Android bluetooth communication (listView.setOnItemClickListener)

Question

У меня возникают проблемы с реализацией вызова сервера классов и клиента для установления связи между Bluetooth. Мне нужна помощь, я новичок в программировании на Android. Я вставлю свой код. Я USand, и этот метод для тестирования по основной идее будет состоять в использовании классов.

ListaBluetooth.java 

53 mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); 
54 
55 Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices(); 
56 // If there are paired devices 
57 if (pairedDevices.size() > 0) { 
58 // Loop through paired devices 
59 for (BluetoothDevice device:pairedDevices) { 
60 // Add the name and address to an array adapter to show in a 
ListView 
61 mArrayAdapter.add(device.getName() + "\n" + device.getAddress()); 
62 
63 } 
64 } 
65 
66 
67 listView.setOnItemClickListener(new OnItemClickListener() { 
68 
69 @Override 
70 public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, 
71 long arg3) { 
72 // TODO Auto-generated method stub 
73 Conecta(); 
74 } 
75 }); 
76 
77 
78 } 
79 
80 
81 public void Conecta(){ 
82 try { 
83 // Standard SerialPortService ID 
84 UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb"); 
85 mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid); 
86 mmSocket.connect(); 
87 mmOutputStream = mmSocket.getOutputStream(); 
88 mmInputStream = mmSocket.getInputStream(); 
89 
90 //beginListenForData(); 
91 
92 myLabel.setText("Bluetooth Opened"); 
93 } catch (NullPointerException e) { 
94 e.printStackTrace(); 
95 } catch (Exception e) { 
96 e.printStackTrace(); 
97 } 
98 
99 } 

Erros

11-26 00:21:03.582: W/System.err(20027): java.lang.NullPointerException 
11-26 00:21:03.592: W/System.err(20027): at com.example.smarthome.ListaBluetooth.Conecta(ListaBluetooth.java:85) 
11-26 00:21:03.592: W/System.err(20027): at com.example.smarthome.ListaBluetooth$1.onItemClick(ListaBluetooth.java:73) 
11-26 00:21:03.592: W/System.err(20027): at android.widget.AdapterView.performItemClick(AdapterView.java:301) 
11-26 00:21:03.592: W/System.err(20027): at android.widget.AbsListView.performItemClick(AbsListView.java:1280) 
11-26 00:21:03.592: W/System.err(20027): at android.widget.AbsListView$PerformClick.run(AbsListView.java:3071) 
11-26 00:21:03.592: W/System.err(20027): at android.widget.AbsListView$1.run(AbsListView.java:3973) 
11-26 00:21:03.592: W/System.err(20027): at android.os.Handler.handleCallback(Handler.java:615) 
11-26 00:21:03.592: W/System.err(20027): at android.os.Handler.dispatchMessage(Handler.java:92) 
11-26 00:21:03.592: W/System.err(20027): at android.os.Looper.loop(Looper.java:137) 
11-26 00:21:03.592: W/System.err(20027): at android.app.ActivityThread.main(ActivityThread.java:4867) 
11-26 00:21:03.602: W/System.err(20027): at java.lang.reflect.Method.invokeNative(Native Method) 
11-26 00:21:03.602: W/System.err(20027): at java.lang.reflect.Method.invoke(Method.java:511) 
11-26 00:21:03.602: W/System.err(20027): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1007) 
11-26 00:21:03.602: W/System.err(20027): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:774) 
11-26 00:21:03.602: W/System.err(20027): at dalvik.system.NativeStart.main(Native Method) 
11-26 00:22:03.642: W/IInputConnectionWrapper(20027): getSelectedText on inactive InputConnection 
11-26 00:22:03.642: W/IInputConnectionWrapper(20027): setComposingText on inactive InputConnection 
11-26 00:22:03.642: W/IInputConnectionWrapper(20027): getExtractedText on inactive InputConnection 





Main 
18 public class MainActivity extends Activity { 
19 
20 
21 @Override 
22 protected void onCreate(Bundle savedInstanceState) { 
23 super.onCreate(savedInstanceState); 
24 setContentView(R.layout.activity_main); 
25 
26 
27 } 
28 
29 @Override 
30 public boolean onCreateOptionsMenu(Menu menu) { 
31 // Inflate the menu; this adds items to the action bar if it is present. 
32 getMenuInflater().inflate(R.menu.main, menu); 
33 return true; 
34 } 
35 
36 public void ChamaContador(View v) 
37 { 
38 setContentView(R.layout.contador_main); 
39 } 
40 public void ChamaMain(View v) 
41 { 
42 setContentView(R.layout.activity_main); 
43 } 
44 
45 public void ChamaMenuPrincipal(View v){ 
46 setContentView(R.layout.acionar_main); 
47 } 
48 
49 public void ChamaAtivarBluetooth(View v){ 
50 Intent myIntent = new Intent(MainActivity.this, AtivaBluetooth.class); 
51 startActivity(myIntent); 
52 } 
53 public void ChamaLista(View v){ 
54 setContentView(R.layout.lista_main); 
55 } 
56 public void ChamaConexao(View v){ 
57 Intent myIntent = new Intent(MainActivity.this, ListaBluetooth.class); 
58 startActivity(myIntent); 
59 } 
60 } 








10 public class ServidorBluetooth { 
11 UUID MEU_UUID = null; 
12 BluetoothAdapter mbtadapter = null; 
13 BluetoothServerSocket mmServerSocket = null; 
14 
15 public ServidorBluetooth(BluetoothAdapter adapter, String uuid) { 
16 // Use a temporary object that is later assigned to mmServerSocket, 
17 // because mmServerSocket is final 
18 BluetoothServerSocket tmp = null; 
19 MEU_UUID = UUID.fromString(uuid); 
20 mbtadapter = adapter; 
21 
22 
23 try { 
24 // MY_UUID is the app's UUID string, also used by the client code 
25 tmp = mbtadapter.listenUsingRfcommWithServiceRecord("Home Server", 
MEU_UUID); 
26 } catch (IOException e) { } 
27 mmServerSocket = tmp; 
28 } 
29 
30 public void run() throws IOException { 
31 BluetoothSocket socket = null; 
32 // Keep listening until exception occurs or a socket is returned 
33 while (true) { 
34 try { 
35 socket = mmServerSocket.accept(); 
36 } catch (IOException e) { 
37 break; 
38 } 
39 // If a connection was accepted 
40 if (socket != null) { 
41 // Do work to manage the connection (in a separate thread) 
42 manageConnectedSocket(socket); 
43 mmServerSocket.close(); 
44 break; 
45 } 
46 } 
47 } 
48 
49 private void manageConnectedSocket(BluetoothSocket socket) { 
50 // TODO Auto-generated method stub 
51 
52 } 
53 
54 /** Will cancel the listening socket, and cause the thread to finish */ 
55 public void cancel() { 
56 try { 
57 mmServerSocket.close(); 
58 } catch (IOException e) { } 
59 } 
60 } 

Answer 1

Из журналов ошибок, кажется, как ваша переменная mmDevice является null. Где вы объявляете и инициализируете или назначаете эту переменную?

Answer 2

в ListaBluetooth.java,

mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); // This is your bluetooth adapter. 
//... 
public void Conecta(){ 
    try { 
     // Standard SerialPortService ID 
     UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb"); 
     // mmSocket = mmDevice.createRfcommSocketToServiceRecord(uuid); // This line is wrong. Should change like next line. 
     mmSocket = mBluetoothAdapter.createRfcommSocketToServiceRecord(uuid); 
     // ... 
    } 
}