前提

１．AndroidのServiceでBluetooth端末の検出を行い、
２．検出したデバイスのリストをAndroidで動作するUnity上のUIに投げ、
３．Unity上で選択したデバイスにAndroidのServiceで接続
という流れを実装中です。

環境

Android: 4.2.2

問題・質問

Service内で定義したBluetooth端末検出・接続用のクラス（BTManager）において、BluetoothAdapter#startDiscovery（端末の検索）のアクションを受け取るレシーバーが動作しません。
アクションの受け取りは、IntentFilterとBroadcastReceiverを用いて下記ソース（関数StartConnect内）のように実装しています。
どこに誤りがあるのか、ご教授いただけると幸いです。

ソース（BTManager）

Java
1import android.bluetooth.BluetoothAdapter;
2import android.bluetooth.BluetoothDevice;
3import android.content.BroadcastReceiver;
4import android.content.Context;
5import android.content.Intent;
6import android.content.IntentFilter;
7
8import java.util.ArrayList;
9import java.util.List;
10import java.util.Set;
11
12/**
13 * Created by inca on 16/10/04.
14 */
15public class BTManager {
16    private BluetoothAdapter ba;
17
18    private String device_name;
19
20    private BluetoothClientThread bct;
21    private BluetoothServerThread bst;
22
23    private Context service_context;
24    private List<BluetoothDevice> mDeviceList;
25
26    public BTManager(Context service_context){
27        this.service_context = service_context;
28        mDeviceList = new ArrayList<BluetoothDevice>();
29    }
30
31    public void SendNode(int index, String name, String addr) {}
32
33    public void SendConnectionResult(boolean is_connect, String msg){}
34
35    public void StartConnect() {
36        System.out.println("in BTManager start_connect");
37
38        ba = BluetoothAdapter.getDefaultAdapter();
39
40        Set<BluetoothDevice> pairedDevices = ba.getBondedDevices();
41
42        if (pairedDevices.size() > 0) {
43            //接続履歴のあるデバイスが存在する
44            System.out.println("with pairred devices");
45            int index = 0;
46            for (BluetoothDevice device : pairedDevices) {
47                System.out.println("detect device");
48                mDeviceList.add(device);
49                SendNode(index, device.getName(), device.getAddress());
50                System.out.println("send to unity: " + index);
51                index += 1;
52            }
53        }else{
54            //接続履歴のあるデバイスが存在しない
55            System.out.println("without pairred devices");
56            IntentFilter filter = new IntentFilter();
57            filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
58            filter.addAction(BluetoothDevice.ACTION_FOUND);
59            filter.addAction(BluetoothDevice.ACTION_NAME_CHANGED);
60            filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
61
62            service_context.registerReceiver(DeviceFoundReceiver, filter);
63
64            if(ba.isDiscovering()){
65                ba.cancelDiscovery();
66            }
67
68            ba.startDiscovery();
69        }
70    }
71
72    private final BroadcastReceiver DeviceFoundReceiver = new BroadcastReceiver(){
73        private int index = 0;
74
75        //検出されたデバイスからのブロードキャストを受ける
76        @Override
77        public void onReceive(Context context, Intent intent){
78            String action = intent.getAction();
79            String dName = null;
80            BluetoothDevice foundDevice;
81
82            if(BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)){
83                System.out.println("device discover start");
84            }
85            if(BluetoothDevice.ACTION_FOUND.equals(action)){
86                System.out.println("device found");
87                foundDevice = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
88                if((dName = foundDevice.getName()) != null){
89                    SendNode(index, dName, foundDevice.getAddress());
90                    mDeviceList.add(foundDevice);
91                }
92            }
93            if(BluetoothDevice.ACTION_NAME_CHANGED.equals(action)){
94                System.out.println("device found with name change");
95                foundDevice = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
96                if(foundDevice.getBondState() != BluetoothDevice.BOND_BONDED){
97                    SendNode(index, dName, foundDevice.getAddress());
98                    mDeviceList.add(foundDevice);
99                }
100            }
101
102            if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){
103                System.out.println("device discover end");
104            }
105        }
106    };
107
108    public void Connecting(int index){
109        System.out.println("index : " + index);
110        System.out.println("mDeviceList.size : " + mDeviceList.size());
111        BluetoothDevice device = mDeviceList.get(index);
112        bct = new BluetoothClientThread(device, ba){
113            @Override
114            public void CallbackConnectionResult(boolean is_connect, String msg){
115                SendConnectionResult(is_connect, msg);
116            }
117        };
118
119        bct.start();
120    }
121
122}
123

ソース（Serviceクラス該当部分）

Java
1public class ConnectionService extends Service {
2
3    static final String TAG="LocalService";
4
5    private final BTManager mBTManager = new BTManager(this){
6        @Override
7        public void SendNode(int index, String name, String addr) {
8            MessageToUnity mtu = new MessageToUnity("node", index, name, addr, false);
9            try {
10                String mtu_json = LoganSquare.serialize(mtu);
11                mTCPClientForUnity.SendToUnity(mtu_json);
12            }catch (IOException e){
13                e.getStackTrace();
14            }
15        }
16
17        @Override
18        public void SendConnectionResult(boolean is_connect, String msg){
19            MessageToUnity mtu = new MessageToUnity("connection", 0, "", "", is_connect);
20            try {
21                String mtu_json = LoganSquare.serialize(mtu);
22                mTCPClientForUnity.SendToUnity(mtu_json);
23            }catch (IOException e){
24                e.getStackTrace();
25            }
26        }
27    };