault());
Date currentDate;
int xcenter = 175, ycenter = 175, lastxs = 0, lastys = 0, lastxm = 0, lastym = 0, lastxh = 0, lastyh = 0;
private void drawStructure(Graphics g) {
g.setFont(new Font("TimesRoman", Font.BOLD, 20));
g.setColor(Color.black);
//g.fillOval(xcenter - 150, ycenter - 150, 300, 300);
g.setColor(Color.blue);
g.setColor(Color.green);
g.drawString("9", xcenter - 145, ycenter + 0);
g.drawString("3", xcenter + 135, ycenter + 0);
g.drawString("12", xcenter - 10, ycenter - 130);
g.drawString("6", xcenter - 10, ycenter + 145);
}
public void paint(Graphics g) {
int xhour, yhour, xminute, yminute, xsecond, ysecond, second, minute, hour;
drawStructure(g);
currentDate = new Date();
formatter.applyPattern("s");
second = Integer.parseInt(formatter.format(currentDate));
formatter.applyPattern("m");
minute = Integer.parseInt(formatter.format(currentDate));
formatter.applyPattern("h");
hour = Integer.parseInt(formatter.format(currentDate));
xsecond = (int) (Math.cos(second * 3.14f / 30 - 3.14f / 2) * 120 + xcenter);
ysecond = (int) (Math.sin(second * 3.14f / 30 - 3.14f / 2) * 120 + ycenter);
xminute = (int) (Math.cos(minute * 3.14f / 30 - 3.14f / 2) * 100 + xcenter);
yminute = (int) (Math.sin(minute * 3.14f / 30 - 3.14f / 2) * 100 + ycenter);
xhour = (int) (Math.cos((hour * 30 + minute / 2) * 3.14f / 180 - 3.14f / 2) * 80 + xcenter);
yhour = (int) (Math.sin((hour * 30 + minute / 2) * 3.14f / 180 - 3.14f / 2) * 80 + ycenter);
// Erase if necessary, and redraw
g.drawLine(xcenter, ycenter, xsecond, ysecond);
g.setColor(Color.red);
g.drawLine(xcenter, ycenter - 1, xminute, yminute);
g.drawLine(xcenter - 1, ycenter, xminute, yminute);
g.setColor(Color.green);
g.drawLine(xcenter, ycenter - 1, xhour, yhour);
g.drawLine(xcenter - 1, ycenter, xhour, yhour);
lastxs = xsecond;
lastys = ysecond;
lastxm = xminute;
lastym = yminute;
lastxh = xhour;
lastyh = yhour;
}
public void start() {
if (thread == null) {
thread = new Thread(this);
thread.start();
}
}
public void stop() {
thread = null;
}
public void run() {
while (thread != null) {
try {
Thread.sleep(100);
} catch (InterruptedException e) {
}
repaint();
}
thread = null;
}
public void update(Graphics g) {
paint(g);
}
public static void main(String args[]) {
JFrame frame = new JFrame();
Color c = new Color(118, 73, 190);
frame.setBackground(c);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setBounds(0, 0, 400, 400);
Clock clock = new Clock();
frame.getContentPane().add(clock);
frame.setVisible(true);
}
}
# 1 楼答案
Swing程序应该重写^{} ,而不是重写
paint()
。此外,调用super.paintComponent()
以避免这种呈现artifact。类似的问题在这个相关的example中得到了说明。还有一些补充意见:Swing程序应该在event dispatch thread上构建和更新
使用Swing timer更新显示
经测试: