android brightness control

package com.smarttpapers.reader.dialog;



import android.app.Activity;

import android.app.Dialog;

import android.content.ContentResolver;

import android.content.Context;

import android.net.Uri;

import android.provider.Settings;

import android.provider.Settings.SettingNotFoundException;

import android.view.WindowManager;

import android.widget.SeekBar;

import android.widget.SeekBar.OnSeekBarChangeListener;



import com.smarttpapers.reader.R;



public class DialogBrightness extends Dialog{



    private int brightnessValue;

    private boolean isAuto;

    public DialogBrightness(final Context context, int theme) {

        super(context, theme);

        setContentView(R.layout.popup_brightness);

        setTitle("Brightness");

        setCanceledOnTouchOutside(true);

        final SeekBar brightness = (SeekBar)findViewById(R.id.page_bightness);

        int nowBrightnessValue = 0;

        final ContentResolver resolver = ((Activity)context).getContentResolver();

        try {

            nowBrightnessValue = android.provider.Settings.System.getInt(

                    resolver, Settings.System.SCREEN_BRIGHTNESS);

        } catch (Exception e) {

            e.printStackTrace();

        }

        brightness.setProgress(nowBrightnessValue);

        isAuto=isAutoBrightness(resolver);

        if(isAuto){

            stopAutoBrightness((Activity)context);

        }

        brightness.setOnSeekBarChangeListener(

                new OnSeekBarChangeListener() {

            @Override

            public void onStopTrackingTouch(SeekBar seekBar) {

                saveBrightness(resolver, brightnessValue);

            }

            

            @Override

            public void onStartTrackingTouch(SeekBar seekBar) {}

            

            @Override

            public void onProgressChanged(SeekBar seekBar, int progress,

                    boolean fromUser) {

                brightnessValue=progress+10;

                setBrightness((Activity)context, brightnessValue);

            }

        });

    }

    public 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;

    }

     public void setBrightness(Activity activity, int bright) {

            WindowManager.LayoutParams lp = activity.getWindow().getAttributes();

            lp.screenBrightness = Float.valueOf(bright) * (1f / 255f);

            activity.getWindow().setAttributes(lp);

        }

    public void startAutoBrightness(Activity activity) {

        Settings.System.putInt(activity.getContentResolver(),

                Settings.System.SCREEN_BRIGHTNESS_MODE,

                Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC);

    }

    public void stopAutoBrightness(Activity activity) {

        Settings.System.putInt(activity.getContentResolver(),

                Settings.System.SCREEN_BRIGHTNESS_MODE,

                Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL);

    }

    public void saveBrightness(ContentResolver resolver, int bright) {

        Uri uri = android.provider.Settings.System

                .getUriFor("screen_brightness");

        android.provider.Settings.System.putInt(resolver, "screen_brightness",

                bright);

        resolver.notifyChange(uri, null);

    }

}