Harman Kardon Android SDK Tutorial

About this tutorial

This project is built for Android 4.0 minimum Prequisites are Android Studio 0.8.6

This tutorial leads you through the creation of a simple app that uses the Harman Kardon Android SDK to play an audio track on your speaker. We show you how to:

This is an image of the file that we are creating

Creating a Project

Open Android Studio and create a New Project.

Set the Minimum SDK version to "API level 14: Android 4.0 (Ice Cream Sandwich)".

When you are asked to "Add an activity to Mobile", select Blank Activity.

Give the activity the name Device_List, the layout the name device_list, and the title Device List.

Updating the Library

In a file explorer (not Android Studio), drag the HKWirelessHD.jar files into the /app/libs directory in your project's root directory.

Adding to the Gradle

In Android studio right click on the app pane on the left hand side. Go to Folder> JNI folder. Name the folder jniLibs click Finish and a new folder will be created. Copy the libHKWirelessHD.SO files into this folder

Go to the build.gradle for the Module app then add following line to the dependencies compile files('libs/HKWirelessHD.jar')

Your dependencies should look like this

dependencies {                                     
    compile 'com.android.support:support-v4:19.1.0'
    compile files('libs/HKWirelessHD.jar')         
}

Creating the Layouts

There are 2 layouts that we need for this project. The first contains a ListView for the devices, and buttons to control the playback of the device. The second is the item layout for the ListView.

First create an Acitivity called Device_List and add the following items to the XML

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <ListView
        android:id="@+id/device_list"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="50dp" >
    </ListView>
    <Button
        android:id="@+id/refresh_btn"
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:layout_alignParentBottom="true"
        android:text="Refresh"  />
    <Button
        android:id="@+id/play_btn"
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:layout_toRightOf="@id/refresh_btn"
        android:layout_alignParentBottom="true"
        android:text="Play"  />
    <Button
        android:id="@+id/pause_btn"
        android:layout_width="100dp"
        android:layout_height="50dp"
        android:layout_toRightOf="@id/play_btn"
        android:layout_alignParentBottom="true"
        android:text="Pause"  />
</RelativeLayout>

Then, create a file device_list_item.xml. This has a TextView and a checkbox to change whether we are playing to that device or not

<?xml version="1.0" encoding="utf-8"?>    
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:orientation="horizontal" 
    android:layout_width="fill_parent"        
    android:layout_height="50dp"
    android:id="@+id/device_list_item"> 


    <TextView android:id="@+id/device_name" 
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content"
        android:layout_marginLeft="5dp"
        android:layout_marginTop="10dp" 
        android:textSize="35px" />

    <CheckBox
        android:id="@+id/select"
        android:layout_alignParentRight="true"
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:focusable="false"
        android:clickable="false"
        android:focusableInTouchMode="false"
        android:checked="false" />

</RelwativeLayout>

Creating a Utilities Class

Before we make the activity, we make a Utility class. This Utilities class will use the HKWirelessHandler class from the Library we import at the beginning. Create a class called Util

First we will create some signaling integers for sharing information between the Activity and the Service

public static final int MSG_PCM_PLAY = 2;
public static final int MSG_PCM_PAUSE = 3;

public static final String MSG_TYPE_MUSIC = "msg";
public static final String MSG_URL_MUSIC = "url";

We then create an inner class called DeviceData, which will store a list of devices connected to your WiFi

public class DeviceData {
    public DeviceObj deviceObj;
    public Boolean status;
}

private List<DeviceData> devices = new ArrayList<DeviceData>();

Now, lets create an instance of HKWirelessHandler and an Instance using the singleton pattern

public  HKWirelessHandler hkwireless = new HKWirelessHandler();
private static Util instance = new Util();


public static Util getInstance() {
    return instance;
}

Now, create 4 functions for initializing the speaker and getting information about the current devices

public void initDeviceInfor() {
    synchronized (this) {
        devices.clear();
        if (!hkwireless.isInitialized())return;

        for (int i=0; i<hkwireless.getDeviceCount(); i++) {
            DeviceData device = new DeviceData();
            device.deviceObj = hkwireless.getDeviceInfoByIndex(i);
            device.status = hkwireless.isDeviceActive(device.deviceObj.deviceId);
            devices.add(device);
        }
    }
}

public void refreshDeviceInfoOnce(){
    hkwireless.refreshDeviceInfoOnce();
}

public List<DeviceData> getDevices() {
    return devices;
}

public boolean getDeviceStatus(int position) {
    return devices.get(position).status;
}

