Draw line

[janes]

Hi, I would need help, pleas. I would like draw the line with the specified angles, with the repeat and the number of segments. Will you help me please?

now I have this:

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.HeadlessException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

/**
*
* @author martin.juranek
*/
public class Main extends JFrame {

private boolean draw = false;
JPanel paintPanel;

public Main() throws HeadlessException {
JButton jb = new JButton("Cudl");
jb.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {
draw = true;
System.out.println("kresli = " + draw);
paintPanel.repaint();

}
});
paintPanel = new JPanel() {

@Override
public void paint(Graphics g) {
super.paint(g);
if (draw) {
g.drawLine(0, 0, 1000, 1000);
} else {
}
}
};
BorderLayout bl = new BorderLayout();
bl.addLayoutComponent(jb, BorderLayout.NORTH);
bl.addLayoutComponent(paintPanel, BorderLayout.CENTER);
getContentPane().add(jb);
getContentPane().add(paintPanel);
setLayout(bl);
paintPanel.setPreferredSize(new Dimension(500, 500));
jb.setPreferredSize(new Dimension(50, 100));

pack();
}

/**
* @param args the command line arguments
*/
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {

public void run() {
Main m = new Main();
m.setVisible(true);
}
});
// TODO code application logic here
}
}

[hardwired]

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class MainLine extends JFrame {
    private boolean draw = false;
    JPanel paintPanel;

    public MainLine() throws HeadlessException {
        JButton jb = new JButton("Cudl");
        jb.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                draw = true;
                System.out.println("kresli = " + draw);
                paintPanel.repaint();
            }
        });
        paintPanel = new JPanel() {
            double theta = Math.toRadians(25);
            int n = 4;

            @Override
            protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                if (draw) {
                    for(int i = 0; i < n; i++) {
                        int x1 = 50 + i*25;
                        int y1 = 50 + i*25;
                        int x2 = (int)(x1 + 100*Math.cos(theta));
                        int y2 = (int)(y1 + 100*Math.sin(theta));
                        g.drawLine(x1, y1, x2, y2);
                    }
                }
            }
        };
        System.out.println("Default layout manager for JFrame: " +
                            getLayout().getClass().getName());
        BorderLayout bl = new BorderLayout();
        bl.addLayoutComponent(jb, BorderLayout.NORTH);
        bl.addLayoutComponent(paintPanel, BorderLayout.CENTER);
        getContentPane().add(jb);
        getContentPane().add(paintPanel);
        setLayout(bl);
        paintPanel.setPreferredSize(new Dimension(500, 500));
        jb.setPreferredSize(new Dimension(50, 100));

        pack();
    }

    public static void main(String[] args) {
        MainLine m = new MainLine();
        m.setVisible(true);
    }
}

[janes]

thank you very very much, and how would I do if I wanted the segments stacked one after another. So that one followed after another. Thanks:)

[hardwired]

Play with the code inside the if statement block:

    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
            if (draw) {
                ... here ...
            }
        }

You have to experiment, imagine, try different things to get what you want.
Graphics is hands–on, imaginative work.

[janes]

ok thanks, i´ll try it :)

[abhiram naidu]

what do u mean by contentpane?

[PhQ]

what do u mean by contentpane?

I think it is a panel that holds the content.