/** * 判斷是否開啟了自動亮度調節 * * @param aContext * @return */public static boolean isAutoBrightness(ContentResolver aContentResolver) {  boolean automicBrightness = false;  try {    automicBrightness = Settings.System.getInt(aContentResolver,        Settings.System.SCREEN_BRIGHTNESS_MODE) == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC;  } catch (SettingNotFoundException e) {    e.printStackTrace();  }  return automicBrightness;}/** * 獲取屏幕的亮度 * * @param activity * @return */public static int getScreenBrightness(Activity activity) {  int nowBrightnessValue = 0;  ContentResolver resolver = activity.getContentResolver();  try {    nowBrightnessValue = android.provider.Settings.System.getInt(        resolver, Settings.System.SCREEN_BRIGHTNESS);  } catch (Exception e) {    e.printStackTrace();  }  return nowBrightnessValue;}/** * 設置亮度 * * @param activity * @param brightness */public static void setBrightness(Activity activity, int brightness) {  // Settings.System.putInt(activity.getContentResolver(),  // Settings.System.SCREEN_BRIGHTNESS_MODE,  // Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);  WindowManager.LayoutParams lp = activity.getWindow().getAttributes();  lp.screenBrightness = Float.valueOf(brightness) * (1f / 255f);  activity.getWindow().setAttributes(lp);}/** * 停止自動亮度調節 * * @param activity */public static void stopAutoBrightness(Activity activity) {  Settings.System.putInt(activity.getContentResolver(),      Settings.System.SCREEN_BRIGHTNESS,      Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);}/** * 開啟亮度自動調節 * * @param activity */public static void startAutoBrightness(Activity activity) {  Settings.System.putInt(activity.getContentResolver(),      Settings.System.SCREEN_BRIGHTNESS_MODE,      Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC);}/** * 保存亮度設置狀態 * * @param resolver * @param brightness */public static void saveBrightness(ContentResolver resolver, int brightness) {  Uri uri = android.provider.Settings.System      .getUriFor("screen_brightness");  android.provider.Settings.System.putInt(resolver, "screen_brightness",      brightness);  resolver.notifyChange(uri, null);}

sSeekBar = (SeekBar) findViewById(R.id.seek_bar);sSeekBar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {  @Override  public void onStopTrackingTouch(SeekBar seekBar) {    // TODO Auto-generated method stub  }  @Override  public void onStartTrackingTouch(SeekBar seekBar) {  }  @Override  public void onProgressChanged(SeekBar seekBar, int progress,      boolean fromUser) {    if (progress < 10) {    } else {      setBrightness(Test2Activity.this, progress);    }  }});//獲取當前亮度的位置int a =getScreenBrightness(this);sSeekBar.setProgress(a);

<SeekBar  android:id="@+id/seek_bar"  android:layout_width="200dp"  android:layout_height="wrap_content"  android:layout_alignParentBottom="true"  android:max="255"  android:maxHeight="8dp"  android:minHeight="8dp"  android:paddingBottom="5dp"  android:paddingLeft="13dp"  android:paddingRight="13dp"  android:progress="0"   />