java —— 绘制跟随窗口大小变化的立方体+菜单切换图形

这里绘制了一个五角星和一个随窗口大小变化的立方体，然后通过菜单进行切换
java中有直接绘制矩形的函数，但是这里就直接用直线构造，将每个点的坐标都化作窗口宽度的几分之几，这样就可以随之变化啦，当时函数也可以实现，只要我们构造点的时候采用相对坐标就行

立方体

package poly;
import java.awt.*;
import java.awt.geom.*;
import java.util.*;
import javax.swing.*;
public class cubeShape extends JPanel{
    public void paintComponent(Graphics g)
    {
        super.paintComponent(g);
        Graphics2D g2d = (Graphics2D) g;

        double x1=2*this.getWidth()/15; 
        double y1=2*this.getHeight()/15;
        double x2=12*this.getWidth()/15;
        double y2=2*this.getHeight()/15;
        double x3=4*this.getWidth()/15; 
        double y3=4*this.getHeight()/15;
        double x4=14*this.getWidth()/15;    
        double y4=4*this.getHeight()/15;
        double x5=2*this.getWidth()/15; 
        double y5=12*this.getHeight()/15;
        double x6=12*this.getWidth()/15;    
        double y6=12*this.getHeight()/15;
        double x7=4*this.getWidth()/15; 
        double y7=14*this.getHeight()/15;
        double x8=14*this.getWidth()/15;    
        double y8=14*this.getHeight()/15;
        g2d.setPaint(Color.blue);
        g2d.setStroke(new BasicStroke(2.f));
        g2d.draw(new Line2D.Double(x1,y1,x2,y2));
        g2d.draw(new Line2D.Double(x1,y1,x3,y3));
        g2d.draw(new Line2D.Double(x1,y1,x5,y5));
        g2d.draw(new Line2D.Double(x1,y1,x2,y2));
        g2d.draw(new Line2D.Double(x7,y7,x5,y5));
        g2d.draw(new Line2D.Double(x7,y7,x3,y3));
        g2d.draw(new Line2D.Double(x7,y7,x8,y8));
        g2d.draw(new Line2D.Double(x4,y4,x3,y3));
        g2d.draw(new Line2D.Double(x4,y4,x8,y8));
        g2d.draw(new Line2D.Double(x4,y4,x2,y2));
        float[] dashes= {10};
        g2d.setPaint(Color.BLACK);
        g2d.setStroke (new BasicStroke(1, BasicStroke.CAP_ROUND,BasicStroke.JOIN_ROUND, 10, dashes, 0));
        g2d.draw(new Line2D.Double(x6,y6,x5,y5));
        g2d.draw(new Line2D.Double(x6,y6,x8,y8));
        g2d.draw(new Line2D.Double(x6,y6,x2,y2));

    }
}

五角星

package poly;
import java.awt.*;
import java.awt.geom.*;
import java.util.*;
import javax.swing.*;
public class Shape2JPnel extends JPanel{
    public void paintComponent(Graphics g)
    {
        super.paintComponent(g);
        //Random random = new Random();
        int[] xPoints = {55,67,109,73,83,55,27,37,1,43};
        int[] yPoints = {0,36,36,54,96,72,96,54,36,36};
        Graphics2D g2d = (Graphics2D) g;
        GeneralPath star = new GeneralPath();
        star.moveTo(xPoints[0], yPoints[0]);
        for(int cnt=1;cnt100, 100);
        g2d.setColor(new Color(61,89,171));
        g2d.fill(star);
    }
}

主程序

package poly;
import javax.swing.JPanel;
import javax.swing.JFrame;
import java.awt.event.*;  
import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.geom.*;
public class shape2 {
    public static void main (String[] args ){
        JFrame frame = new JFrame ("");
        frame.setSize (315,350);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        frame.setVisible (true);
        cubeShape p = new cubeShape();
        Shape2JPnel s = new Shape2JPnel();
        JMenuBar menuBar = new JMenuBar ();
        JMenu fileMenu = new JMenu ("菜单");
        menuBar .add(fileMenu);
        JMenuItem rectMenuItem = new JMenuItem("正方体");
        JMenuItem StarMenuItem = new JMenuItem("五角星");
        fileMenu .add(rectMenuItem);
        fileMenu .add(StarMenuItem);
        frame.add (p);
        p.setVisible (false);
        frame.add(s);
        s.setVisible (false);
        JButton b1 = new JButton("正方体");
        JButton b2 = new JButton ("五角星");
        rectMenuItem .addActionListener (new ActionListener() {
            public void actionPerformed (ActionEvent e) {
                frame.remove (s);
                frame.add (p);
                p.setVisible (true);
                s.setVisible(false);
            }
        });
        StarMenuItem.addActionListener (new ActionListener (){
            public void actionPerformed (ActionEvent e) {
                frame.remove(p);
                frame.add(s);
                s.setVisible (true);
                p.setVisible(false);
            }
        });
        frame .setJMenuBar (menuBar);

        //frame.setLayout(new FlowLayout());
        //frame.setLayout(null);
        frame.setVisible (true);
    }

}