drawgraphicsdemo.java

JAVA编程思想源代码 值得一下 很难找的

package chapter11;

import java.awt.Color;
import java.awt.Container;
import java.awt.Graphics;
import java.awt.Polygon;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class DrawGraphicsDemo extends JFrame {
	public DrawGraphicsDemo() {
		setTitle("DrawGraphicsDemo ");
		setSize(WIDTH, HEIGHT);

		// 将panel加入到frame
		DrawPanel panel = new DrawPanel();
		Container contentPane = getContentPane();
		contentPane.add(panel);
	}

	public static final int WIDTH = 300;

	public static final int HEIGHT = 200;

	public static void main(String[] args) {

		DrawGraphicsDemo frame = new DrawGraphicsDemo();
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setVisible(true);
	}

}

class DrawPanel extends JPanel {
	public void paintComponent(Graphics g) {
		super.paintComponent(g);

		int x1 = 50;
		int y1 = 50;
		int x2 = 50;
		int y2 = 150;
		int radius = 100; // 半径
		int startAngle = -90; // 起始角度
		int arcAngle = 180; // 弧的角度

		// 画线
		g.drawLine(x1, y1, x2, y2);
		g.drawRect(20, 20, 50, 50);
		g.setColor(Color.RED);

		// 画弧
		g.drawArc(x1 - radius / 2, y1, radius, radius, startAngle, arcAngle);

		int x[] = { 90, 150, 140, 90 };
		int y[] = { 130, 140, 170, 170 };
		g.drawPolygon(x, y, 4);

		g.drawOval(160, 130, 60, 40);
		g.fillOval(230, 130, 60, 40);
	}
}