移动

public class Move extends Activity
{
  /*图片的宽度*/
  private int intWidth;
  
  /*图片的高度*/
  private int intHeight;
  
  /*图片的X坐标*/
  private int intButtonX;
  
  /*图片的Y坐标*/
  private int intButtonY;
  
  /* 存储屏幕的分辨率 */
  private int intScreenX, intScreenY;
  
  /* 按钮位移的平移量 */
  private int intShift = 20;
  
  /*运行速度(数值越大，速度越小)*/
  private int speen = 1000;
  /*图片*/
  private ImageView myImage;
  
  /*定时器*/
  Timer timer = new Timer(true);
  
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState)
  {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    
    myImage = (ImageView)findViewById(R.id.myImage);
    
    DisplayMetrics dm = new DisplayMetrics(); 
    getWindowManager().getDefaultDisplay().getMetrics(dm);
    
    /* 取得屏幕解析像素 */
    intScreenX = dm.widthPixels;
    intScreenY = dm.heightPixels;
    
    /* 定义按钮的宽x高 */
    intWidth = 20;
    intHeight = 20;
    
    /* 初始化按钮位置居中 */
    RestoreButton();
    
    /* 当点击按钮，还原初始位置 */
    myImage.setOnClickListener(new Button.OnClickListener()
    {
      public void onClick(View v)
      {
        // TODO Auto-generated method stub
        RestoreButton();
      }
    });
  }

  private int flag = 0;
  TimerTask task = new TimerTask(){
    public void run(){
      Message message = new Message();
      message.what = flag;
      handler.sendMessage(message);
//      MoveButtonUp();
    }
  };
  
  Handler handler = new Handler()
  {
    public void handleMessage(Message msg)
    {
      if (intButtonY - intShift <= 0)
      {
        setTitle("game over " + flag);
      } else
      {
        switch (msg.what)
        {
          case 1:
            MoveButtonUp();
            break;
          case 2:
            MoveButtonDown();
            break;
          case 3:
            MoveButtonLeft();
            break;
          case 4:
            MoveButtonRight();
            break;
        }
        
      }

      super.handleMessage(msg);
    }
  };
  
  @Override
  public boolean onKeyDown(int keyCode, KeyEvent event)
  {
    // TODO Auto-generated method stub
    switch(keyCode)
    {
      /* 中间按键 */
      case KeyEvent.KEYCODE_DPAD_CENTER:
        /* keyCode=23 */
        RestoreButton();
        break;
      /* 上按键 */
      case KeyEvent.KEYCODE_DPAD_UP:
        /* keyCode=19 */
        if(flag!=2){
          MoveButtonUp();
        }
        break;
      /* 下按键 */
      case KeyEvent.KEYCODE_DPAD_DOWN:
        /* keyCode=20 */
        if(flag!=1){
          MoveButtonDown();
        }
        break;
      /* 左按键 */
      case KeyEvent.KEYCODE_DPAD_LEFT:
        /* keyCode=21 */
        if(flag!=4){
          MoveButtonLeft();
        }
        break;
      /* 右按键 */
      case KeyEvent.KEYCODE_DPAD_RIGHT:
        /* keyCode=22 */
        if(flag!=3){
          MoveButtonRight();
        }
        break;
    }
    return super.onKeyDown(keyCode, event);
  }
  
  /* 还原按钮位置的事件处理 */
  public void RestoreButton()
  {
    intButtonX = ((intScreenX-intWidth)/2);
    intButtonY = ((intScreenY-intHeight)/2);
    mMakeTextToast
    (
      "("+
      Integer.toString(intButtonX)+
      ","+
      Integer.toString(intButtonY)+")",true
    );
    
    /* 以setLayoutParams方法，重新安排Layout上的位置 */
    myImage.setLayoutParams
    (
      new AbsoluteLayout.LayoutParams
      (intWidth,intHeight,intButtonX,intButtonY)
    );
  }
  
  /* 点击DPAD上按键时事件处理 */
  public void MoveButtonUp()
  {
    intButtonY = intButtonY-intShift;
    /* 预防按钮到达下边界时的处理 */
    if(intButtonY<0)
    {
      intButtonY = 0;
    }
    myImage.setLayoutParams
    (
      new AbsoluteLayout.LayoutParams
      (intWidth,intHeight,intButtonX,intButtonY)
    );
    if (flag == 0)
    {
      flag = 1;
      timer.schedule(task, 0, speen);
    }
    flag = 1;
  }
  
  /* 点击DPAD下按键时事件处理 */
  public void MoveButtonDown()
  {
    intButtonY = intButtonY+intShift;
    /* 预防按钮到达下边界时的处理 */
    if(intButtonY>(intScreenY-70))
    {
      intButtonY = intScreenY-70;
    }
//    mMakeTextToast
//    (
//      "("+Integer.toString(intButtonY)+","+Integer.toString(intScreenY-intHeight)+")",true
//    );
    myImage.setLayoutParams
    (
      new AbsoluteLayout.LayoutParams
      (intWidth,intHeight,intButtonX,intButtonY)
    );
    if (flag == 0)
    {
      flag = 2;
      timer.schedule(task, 0, speen);
    }
    flag = 2;
  }
  
  /* 点击DPAD左按键时事件处理 */
  public void MoveButtonLeft()
  {
    intButtonX = intButtonX-intShift;
    /* 预防按钮到达左边界时的处理 */
    if(intButtonX<0)
    {
      intButtonX = 0;
    }
    myImage.setLayoutParams
    (
      new AbsoluteLayout.LayoutParams
      (intWidth,intHeight,intButtonX,intButtonY)
    );
    if (flag == 0)
    {
      flag = 3;
      timer.schedule(task, 0, speen);
    }
    flag = 3;
  }
  
  /* 点击DPAD右按键时事件处理 */
  public void MoveButtonRight()
  {
    intButtonX = intButtonX+intShift;
    /* 预防按钮到达右边界时的处理 */
    if(intButtonX>(intScreenX-intWidth))
    {
      intButtonX = intScreenX-intWidth;
    }
    myImage.setLayoutParams
    (
      new AbsoluteLayout.LayoutParams
      (intWidth,intHeight,intButtonX,intButtonY)
    );
    if (flag == 0)
    {
      flag = 4;
      timer.schedule(task, 0, speen);
    }
    flag = 4;
  }
  
  public void mMakeTextToast(String str, boolean isLong)
  {
    if(isLong==true)
    {
      Toast.makeText(Move.this, str, Toast.LENGTH_LONG).show();
    }
    else
    {
      Toast.makeText(Move.this, str, Toast.LENGTH_SHORT).show();
    }
  }
}


main.xml
<?xml version="1.0" encoding="utf-8"?>
<AbsoluteLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:background="@drawable/white"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  >
  <ImageView
        android:id="@+id/myImage"
        android:src="@drawable/a"
        android:layout_width="10px"
    android:layout_height="10px"
  />
</AbsoluteLayout>