clickable line

[Ravi Gupta]

hi all

I would like to know if there is a way to make a line that connects two buttons clickable? i.e. on being clicked the line should change colour.

[Craig Wood]

import java.awt.*;
import java.awt.event.*;
import java.awt.geom.Line2D;
import javax.swing.*;
public class Clickables extends JPanel {
Point selection = new Point(-1,-1);
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
Component[] c = getComponents();
for(int j = 0; j < c.length; j++) {
Rectangle r = c[j].getBounds();
double x1 = r.getCenterX();
double y1 = r.getCenterY();
for(int k = j+1; k < c.length; k++) {
r = c[k].getBounds();
double x2 = r.getCenterX();
double y2 = r.getCenterY();
Color color = (j==selection.x && k==selection.y) ? Color.red
: Color.blue;
g2.setPaint(color);
g2.draw(new Line2D.Double(x1, y1, x2, y2));
}
}
}
public static void main(String[] args) {
Clickables test = new Clickables();
test.setLayout(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.weightx = 1.0;
test.add(new JButton("Button 1"), gbc);
test.add(new JButton("Button 2"), gbc);
test.addMouseListener(test.ml);
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.getContentPane().add(test);
f.setSize(400,200);
f.setLocation(200,200);
f.setVisible(true);
}
private MouseListener ml = new MouseAdapter() {
final int S = 6;
Rectangle sensor = new Rectangle(S,S);
public void mousePressed(MouseEvent e) {
Point p = e.getPoint();
sensor.setFrameFromCenter(p.x, p.y, p.x+S/2, p.y+S/2);
Container source = (Container)e.getComponent();
Component[] c = source.getComponents();
for(int j = 0; j < c.length; j++) {
Rectangle r = c[j].getBounds();
double x1 = r.getCenterX();
double y1 = r.getCenterY();
for(int k = j+1; k < c.length; k++) {
r = c[k].getBounds();
double x2 = r.getCenterX();
double y2 = r.getCenterY();
if(new Line2D.Double(x1,y1,x2,y2).intersects(sensor)) {
if(selection.x == j && selection.y == k)
selection.setLocation(-1,-1); // toggle off
else
selection.setLocation(j, k); // set values
source.repaint();
return;
}
}
}
}
};
}