Creating triangles using the Polygon class problem???

[Luong Vuong]

Hi i am trying to create a triangle using the Polygon class. Eventually the program should allow the user to click on the screen and triangles should appear. I the programmer decide the size of the triangle.

    
private int[]x = new int[3];
private int[]y = new int[3];
private int n;  // count of points
 
public void paint(Graphics gc)
{
if(m_bMouse)
 {
    gc.setColor(Color.green); 
           gc.fillPolygon(myTri.x, myTri.y, n);
         }
}

When i try to compile i get the following error message
Cannot find symbol variable x
---- find symbol variable y.

Please help, urgent

[Ernest Friedman-Hill]

Hi,

Welcome to JavaRanch!

We have a strict policy on display names, which must be a real first and last name with a space between.

Please go here and fix your display name up, pronto. Thanks, pardner!

[Luong Vuong]

sorry about that.

[Ernest Friedman-Hill]

Thanks!

OK, so what is "myTri" declared as? If it's a java.awt.Polygon, there is an xpoints and a ypoints, but no x or y. But you've also declared your own x and y variables, so I'm not quite sure what you're doing; maybe you should show us more code.

[Luong Vuong]

Here is the full code:

    
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
 
public class DrawTri
 {
 
 public static void main(String args[])
 {
 new MainWindow();
 }
 }
 class MainWindow extends Frame
 {
 private boolean m_bMouse;
 
 private int m_nTrianglesToDraw;
 private int m_nTrianglesDrawn;
 private int m_nWndWidth;
 private int m_nWndHeight;
 
 private int[]x = new int[3];
private int[]y = new int[3];
private int n;  // count of points

private Polygon[] m_polyTriangleArr;
 
 MainWindow()
 {
 setTitle("Drawing Triangles");
 m_bMouse = false;
 m_nTrianglesToDraw = 0;
 m_nTrianglesDrawn = 0;
 m_WndFont = new Font ("Helvetica", Font.BOLD, 20);
 
 addMouseListener(new MouseCatcher() );
setVisible(true);
 }
 
class MouseCatcher extends MouseAdapter
  {
  
  public void mousePressed(MouseEvent evt)
  {
  Point ptMouse = new Point();
  ptMouse = evt.getPoint();
  
  if(m_nTrianglesDrawn < m_nTrianglesToDraw)
  {
  
    //private Polygon[] m_polyTriangleArr;
    
  
  m_polyTriangleArr[m_nTrianglesDrawn] 
  = new Polygon( x, y, n);
  
  //m_polyTriangleArr[m_nTrianglesDrawn] 
  //= new Polygon( ptMouse, ptMouse, int);
  
  m_nTrianglesDrawn++;
  m_bMouse = true;
  repaint();
  }
                }
 
public void paint(Graphics gc)
 {
                 x[0]=100;  x[1]=150;  x[2]=50;
 y[0]=100;  y[1]=150;  y[2]=150;
n = 3;
 Polygon myTri = new Polygon(x, y, n);  // a triangle
 
 
 if(m_bMouse)
 {
 gc.setColor(Color.green);
 
 for( int i = 0; i < m_nTrianglesDrawn; i++)
 {
 gc.fillPolygon(x, y, n);
 }
 }
           }

Hope that this code helps guys

[Ernest Friedman-Hill]

I'm afraid there may be some organizational problems that are preventing you from communicating effectively with us. Your previous code snippet is not a subset of this larger code -- in fact, it differs in the crucial aspect of how "x" and "y" are used. And aside from a few missing close-braces at the end, and the use of the undefined variable m_WndFont, this code compiles fine.