如何在Android应用层中制作一个LED指示灯效果

public class LEDActivity extends Activity implements View.OnClickListener {private static final String TAG = "LED";Button mLedTest;int mLedStatus = 0;private final int mLedColorRed = 0xFFFF0000;final byte[] LIGHT_ON = { '2', '5', '5' };final byte[] LIGHT_OFF = { '0' };private final int RED = 0;private int color = RED;String RED_LED_DEV = " /sys/class/leds/torch/brightness";public void onCreate(Bundle paramBundle) {  super.onCreate(paramBundle);  setContentView(R.layout.led_test);  mLedTest = ((Button)findViewById(R.id.ledcolor));  mLedTest.setOnClickListener(this); //  setledlightcolor(color); //  mLedTest.setTextColor(mLedColorRed); //  mLedTest.setText("RED");  //  mLedStatus = 1; } public void onClick(View v) { Log.d("LEDActivity", "---onClick---mLedStatus=" + mLedStatus); switch (v.getId()) { case R.id.ledcolor: if(mLedStatus == 0) { mLedTest.setText("开"); mLedStatus = 1 }else if(mLedStatus == 1) {   mLedTest.setText("关");   mLedStatus = 0; } break; } } @Overridepublic void finish() {  setledlightcolor(-1);  super.finish();}private void setledlightcolor(int color) {  logd("set:" + color);  boolean red = false;  switch (color) {  case RED:    red = true;    break;  default:    break;  }  try {    FileOutputStream foRed = new FileOutputStream(RED_LED_DEV);    Log.d(TAG, "foRed" + foRed);    fRed.write(red ? LIGHT_ON : LIGHT_OFF);    fRed.close();  } catch (Exception e) {    loge(e);  }}void logd(Object d) {  Log.d(TAG, "" + d);}void loge(Object e) {  Log.e(TAG, "" + e);}}