Elevator Gui

Question

Hi guys. Can anyone help me with this. I cant seems to get my elevator working. I jus want it to get it moving only thats all. For now at least.
Here is my code.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
//The main class
public class Elevator_Simulation extends JFrame{
  public JLabel state; // display the state of the elevator
  private JLabel id;  //your name and group
  public ButtonPanel control= new ButtonPanel(); //the button control panel
  private Elevator elevator; // the elevator area
  private static final String myProperty = "Name: XXX Group: XXX";
  //constructor
  public Elevator_Simulation()
  // Create GUI
       setTitle("Elevator_Simulation");
       Container container = getContentPane();
  // Centralise my name & group
       id = new JLabel(myProperty);
       JPanel idPanel = new JPanel();
       idPanel.add(id);
       getContentPane().add(idPanel, BorderLayout.NORTH);
  // Add ButtonPanel
       JPanel buttonPanel=new JPanel();
       buttonPanel.add(control);
       getContentPane().add(control, BorderLayout.WEST);
  // Add state
       state=new JLabel("Up/Down");
       JPanel statePanel = new JPanel();
       statePanel.add(state);
       getContentPane().add(statePanel, BorderLayout.SOUTH);
  /* Add elevator
       JPanel elevatorPanel= new JPanel();
       elevatorPanel.add(elevator);
       getContentPane().add(elevatorPanel, BorderLayout.CENTER);
  // Main method
  public static void main(String[] args) {
  // Create a frame and display it
       Elevator_Simulation frame = new Elevator_Simulation();
       frame.setSize(500,500);
       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
       frame.getContentPane().add(new Elevator(frame));
  // GUI @ Middle Screen      
       Dimension  screenSize = Toolkit.getDefaultToolkit().getScreenSize();
          int screenWidth = screenSize.width;
          int screenHeight = screenSize.height;
          int x = (screenWidth - frame.getWidth())/2;
          int y = (screenHeight - frame.getHeight())/2;
          frame.setLocation(x,y);
          frame.setVisible(true);
} //the end of Elevator_Simulation class
//The ButtonPanel class receives and handles button pressing events
class ButtonPanel extends JPanel implements ActionListener {
  public JButton b[] = new JButton[8];  // 8 Buttons
  public boolean bp[] = new boolean[8]; // the state of each button, pressed or not
  //constructor
  public ButtonPanel() {
  //create GUI
      setLayout(new GridLayout(8,1));
  // Create 8 Floor Buttons and register listeners
          for (int i=1; i<=8; i++)
               b[8-i] = new JButton("F"+(8-(i-1)));
               b[8-i].setBackground(Color.blue);
               b[8-i].addActionListener(this);
               add(b[8-i]);
  public void actionPerformed(ActionEvent e) {
  //handle the button pressing events
       Toolkit.getDefaultToolkit().beep();
} //the end of ButtonPanel class
// The elevator class draws the elevator area and simulates elevator movement
class Elevator extends JPanel implements ActionListener{
  //Declaration of variables
  private Elevator_Simulation app; //the Elevator Simulation frame
  private boolean up; // the elevator is moving up or down
  private int width;  // Elevator width
  private int height; // Elevator height
  private int xco;     // The x coordinate of the elevator's upper left corner
  private int yco; // The y coordinate of the elevator's upper left corner
  private int dy0; // Moving interval
  private int topy; //the y coordinate of the top level
  private int bottomy; // the y coordinate of the bottom level
  private Timer tm; //the timer to drive the elevator movement
  //other variables to be used ...
  //constructor
  public Elevator(Elevator_Simulation app) {
  //necessary initialization
       Timer timer=new Timer(100,this);
       timer.start();
  // Paint elevator area
  public void paintComponent(Graphics g) {
  //obtain geometric values of components for drawing the elevator area
  //clear the painting canvas
  //start the Timer if not started elsewhere
  //draw horizontal lines and the elevator 
       width = getWidth()/8;
       height= getHeight()/8;
       bottomy = (height * 7)+ height;
       topy= 0;
       xco= (getWidth()/2)-(width/2);
       yco= (getHeight()/2)-(height/2);
       super.paintComponent(g); 
       // Create 8 Lines
       for (int i=0; i<=8; i++)
            g.setColor(Color.black);
            g.drawLine(0,(height*i),getWidth(), (height*i));
       if ( yco > getHeight())
            yco=bottomy;
      yco +=2;
      g.setColor(Color.gray);
      g.fillRect(xco, yco, width, height);
      g.setColor(Color.magenta);
      g.drawLine(xco+(width/2), yco, xco+(width/2), (yco+height));
  //Handle the timer events
  public void actionPerformed(ActionEvent e) {
  //loop if the elevator needs to be stopped for a while
  //adjust Y coordinate to simulate elevetor movement
  //change moving direction when hits the top and bottom
  //repaint the panel
       repaint();
  //update the state of the elevator
} //the end of Elevator classi think theres something wrong with the way i set my timer. I jus want it to move to the top(topy) then restart at the bottomy then move back up again. Greatly appreciate if someone could assist me.

