Java AWT（Applet）应用示例 - 持续更新

import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class ArcTest extends Applet implements WindowListener{
	ArcControls controls;
	
	public static void main(String args[]){
		Frame f = new Frame("ArcTest");
		ArcTest arcTest = new ArcTest();
		
		arcTest.init();
		arcTest.start();
		
		f.add("Center", arcTest);
		f.setSize(300, 300);
		f.addWindowListener(arcTest);
		
		//f.show();
		f.setVisible(true);
    }
	
	//Override Applet Methods
	@Override
	public void init(){
		setLayout(new BorderLayout());
		ArcCanvas c = new ArcCanvas();
		add("Center", c);
		add("South", controls = new ArcControls(c));
	}
	
	@Override
	public void start(){
		controls.setEnabled(true);
	}
	
	@Override
	public void stop(){
		controls.setEnabled(false);
	}
	
	//Override WindowListener Methods
	@Override
    public void windowActivated(WindowEvent e)//当窗口从非激活到激活状态时监视器调用该方法
    {
    }

    @Override
    public void windowClosed(WindowEvent e)//当窗口关闭时
    {
    }

    @Override
    public void windowClosing(WindowEvent e)//窗口正被关闭
    {
        // 退出
        System.exit(0);
    }

    @Override
    public void windowDeactivated(WindowEvent e)//激活到非激活状态
    {
    }

    @Override
    public void windowDeiconified(WindowEvent e)//当窗口撤销图标化时
    {
    }

    @Override
    public void windowIconified(WindowEvent e)//当窗口图标化时
    {
    }

    @Override
    public void windowOpened(WindowEvent e)//当窗口打开时
    {
    }
}

class ArcCanvas extends Canvas{
	int startAngle = 0;
	int endAngle = 45;
	boolean filled = false;
	Font font;
	
	public void paint(Graphics g){
		Rectangle r = getBounds();
		int hlines = r.height / 10;
		int vlines = r.width /10;

		System.out.print("height = ");
		System.out.println(r.height);
		System.out.print("nwidth = ");
		System.out.println(r.width);
		
		g.setColor(Color.pink);
		
		for (int i = 1; i <= hlines; i++){
			g.drawLine(0, i*10, r.width, i*10);
		}
		
		for (int i = 1; i<= vlines; i++){
			g.drawLine(i*10, 0, i*10, r.height);
		}
		
		g.setColor(Color.red);
		if (filled){
			g.fillArc(0, 0, r.width-1, r.height-1, startAngle, endAngle);
		} else {
			g.drawArc(0, 0, r.width-1, r.height-1, startAngle, endAngle);
		}
		
		g.setColor(Color.black);
		g.setFont(font);
		g.drawLine(0, r.height/2, r.width, r.height/2);
		g.drawLine(r.width/2, 0, r.width/2, r.height);
		g.drawLine(0, 0, r.width, r.height);
		g.drawLine(r.width, 0, 0, r.height);
		
		int sx = 10;
		int sy = r.height - 28;
		g.drawString("S = " + startAngle, sx, sy);
		g.drawString("N = " + endAngle, sx, sy + 14);
	}
	
	public void redraw(boolean filled, int start, int end){
		this.filled = filled;
		this.startAngle = start;
		this.endAngle = end;
		repaint();
	}
}

class ArcControls extends Panel implements ActionListener{
	TextField s;
	TextField e;
	ArcCanvas canvas;
	
	public ArcControls(ArcCanvas canvas){
		Button b = null;
		this.canvas = canvas;
		
		add(s = new TextField("30", 4));
		add(e = new TextField("90", 4));
		
		b = new Button("Fill");
		b.addActionListener(this);
		add(b);
		
		b = new Button("Draw");
		b.addActionListener(this);
		add(b);
		
		canvas.redraw(true, 
			         Integer.parseInt(s.getText().trim()),
					 Integer.parseInt(e.getText().trim()));
	}
	
	@Override
	public void actionPerformed(ActionEvent ev){
		String label = ev.getActionCommand();
		System.out.println(label);
		
		canvas.redraw(label.equals("Fill"),
		             Integer.parseInt(s.getText().trim()),
					 Integer.parseInt(e.getText().trim()));
	}
}

javac -encoding UTF-8 -Xlint:deprecation ArcTest.java

jar cvf ArcTest.jar ArcControls.class ArcCanvas.class ArcTest.class 

java ArcTest