Now, we need to add methods update the device status and add or remove devices

public void updateDeviceStatus(long deviceid){
    for (int i=0; i<devices.size(); i++) {
        DeviceData device = devices.get(i);
        if (device.deviceObj.deviceId == deviceid) {
            device.deviceObj = hkwireless.findDeviceFromList(deviceid);
            if (device.deviceObj == null) {
                devices.remove(i);
            } else {
                device.status = hkwireless.isDeviceActive(device.deviceObj.deviceId);
                devices.set(i, device);
            }
            break;
        }
    }
}

public boolean removeDeviceFromSession(long deviceid){
    boolean ret = hkwireless.removeDeviceFromSession(deviceid);
    if (ret) {
        updateDeviceStatus(deviceid);
    }
    return ret;
}

public boolean addDeviceToSession(long deviceid){
    boolean ret = hkwireless.addDeviceToSession(deviceid);
    if (ret) {
        updateDeviceStatus(deviceid);
    }
    return ret;
}

Create The Activity

Now we add to the activity which connects the Utilities class to the front end. Go to Device_List.java which was created earlier.

First we need some constants. One a URL for the song we are going to play, the second which is the Key to Activate the Key and a copy of the Utilities class

String url="/storage/emulated/0/Music/Bowling for Soup/1985.mp3";

private static final String KEY = "2FA8-2FD6-C27D-47E8-A256-D011-3751-2BD6";

private Util util= Util.getInstance();

Now, we setup an inner class for an Adapter. This will allow us to create the custom ListView we need.

class DeviceAdapter extends BaseAdapter {
    private LayoutInflater mInflater;

    public DeviceAdapter(Context context){
        this.mInflater=LayoutInflater.from(context);
    }

    public int getCount() {
        return util.getDevices().size();
    }

    public Object getItem(int position) {
        return util.getDevices().get(position);
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(final int position, View convertView, ViewGroup parent) {
        convertView = mInflater.inflate(R.layout.device_list_item, null);
        final TextView textView = (TextView)convertView.findViewById(R.id.device_name);
        final CheckBox checkbox = (CheckBox)convertView.findViewById(R.id.select);


        textView.setText(util.getDevices().get(position).deviceObj.deviceName);
        if (util.getDeviceStatus(position)) {
            checkbox.setChecked(true);
        } else {
            checkbox.setChecked(false);
        }

        convertView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View arg0) {
                if (util.getDeviceStatus(position)) {
                    util.removeDeviceFromSession(util.getDevices().get(position).deviceObj.deviceId);
                    checkbox.setChecked(false);
                } else {
                    util.addDeviceToSession(util.getDevices().get(position).deviceObj.deviceId);
                    checkbox.setChecked(true);
                }
            }
        });
        return convertView;
    }
}

Next we override the onCreate, we initialize the HK Wireless and then overriding the onClick for the buttons we created earlier

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.devicelist);

    /**Registering overriding methods for the Wireless Controller**/
     * Over here you can override the methods to let your app react to
     * events tht happen on the speaker
     **/
    util.hkwireless.registerHKWirelessControllerListener(new HKWirelessListener() {

        @Override
        public void onPlayEnded() {}

        @Override
        public void onPlaybackStateChanged(int arg0) {}

        @Override
        public void onPlaybackTimeChanged(int arg0) {}

        @Override
        public void onVolumeLevelChanged(long deviceId, int deviceVolume,int avgVolume) {}

        @Override
        public void onDeviceStateUpdated(long deviceId, int reason) {}

        @Override
        public void onErrorOccurred(int errorCode, String errorMsg) {
            Toast.makeText(MainActivity.this, errorMsg, Toast.LENGTH_LONG).show();
        }
    });

