showplane.java

j2me 小的子弹精灵,简单介绍sprite 的一个例子

package spriteplane;

import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.*;
import spritebullet.*;
public class ShowPlane
    extends GameCanvas
    implements CommandListener, Runnable {
  int scnW, scnH;
  Plane plane;
  Graphics g;
  Bullet bullets;
  public ShowPlane() {
    super(false);
    scnW = getWidth();
    scnH = getHeight();
    addCommand(new Command("Exit", Command.EXIT, 1));
    setCommandListener(this);
    g = this.getGraphics();
    plane = new Plane(g, scnW, scnH, 24, 24);
    bullets = new Bullet();
    Thread t = new Thread(this);
    t.start();
  }

  public void commandAction(Command command, Displayable displayable) {
    if (command.getCommandType() == Command.EXIT) {
      MainMIDlet.quitApp();
    }
  }

  public void KeyInput() {
    int key = this.getKeyStates();
    if ( (key & this.LEFT_PRESSED) != 0) {
      plane.moveLeft();
    }
    else if ( (key & this.RIGHT_PRESSED) != 0) {
      plane.moveRight();
    }
    if ( (key & this.UP_PRESSED) != 0) {
      plane.moveUp();
    }
    else if ( (key & this.DOWN_PRESSED) != 0) {
      plane.moveDown();
    }
    if ( (key & this.GAME_A_PRESSED) != 0) {
      plane.moveNS();
    }
    //开火
    if ( (key & this.FIRE_PRESSED) != 0) {
      bullets.addBullet(plane.x,plane.y,24);
    }
  }

  public void Clear() {
    g.setColor(255, 255, 255); //clear screen
    g.fillRect(0, 0, getWidth(), getHeight());
  }

  public void run() {
    while (true) {
      Clear();
      KeyInput();
      plane.DrawSelf();
      bullets.DrawSelf(g);
      bullets.Move();
      flushGraphics();
      try {
        Thread.sleep(30);
      }
      catch (Exception e) {}
      Clear();
    }
  }
}