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POWhy is this code not drawing a line?
 

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  1. POWhy is this code not drawing a line?
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    <p>I am not sure why my code is not working but it is driving me crazy.</p> <p>This is my class that should draw the button and creates the area to draw on:</p> <p>The second set of code is the driver program I need to make 4 canvas's that when I make two mouse clicks it draws a line between the two clicks and then repaints if I try and click on a canvas again.</p> <p>I get the following errors: error: invalid method declaration; return type required addMouseListener(this); ^ error: illegal start of type addMouseListener(this); ^</p> <pre><code>public class Scribble extends JPanel implements MouseListener { addMouseListener(this); int x, x1, y, y1; boolean flag = false; protected void paintComponent(Graphics g) { super.paintComponent(g); g.drawLine(x, y, x1, y1); } public void mouseReleased(MouseEvent e) { if (!flag){ x = e.getX(); y = e.getY(); flag = true; } else{ x1 = e.getX(); y1 = e.getY(); flag = false; repaint(); } } public void mouseExited(MouseEvent e){} public void mouseClicked(MouseEvent e){} public void mousePressed(MouseEvent e){} public void mouseMoved(MouseEvent e){} public void mouseEntered(MouseEvent e){} } public class Lab8Draw extends JFrame{ public Lab8Draw(){ Color c = new Color(100, 10, 200); setTitle("Lab 8 - Application #1"); setLayout(new GridLayout(2,2)); Scribble s = new Scribble(); s.setBackground(Color.WHITE); add(s); Scribble s1 = new Scribble(); s1.setBackground(Color.RED); add(s1); Scribble s2 = new Scribble(); s2.setBackground(c); add(s2); Scribble s3 = new Scribble(); s.setBackground(Color.BLUE); add(s3); } public static void main (String[] args){ Lab8Draw frame = new Lab8Draw(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setSize(800, 800); frame.setVisible(true); } } </code></pre>
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