Answer 1

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
//The main class
public class Elevator_Simulation extends JFrame{
  public JLabel state; // display the state of the elevator
  private JLabel id;  //your name and group
  public ButtonPanel control= new ButtonPanel(); //the button control panel
  private Elevator elevator; // the elevator area
  private static final String myProperty = "Name: Loh Khai Ping Group: SE2";
  //constructor
  public Elevator_Simulation()
  // Create GUI
       setTitle("Elevator_Simulation");
       Container container = getContentPane();
  // Centralise my name & group
       id = new JLabel(myProperty);
       JPanel idPanel = new JPanel();
       idPanel.add(id);
       getContentPane().add(idPanel, BorderLayout.NORTH);
  // Add ButtonPanel
       JPanel buttonPanel=new JPanel();
       buttonPanel.add(control);
       getContentPane().add(control, BorderLayout.WEST);
  // Add state
       state=new JLabel("Up/Down");
       JPanel statePanel = new JPanel();
       statePanel.add(state);
       getContentPane().add(statePanel, BorderLayout.SOUTH);
  /* Add elevator
       JPanel elevatorPanel= new JPanel();
       elevatorPanel.add(elevator);
       getContentPane().add(elevatorPanel, BorderLayout.CENTER);
  // Main method
  public static void main(String[] args) {
  // Create a frame and display it
       Elevator_Simulation frame = new Elevator_Simulation();
       frame.setSize(500,500);
       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
       frame.getContentPane().add(new Elevator(frame));
  // GUI @ Middle Screen      
       Dimension  screenSize = Toolkit.getDefaultToolkit().getScreenSize();
          int screenWidth = screenSize.width;
          int screenHeight = screenSize.height;
          int x = (screenWidth - frame.getWidth())/2;
          int y = (screenHeight - frame.getHeight())/2;
          frame.setLocation(x,y);
          frame.setVisible(true);
} //the end of Elevator_Simulation class
//The ButtonPanel class receives and handles button pressing events
class ButtonPanel extends JPanel implements ActionListener {
  public JButton b[] = new JButton[8];  // 8 Buttons
  public boolean bp[] = new boolean[8]; // the state of each button, pressed or not
  //constructor
  public ButtonPanel() {
  //create GUI
      setLayout(new GridLayout(8,1));
  // Create 8 Floor Buttons and register listeners
          for (int i=1; i<=8; i++)
               b[8-i] = new JButton("F"+(8-(i-1)));
               b[8-i].setBackground(Color.blue);
               b[8-i].addActionListener(this);
               add(b[8-i]);
  public void actionPerformed(ActionEvent e) {
  //handle the button pressing events
       Toolkit.getDefaultToolkit().beep();
} //the end of ButtonPanel class
// The elevator class draws the elevator area and simulates elevator movement
class Elevator extends JPanel implements ActionListener{
  //Declaration of variables
  private Elevator_Simulation app; //the Elevator Simulation frame
  private boolean up; // the elevator is moving up or down
  private int width;  // Elevator width
  private int height; // Elevator height
  private int xco;     // The x coordinate of the elevator's upper left corner
  private int yco; // The y coordinate of the elevator's upper left corner
  private int dy0; // Moving interval
  private int topy; //the y coordinate of the top level
  private int bottomy; // the y coordinate of the bottom level
  private Timer tm; //the timer to drive the elevator movement
  //other variables to be used ...
  //constructor
  public Elevator(Elevator_Simulation app) {
  //necessary initialization
       tm =new Timer(100,this);
       tm.start();
  // Paint elevator area
  public void paintComponent(Graphics g) {
  //obtain geometric values of components for drawing the elevator area
  //clear the painting canvas
  //start the Timer if not started elsewhere
  //draw horizontal lines and the elevator 
       width = getWidth()/8;
       height= getHeight()/8;
       bottomy = (height * 7);
       topy= 0;
       xco= (getWidth()/2)-(width/2);
       yco=  bottomy;
       super.paintComponent(g);
       // Create 8 Lines
       for (int i=0; i<=8; i++)
            g.setColor(Color.black);
            g.drawLine(0,(height*i),getWidth(), (height*i));
      g.setColor(Color.gray);
      g.fillRect(xco, yco, width, height);
      g.setColor(Color.magenta);
      g.drawLine(xco+(width/2), yco, xco+(width/2), (yco+height));
  //Handle the timer events
  public void actionPerformed(ActionEvent e) {
  //loop if the elevator needs to be stopped for a while
  //adjust Y coordinate to simulate elevetor movement
  //change moving direction when hits the top and bottom
  //repaint the panel
       yco +=2;
       xco +=2;
       /* if ( yco >= 0 )
            yco=bottomy;
      repaint();
  //update the state of the elevator
} //the end of Elevator class*Updated code.. It still cant move. Please assist.