[Blog] DIY Hue Lightbulb with Android Control

01.py

#!/usr/bin/python

import time
import RPi.GPIO as GPIO
from pubnub import Pubnub  

02.py

## Make your pin assignments
red_gpio   = 18
green_gpio = 23
blue_gpio  = 24

03.py

## Setup GPIO Board and Pins
GPIO.setmode(GPIO.BCM)    # BCM for GPIO numbering  
GPIO.setup(red_gpio,   GPIO.OUT)
GPIO.setup(green_gpio, GPIO.OUT)
GPIO.setup(blue_gpio,  GPIO.OUT)

04.py

## Init the GPIO PWMs
Freq  = 100 #Hz

RED   = GPIO.PWM(red_gpio, Freq)
RED.start(0)

GREEN = GPIO.PWM(green_gpio, Freq)
GREEN.start(0)

BLUE  = GPIO.PWM(blue_gpio, Freq)
BLUE.start(0)

05.py

# Update the hue with R G B values
def updateHue(R, G, B):
	rVal = 100 - (R/255.0)*100	# Will have to change these values depending on
	gVal = 100 - (G/255.0)*100	#  whether your LED has a common cathode or common
	bVal = 100 - (B/255.0)*100	#  anode. This code is for common anode.
	print "rgb(%.2f, %.2f, %.2f)" % (rVal, gVal, bVal)
	RED.ChangeDutyCycle(rVal)
	GREEN.ChangeDutyCycle(gVal)
	BLUE.ChangeDutyCycle(bVal)

06.py

rVal = (R/255.0)*100			# Common Cathode (Ground)
rVal = 100 - (R/255.0)*100		# Common Anode (5V)

07.py

def rgb():
	updateHue(255,0,0); time.sleep(2)
	updateHue(0,255,0); time.sleep(2)
	updateHue(0,0,255); time.sleep(2)

08.py

def main():
	rgb()
	updateHue(0,0,0); # Light off
	
main()

09.py

def main():
	...
	# Instantiate Pubnub
	pubnub = Pubnub(publish_key = 'your-pub-key',
					subscribe_key = 'your-sub-key')

	# This is the channel your Pi will be listening on for RGB values
	channel = 'phue' 

	# This callback handles any messages received on subscribed channel
	def _callback(msg, n):
		print(msg)
		updateHue(msg["RED"], msg["GREEN"], msg["BLUE"])

	def _error(m):
		print(m)

	pubnub.subscribe(channels=channel, callback=_callback, error=_error)

10.gradle

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.pubnub:pubnub:3.7.3'
}

10.java

package me.kevingleason.phue;

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.SeekBar;
import android.widget.TextView;
import com.pubnub.api.Callback;
import com.pubnub.api.Pubnub;
import com.pubnub.api.PubnubError;
import org.json.JSONException;
import org.json.JSONObject;


public class MainActivity extends Activity {
    public static final int COLOR_RED   = 0;  // Arbitrary ID's
    public static final int COLOR_BLUE  = 1;  //  that are used
    public static final int COLOR_GREEN = 2;  //  later in the code

    SeekBar mRedSeek, mGreenSeek, mBlueSeek;  // All our layout pieces
    LinearLayout mRGBValueHolder;  		      //  that we will be editing

	// Pubnub instance and all the keys you will need to stream data 
    private Pubnub mPubNub;
    public static final String PUBLISH_KEY = "your-pub-key";
    public static final String SUBSCRIBE_KEY = "your-sub-key";
    public static final String CHANNEL = "phue";

    private long lastUpdate = System.currentTimeMillis();  // Used to thereshold
	...
}

11.java

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Instantiate PubNub. We will cover this shortly.
    initPubNub();

    // Get Seek Bars. They will be at R.id.<your-seekbar-id>
    mRedSeek   = (SeekBar) findViewById(R.id.red_seek);
    mGreenSeek = (SeekBar) findViewById(R.id.green_seek);
    mBlueSeek  = (SeekBar) findViewById(R.id.blue_seek);
    mRGBValueHolder = (LinearLayout) findViewById(R.id.rgb_value_holder);

