displayable1.java

MIDP不支持小数。 所以画抛物线时只在模拟画了。 本代码就是模拟一个子弹飞行轨迹。

package paowuxian;

import javax.microedition.lcdui.*;
import java.io.*;
import java.util.Hashtable;
/**
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2005</p>
 * <p>Company: </p>
 * @author not attributable
 * @version 1.0
 */

public class Displayable1 extends Canvas implements CommandListener ,Runnable{

  private Image imgWu=null;
  private  int x,y;
  private boolean bFire=false;
  Thread thisThread;
   // public Hashtable angleValue;
//public int tempAngle;
//public int tempValue;
    private int angle=45;
    private int v0=10;
    private int windSpeed=0;//300000;
    private int vx,vy;

private boolean bShowline=true;
    private int t,tTemp;

  public Displayable1() {
    Resource.loadAngleValue();
    try {
      imgWu = Image.createImage("/images/paodan.png");

y =getHeight()-imgWu.getHeight();
     // x=getWidth()/2;
    }
    catch (IOException ex) {
    }
thisThread=new Thread(this);
    thisThread.start();

    try {
      jbInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }

  private void jbInit() throws Exception {
    // Set up this Displayable to listen to command events
    setCommandListener(this);
    // add the Exit command
    addCommand(new Command("Exit", Command.EXIT, 1));
  }

  public void commandAction(Command command, Displayable displayable) {
    /** @todo Add command handling code */
    if (command.getCommandType() == Command.EXIT) {
// stop the MIDlet
      MIDlet1.quitApp();
    }
  }

  private void gameRun(){
    if(bFire){
      x= (vx+windSpeed )*t /100000; ;
      int pianyi=(t*400000);
      if(vy==0){
        pianyi=0;
      }else if(vy<0){
        pianyi=280000*t;
      }
      y=(100000*(getHeight()-imgWu.getHeight())-(vy*t-100000*t*t+pianyi))/100000;
     // bFire=false;
    }

    repaint();
  }



  protected void paint(Graphics g) {
    g.setColor(0xffffffff);
    g.fillRect(50,10,80,40);
    if(bShowline){
      g.setColor(0xffffffff);
    g.fillRect(0,0,getWidth(),getHeight());
    }
    g.setColor(0x0000ff);
    g.drawString("角度"+angle+"(按8/2键调整)",50,0,0);
     g.drawString("力度"+v0+"(按1)",50,10,0);
      g.drawString("是否留下轨迹"+(bShowline?" 否":" 是")+"(按3)",50,20,0);
      g.drawString("风力"+windSpeed/100000+"(按7/9)",50,30,0);
    g.drawImage(imgWu,x,y,0);
  }
   public   void run(){
    while (true){
      try {
        thisThread.sleep(10);
        if(bFire){
          tTemp++;
          if (tTemp >2) {
            t+=1;
            tTemp = 0;
          }

          if(y>getHeight()||x>getWidth()){
            x=0;
            y=getHeight()-imgWu.getHeight();
            bFire=false;
            vx=0;vy=0;
            t=0;
            v0=10;
          }
        }
      }
      catch (InterruptedException ex) {
      }
      gameRun();


    }
  }

  /**
   * keyPressed
   *
   * @param keyCode int
   * @todo Implement this javax.microedition.lcdui.Canvas method
   */
  protected void keyPressed(int keyCode) {
    if(keyCode==KEY_NUM5){
      bFire=true;
      vx=Resource.getCosAngleValue(angle)*v0;
      vy=Resource.getSinAngleValue(angle)*v0;
    }else if(keyCode==KEY_NUM8){
      if(angle>0){
        angle -= 3;
      }
    }
    else if(keyCode==KEY_NUM2){
      if(angle<90){
        angle += 3;
      }

    }else if(keyCode==KEY_NUM1){
    v0++;
  }else if(keyCode==KEY_NUM3){
    bShowline=!bShowline;
  }else if(keyCode==KEY_NUM7){
    windSpeed+=100000;
  }else if(keyCode==KEY_NUM9){
    windSpeed-=100000;
  }





  }



}