android 设置系统屏幕亮度

  /**
     * 获得当前屏幕亮度的模式
     * SCREEN_BRIGHTNESS_MODE_AUTOMATIC=1 为自动调节屏幕亮度
     * SCREEN_BRIGHTNESS_MODE_MANUAL=0 为手动调节屏幕亮度
     */
    private int getScreenMode() {
        int screenMode = 0;
        try {
            screenMode = Settings.System.getInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS_MODE);
        } catch (Exception localException) {

        }
        return screenMode;
    }

    /**
     * 获得当前屏幕亮度值 0--255
     */
    private int getScreenBrightness() {
        int screenBrightness = 255;
        try {
            screenBrightness = Settings.System.getInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS);
        } catch (Exception localException) {

        }
        return screenBrightness;
    }

    /**
     * 设置当前屏幕亮度的模式
     * SCREEN_BRIGHTNESS_MODE_AUTOMATIC=1 为自动调节屏幕亮度
     * SCREEN_BRIGHTNESS_MODE_MANUAL=0 为手动调节屏幕亮度
     */
    private void setScreenMode(int paramInt) {
        try {
            Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS_MODE, paramInt);
        } catch (Exception localException) {
            localException.printStackTrace();
        }
    }

    /**
     * 设置当前屏幕亮度值 0--255
     */
    private void saveScreenBrightness(int paramInt) {
        try {
            Settings.System.putInt(getContentResolver(), Settings.System.SCREEN_BRIGHTNESS, paramInt);
        } catch (Exception localException) {
            localException.printStackTrace();
        }
    }

    /**
     * 保存当前的屏幕亮度值，并使之生效
     */
    private void setScreenBrightness(int paramInt) {
        Window localWindow = getWindow();
        WindowManager.LayoutParams localLayoutParams = localWindow.getAttributes();
        float f = paramInt / 255.0F;
        localLayoutParams.screenBrightness = f;
        localWindow.setAttributes(localLayoutParams);
    }