    // Setup Seek Bars. We will cover this function shortly.
    setupSeekBar(mRedSeek,   COLOR_RED);
    setupSeekBar(mGreenSeek, COLOR_GREEN);
    setupSeekBar(mBlueSeek,  COLOR_BLUE);
}

12.java

public void initPubNub(){
    this.mPubNub = new Pubnub(
            PUBLISH_KEY,
            SUBSCRIBE_KEY
    );
    this.mPubNub.setUUID("AndroidPHue");
    subscribe();
}

13.java

public void subscribe(){
    try {
        this.mPubNub.subscribe(CHANNEL, new Callback() {
            @Override
            public void successCallback(String channel, Object message) {
                Log.d("PUBNUB","SUBSCRIBE : " + channel + " : "
                        + message.getClass() + " : " + message.toString());
            }
        });

    } catch (Exception e) {
        e.printStackTrace();
    }
}

14.java

public void setupSeekBar(SeekBar seekBar, final int colorID){
    seekBar.setMax(255);        // Seek bar values goes 0-255
    seekBar.setProgress(255);   // Set the knob to 255 to start
    seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

        @Override
        public void onStopTrackingTouch(SeekBar seekBar) {
            publish(mRedSeek.getProgress(), mGreenSeek.getProgress(), mBlueSeek.getProgress());
        }

        @Override
        public void onStartTrackingTouch(SeekBar seekBar) {
            publish(mRedSeek.getProgress(), mGreenSeek.getProgress(), mBlueSeek.getProgress());
        }

        @Override
        public void onProgressChanged(SeekBar seekBar, int progress,
                                      boolean fromUser) {
            TextView colorValueText;
            switch (colorID){  // Get the TextView identified by the colorID
                case COLOR_RED:
                    colorValueText = (TextView)findViewById(R.id.red_value);
                    break;
                case COLOR_GREEN:
                    colorValueText = (TextView) findViewById(R.id.green_value);
                    break;
                case COLOR_BLUE:
                    colorValueText = (TextView)findViewById(R.id.blue_value);
                    break;
                default:
                    Log.e("SetupSeek","Invalid color.");
                    return;
            }
            colorValueText.setText(String.valueOf(progress));  // Update the 0-255 text
            int red   = mRedSeek.getProgress();     // Get Red value 0-255
            int green = mGreenSeek.getProgress();   // Get Grn value 0-255
            int blue  = mBlueSeek.getProgress();    // Get Blu value 0-255
            updateRGBViewHolderColor(red, green, blue); // Change the background of the viewholder

            long now = System.currentTimeMillis();    // Only allow 1 pub every 100 milliseconds
            if (now - lastUpdate > 100 && fromUser) { // Threshold and only send when user sliding
                lastUpdate = now;
                publish(red, green, blue);            // Stream RGB values to the Pi
            }
        }
    });
}

15.java

private void updateRGBViewHolderColor(int red, int green, int blue){
    int alpha = 255; // No opacity
    int color = (alpha << 24) | (red << 16) | (green << 8) | blue;
    mRGBValueHolder.setBackgroundColor(color);
}

16.java

public void publish(int red, int green, int blue){
    JSONObject js = new JSONObject();
    try {
        js.put("RED",   red);
        js.put("GREEN", green);
        js.put("BLUE",  blue);
    } catch (JSONException e) { e.printStackTrace(); }

    Callback callback = new Callback() {
        public void successCallback(String channel, Object response) {
            Log.d("PUBNUB",response.toString());
        }
    };
    this.mPubNub.publish(CHANNEL, js, callback);
}

17.java

public void setRGBSeeks(int red, int green, int blue){
    mRedSeek.setProgress(red);
    mGreenSeek.setProgress(green);
    mBlueSeek.setProgress(blue);
}

18.java

public void lightOff(View view){
    publish(0, 0, 0);     // 0,0,0 is black or OFF
    setRGBSeeks(0, 0, 0);
}

public void lightOn(View view){
    publish(255, 255, 255); // 255,255,255 is White or ON
    setRGBSeeks(255, 255, 255);
}