    /**Initializing the HK Controller **/
    if (!util.hkwireless.isInitialized()) {
        util.hkwireless.initializeHKWirelessController(KEY);
        if (util.hkwireless.isInitialized()) {
            Toast.makeText(this, "Wireless controller init success", Toast.LENGTH_LONG).show();
        } else {
            Toast.makeText(this, "Wireless controller init fail", Toast.LENGTH_LONG).show();
        }
    }
    /**This call will add the speakers connected to your WiFi **/
    util.initDeviceInfor();

    /*The listView for the list of devices on display*/
    ListView deviceList = (ListView)(this.findViewById(R.id.device_list));
    /*DeviceAdapter for the ListView of devices*/
    DeviceAdapter adapter = new DeviceAdapter(this);
    deviceList.setAdapter(adapter);

    //On Click for the REFRESH button
    (this.findViewById(R.id.refresh_btn)).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            util.refreshDeviceInfoOnce();
        }
    });

    //On click for the PLAY button
    (this).findViewById(R.id.play_btn).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            playMusic();
        }
    });

    //on click pause button
    (this.findViewById(R.id.pause_btn)).setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            pauseMusic();
        }
    });

}

Now, we have to write the methods for playing and pausing music which we mentioned in the onCreate

private void pauseMusic(){
    //start the service to run the Audio Codec
    //we add a message to pause the song
    Intent intent = new Intent();
    intent.putExtra(Util.MSG_URL_MUSIC, url);
    intent.putExtra(Util.MSG_TYPE_MUSIC, Util.MSG_PCM_PAUSE);
    intent.setPackage(MainActivity.this.getPackageName());
    MainActivity.this.startService(intent);
}

private void playMusic() {
    if (util.getDevices().size() == 0) {
        Toast.makeText(this, "No device connected", Toast.LENGTH_LONG).show();
        return;
    }
    List<Util.DeviceData> devices = util.getDevices();
    if (devices.size() <= 0){
        Toast.makeText(this, "No device in use", Toast.LENGTH_LONG).show();
        return;
    }

    for (int i=0; i<devices.size(); i++) {
        if (!util.getDeviceStatus(i)) {
            Toast.makeText(this, "No device in use", Toast.LENGTH_LONG).show();
            return;
        }
    }
    //start the service to run the Audio Codec
    //we add a message to play so that can play the song
    Intent intent = new Intent();
    intent.putExtra(Util.MSG_URL_MUSIC, url);
    intent.putExtra(Util.MSG_TYPE_MUSIC, Util.MSG_PCM_PLAY);
    intent.setPackage(this.getPackageName());
    this.startService(intent);
}

Creating the Service

This is the last part of the Program. We create a Service that starts up. We have already attempted to start the service in the pauseMusic() and playMusic() methods. The service is as follows

private AudioCodecHandler pcmCodec = new AudioCodecHandler();

@Override
public IBinder onBind(Intent arg0) {
    return null;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {

    if (intent != null) {
        int cmd = intent.getIntExtra(Util.MSG_TYPE_MUSIC, 0);
        if (cmd == Util.MSG_PCM_PLAY) {
            final String url = intent.getStringExtra(Util.MSG_URL_MUSIC);
            String songName =  url.substring(url.lastIndexOf("/"));
            pcmCodec.playCAFFromCertainTime(url, songName, 0);
        } else if (cmd == Util.MSG_PCM_PAUSE) {
            pcmCodec.stop();
        }
    }
    return super.onStartCommand(intent, flags, startId);
}

Changing the Manifest

The manifest settings are the last bit of the program that's left. Add these permissions after the activity tag on the Manifest

<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE" />

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"/>
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE"/>
<uses-permission android:name="android.permission.WRITE_SETTINGS"/>

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

Also, we can add the activity to the srvice

<service
    android:name="com.harman.wirelessomni.MusicPlayerService">
    <intent-filter>
        <action android:name="com.harman.wirelessomni.MainActivity" />
    </intent-filter>
</service>

Get the Code

31 Aug 2015