Android开发实现调节屏幕亮度功能

<uses-permission android:name="android.permission.CHANGE_CONFIGURATION"/><uses-permission android:name="android.permission.WRITE_SETTINGS"/>

/*** 判断是否开启了自动亮度调节*/public static boolean isAutoBrightness(Context context) {  ContentResolver resolver = context.getContentResolver();  boolean automicBrightness = false;  try {   automicBrightness = Settings.System.getInt(resolver,     Settings.System.SCREEN_BRIGHTNESS_MODE) == Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC;  } catch (Settings.SettingNotFoundException e) {   e.printStackTrace();  }  return automicBrightness;}/*** 获取屏幕的亮度*/public static int getScreenBrightness(Context context) {  int nowBrightnessValue = 0;  ContentResolver resolver = context.getContentResolver();  try {   nowBrightnessValue = android.provider.Settings.System.getInt(resolver, Settings.System.SCREEN_BRIGHTNESS);  } catch (Exception e) {   e.printStackTrace();  }  return nowBrightnessValue;}/*** 设置当前Activity显示时的亮度* 屏幕亮度最大数值一般为255，各款手机有所不同* screenBrightness 的取值范围在[0,1]之间*/public static void setBrightness(Activity activity, int brightness) {  WindowManager.LayoutParams lp = activity.getWindow().getAttributes();  lp.screenBrightness = Float.valueOf(brightness) * (1f / 255f);  activity.getWindow().setAttributes(lp);}/*** 开启关闭自动亮度调节*/public static boolean autoBrightness(Context activity, boolean flag) {  int value = 0;  if (flag) {   value = Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC; //开启  } else {   value = Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL;//关闭  }  return Settings.System.putInt(activity.getContentResolver(),    Settings.System.SCREEN_BRIGHTNESS_MODE,    value);}/*** 保存亮度设置状态，退出app也能保持设置状态*/public static void saveBrightness(Context context, int brightness) {  ContentResolver resolver = context.getContentResolver();  Uri uri = android.provider.Settings.System.getUriFor(Settings.System.SCREEN_BRIGHTNESS);  android.provider.Settings.System.putInt(resolver, Settings.System.SCREEN_BRIGHTNESS, brightness);  resolver.notifyChange(uri, null);}