19.java

public void initPubNub(){
    this.mPubNub = new Pubnub(
            PUBLISH_KEY,
            SUBSCRIBE_KEY
    );
    this.mPubNub.setUUID("AndroidPHue");
    hereNow();	 // Check if any light is on the channel before you join
    subscribe();
}

20.java

public void hereNow(){
    this.mPubNub.hereNow(CHANNEL, new Callback() {
        @Override
        public void successCallback(String channel, Object response) {
            Log.d("PUBNUB", response.toString());
            try {
                JSONObject json = (JSONObject) response;
                if (json.getInt("occupancy") == 0){
                    setRGBSeeks(0,0,0);
                    MainActivity.this.runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            Toast.makeText(MainActivity.this,"No Light Detected.", Toast.LENGTH_LONG).show();
			    // Do something to views...
                        }
                    });
                }
            } catch (JSONException e){ e.printStackTrace(); }
        }

        @Override
        public void errorCallback(String channel, PubnubError error) {
            Log.d("PUBNUB", error.toString());
        }
    });
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="me.kevingleason.phue" >

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
   
   ...
</manifest>

colors.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- colors.xml -->
<resources>
    <color name="red">#FFFF0000</color>
    <color name="green">#00FF00</color>
    <color name="blue">#0000FF</color>
</resources>

main_activity.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:orientation="vertical">
    
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="72dp">
        <Button
            android:onClick="lightOn"
            style="@style/AppTheme.Button"
            android:text="@string/on_button"/>
        <ImageButton
            android:src="@drawable/phue"
            android:scaleType="centerCrop"
            style="@style/AppTheme.Button"/>
        <Button
            android:onClick="lightOff"
            style="@style/AppTheme.Button"
            android:text="@string/off_button"/>
    </LinearLayout>

    <SeekBar
        android:id="@+id/red_seek"
        style="@style/AppTheme.SeekBar"
        android:background="@color/red" />

    <SeekBar
        android:id="@+id/green_seek"
        style="@style/AppTheme.SeekBar"
        android:background="@color/green" />

    <SeekBar
        android:id="@+id/blue_seek"
        style="@style/AppTheme.SeekBar"
        android:background="@color/blue" />

    <LinearLayout
        android:id="@+id/rgb_value_holder"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <TextView
            android:id="@+id/red_value"
            android:textColor="@color/red"
            android:text="255"
            style="@style/AppTheme.RGB"/>
        <TextView
            android:id="@+id/green_value"
            android:textColor="@color/green"
            android:text="255"
            style="@style/AppTheme.RGB"/>
        <TextView
            android:id="@+id/blue_value"
            android:textColor="@color/blue"
            android:text="255"
            style="@style/AppTheme.RGB"/>

    </LinearLayout>
</LinearLayout>

strings.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- main/res/values/strings.xml -->
<resources>
    <string name="app_name">PHue</string>
    <string name="hello_world">Hello world!</string>
    <string name="action_settings">Settings</string>
    <string name="on_button">ON</string>
    <string name="off_button">OFF</string>
</resources>

styles.xml

<resources>
	<!-- main/res/values/styles.xml -->
    <!-- Base application theme. -->
    <style name="AppTheme" parent="android:Theme.Holo.Light.DarkActionBar">
        <!-- Customize your theme here. -->
    </style>

	<!-- This is the container or RGB values -->
    <style name="AppTheme.RGB">
        <item name="android:layout_width">0dp</item>
        <item name="android:layout_height">match_parent</item>
        <item name="android:layout_weight">1</item>
        <item name="android:gravity">center</item>
        <item name="android:textSize">40sp</item>
        <item name="android:textStyle">bold</item>
    </style>

	<!-- The seek bar slider styles -->
    <style name="AppTheme.SeekBar">
        <item name="android:layout_width">match_parent</item>
        <item name="android:layout_height">wrap_content</item>
        <item name="android:padding">25dp</item>
    </style>

	<!-- The on and off button styles -->
    <style name="AppTheme.Button">
        <item name="android:layout_width">0dp</item>
        <item name="android:layout_height">match_parent</item>
        <item name="android:layout_weight">1</item>
        <item name="android:background">#000</item>
        <item name="android:textSize">20sp</item>
        <item name="android:textColor">#fff</item>
    </style>
</resources>