boardpanel.java

ParallelConnectFour是一个java小游戏

package edu.rit.cs.mlr5773.connectfour;

import java.awt.*;
import java.util.*;

/**
 * GUI Object to view a Connect 4 Board
 *
 * @author Mark Roth
 */
public class BoardPanel extends Panel implements Observer {

  /** The Board we are observing */
  private Board board;

  /* The color to represent each player by: */
  private static final Color[] playerColor = 
    { Color.lightGray, Color.red, Color.black };

  /**
   * Creates a new Board Panel, and adds this object as an observer to 
   * the game board.
   */
  public BoardPanel(Board board){
    this.board = board;
    board.addObserver( this );
  }  

  /**
   * Draws a single piece on the board
   */
  private void drawPiece( Graphics g, int x, int y, Color c ) {
    g.setColor( c );
    g.fillOval( x*50 + 10, (5-y)*50 + 10, 50 - 10, 50 - 10);

    g.setColor( Color.white );
    g.drawOval( x*50 + 10-1, (5-y)*50 + 10-1, 50 - 10, 50 - 10);
    g.setColor( new Color( 128, 128, 0 ) );
    g.drawOval( x*50 + 10, (5-y)*50 + 10, 50 - 10, 50 - 10);
  }  

  /**
   * Returns the desired size of the panel
   */
  private Dimension getGridSize() {
    return new Dimension( 7*50 + 10, 6*50 + 10);
  }  

  /** 
   * Gets the maximum size of this object
   */
  public Dimension getMaximumSize() {
    return getGridSize();
  }  

  /** 
   * Gets the minimum size of this object
   */
  public Dimension getMinimumSize() {
    return getGridSize();
  }  

  /** 
   * Gets the preferred size of this object
   */
  public Dimension getPreferredSize() {
    return getGridSize();
  }  

  /**
   * Draws this board to the given Graphics object
   */
  public void paint( Graphics g ) {
    int x, y;
    g.setColor( Color.yellow );
    g.fillRect( 0, 0, 7*50 + 10, 6*50 + 10 );
	
    for( y = 0; y < 6; y++ ) {
      for( x = 0; x < 7; x++ ) {
 	drawPiece( g, x, y, playerColor[board.getAt( x, y )] );
      }
    }
  }  

  /**
   * Incrementally draws this object
   */
  public void update( Observable source, Object hint ) {
    Point move = (Point)hint;
    Board board = (Board)source;
    int player = board.getAt( move.x, move.y );
    drawPiece( getGraphics(), move.x, move.y, playerColor[ player ] );
  }

}