item.java

斜45度游戏范例

package isoj2me;

import java.util.Hashtable;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;

/**
 * <p>Title: isoj2me: J2ME Isometric Engine</p>
 * <p>Description: An engine/framework for isometric games (like japanese RPGs) for mobile devices supporting J2ME (MIDP 1.0). This engine will manage maps, objects and characters. Visit http://sourceforge.net/projects/isoj2me</p>
 * <p>Copyright: Copyright (c) 2004</p>
 * <p>License: Lesser GPL (http://www.gnu.org)</p>
 * <p>Company: Mondonerd.com</p>
 * @author Massimo Maria Avvisati
 * @version 0.2
 */

public class Item {
  public boolean isMoving = false;
  public String name = "";
  public int x = 0;
  public int y = 0;
  public int z = 0;

  private int frame = 0;
  private Hashtable actions = new Hashtable(6);
  private String currentAction = null;

  private Hashtable frames = new Hashtable();

  public Item() {
  }

  /**
   * Create a new Item.
   * @param name Name/code of the Item
   */
  public Item(String name) {
    this.name = name;
  }

  /**
   * Create a new Item
   * @param name Name or code of the Item
   * @param x x on the map
   * @param y y on the map
   * @param z layer on the map
   */

  public Item(String name, int x, int y, int z) {
    this.name = name;
    this.x = x;
    this.y = y;
    this.z = z;
  }

  /**
   * This draw the Item at given coordinates on given Graphics. This method also change the current frame (if more than one) for the current action.
   * @param x x
   * @param y y
   * @param g given Graphics where to paint the Item
   */

  public void draw(int x, int y, Graphics g) {
    if (currentAction != null && actions.containsKey(currentAction)) {
      String tempFrame = "";

      if (frame > Integer.parseInt(actions.get(currentAction).toString())) {
	frame = 0;
      }
      if (frame > 0) {
	tempFrame = frame + "";
      }
      Image temp_image = Utility.loadTile(currentAction + tempFrame, frames);
      //int temp_x = x + (width - temp_image.getWidth()) / 2;

      g.drawImage(temp_image, x, y - temp_image.getHeight(),
		  g.TOP | g.LEFT);

      changeFrame();
    }
  }

  /**
   * Store an action into this Item action list.
   * @param action basic string used to load frames
   * @param frames number of frames for this action
   */

  public void putAction(String action, int frames) {
    actions.put(action, frames + "");
  }

  /**
   * This return the name that identify the action that is performed in this moment by the Item
   * @return basic string for this action
   */

  public String getCurrentAction() {
    return currentAction;
  }

  /**
   * Calculate the current frame and return the associated Image object
   * @return current Image used
   */

  public Image getCurrentImage() {
    Image temp_image = null;
    if (currentAction != null && actions.containsKey(currentAction)) {
      String tempFrame = "";

      if (frame > Integer.parseInt(actions.get(currentAction).toString())) {
	frame = 0;
      }
      if (frame > 0) {
	tempFrame = frame + "";
      }
      temp_image = Utility.loadTile(currentAction + tempFrame, frames);
    }

    return temp_image;
  }

  /**
   * Set the current action for this Item. The action have to be already in the actions list
   * @param action name of the action to perform
   */

  public void setCurrentAction(String action) {
    if (actions.containsKey(action)) {
      currentAction = action;
    }
  }

  private void changeFrame() {
    if (actions.containsKey(currentAction)) {
      int numberOfFrames = Integer.parseInt(actions.get(currentAction).toString());
      frame++;
      if (frame > numberOfFrames) {
	frame = 0;
      }
    }
    else {
      frame = 0;
    }
  }

  /**
   * Return the name of the Item
   * @return name of the Item
   */

  public String toString() {
    return this.name;
  }

}