我正在尝试通过蓝牙发送字符串消息。我正在使用这篇文章中的代码：send message
我想在 OnClick() 上向另一个连接的设备发送消息。目前我可以显示配对的设备，我可以与它们连接。
P.S 我正在尝试在 write() 函数中发送消息。当我尝试调试代码时，我发现调试器不会在 MESSAGE WRITE 语句上输入 MESSAGE READ。感谢您的帮助。
public class BluetoothActivity extends AppCompatActivity {
public static final int REQUEST_ENABLE_BT=1;
ListView lv_paired_devices;
Button sendMessage;
Set<BluetoothDevice> set_pairedDevices;
ArrayAdapter adapter_paired_devices;
BluetoothAdapter bluetoothAdapter;
public static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
public static final int MESSAGE_READ=0;
public static final int MESSAGE_WRITE=1;
public static final int CONNECTING=2;
public static final int CONNECTED=3;
public static final int NO_SOCKET_FOUND=4;
String bluetooth_message="00";
@SuppressLint("HandlerLeak")
Handler mHandler=new Handler()
{
@Override
public void handleMessage(Message msg_type) {
super.handleMessage(msg_type);
switch (msg_type.what){
case MESSAGE_READ:
byte[] readbuf=(byte[])msg_type.obj;
String string_recieved=new String(readbuf);
Log.i("TAGREAD", "Bluetooth not supported");
Toast.makeText(getApplicationContext(),string_recieved,Toast.LENGTH_LONG).show();
//do some task based on recieved string
break;
case MESSAGE_WRITE:
if(msg_type.obj!=null){
ConnectedThread connectedThread=new ConnectedThread((BluetoothSocket)msg_type.obj);
connectedThread.write(bluetooth_message.getBytes());
Log.i("TAGWRITE", "Bluetooth not supported");
}
break;
case CONNECTED:
Toast.makeText(getApplicationContext(),"Connected",Toast.LENGTH_SHORT).show();
break;
case CONNECTING:
Toast.makeText(getApplicationContext(),"Connecting...",Toast.LENGTH_SHORT).show();
break;
case NO_SOCKET_FOUND:
Toast.makeText(getApplicationContext(),"No socket found",Toast.LENGTH_SHORT).show();
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getSupportActionBar().setTitle("Sparowane urządzenia");
bluetoothAdapter=BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter == null) {
Log.i("TAGTAG", "Bluetooth not supported");
// Show proper message here
finish();
}
else{
setContentView(R.layout.activity_bluetooth);
initialize_layout();
initialize_bluetooth();
start_accepting_connection();
initialize_clicks();
}
}
public void start_accepting_connection()
{
//call this on button click as suited by you
AcceptThread acceptThread = new AcceptThread();
acceptThread.start();
Toast.makeText(getApplicationContext(),"accepting",Toast.LENGTH_SHORT).show();
}
public void initialize_clicks()
{
lv_paired_devices.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id)
{
Object[] objects = set_pairedDevices.toArray();
BluetoothDevice device = (BluetoothDevice) objects[position];
ConnectThread connectThread = new ConnectThread(device);
connectThread.start();
Toast.makeText(getApplicationContext(),"device choosen "+device.getName(),Toast.LENGTH_SHORT).show();
}
});
}
public void initialize_layout()
{
lv_paired_devices = (ListView)findViewById(R.id.lv_paired_devices);
adapter_paired_devices = new ArrayAdapter(getApplicationContext(),R.layout.support_simple_spinner_dropdown_item);
lv_paired_devices.setAdapter(adapter_paired_devices);
sendMessage=findViewById(R.id.send_button);
}
public void initialize_bluetooth()
{
bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (bluetoothAdapter == null) {
// Device doesn't support Bluetooth
Toast.makeText(getApplicationContext(),"Your Device doesn't support bluetooth. you can play as Single player",Toast.LENGTH_SHORT).show();
finish();
}
//Add these permisions before
// <uses-permission android:name="android.permission.BLUETOOTH" />
// <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
// <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
// <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
if (!bluetoothAdapter.isEnabled()) {
Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
}
else {
set_pairedDevices = bluetoothAdapter.getBondedDevices();
if (set_pairedDevices.size() > 0) {
for (BluetoothDevice device : set_pairedDevices) {
String deviceName = device.getName();
String deviceHardwareAddress = device.getAddress(); // MAC address
adapter_paired_devices.add(device.getName() + "\n" + device.getAddress());
}
}
}
}
public class AcceptThread extends Thread
{
private final BluetoothServerSocket serverSocket;
public AcceptThread() {
BluetoothServerSocket tmp = null;
try {
// MY_UUID is the app's UUID string, also used by the client code
tmp = bluetoothAdapter.listenUsingRfcommWithServiceRecord("NAME",MY_UUID);
} catch (IOException e) { }
serverSocket = tmp;
}
public void run() {
BluetoothSocket socket = null;
// Keep listening until exception occurs or a socket is returned
while (true) {
try {
socket = serverSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null)
{
// Do work to manage the connection (in a separate thread)
mHandler.obtainMessage(CONNECTED).sendToTarget();
}
}
}
}
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
// Use a temporary object that is later assigned to mmSocket,
// because mmSocket is final
BluetoothSocket tmp = null;
mmDevice = device;
// Get a BluetoothSocket to connect with the given BluetoothDevice
try {
// MY_UUID is the app's UUID string, also used by the server code
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) { }
mmSocket = tmp;
}
public void run() {
// Cancel discovery because it will slow down the connection
bluetoothAdapter.cancelDiscovery();
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mHandler.obtainMessage(CONNECTING).sendToTarget();
mmSocket.connect();
} catch (IOException connectException) {
// Unable to connect; close the socket and get out
try {
mmSocket.close();
} catch (IOException closeException) { }
return;
}
// Do work to manage the connection (in a separate thread)
// bluetooth_message = "Initial message"
// mHandler.obtainMessage(MESSAGE_WRITE,mmSocket).sendToTarget();
}
/** Will cancel an in-progress connection, and close the socket */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the input and output streams, using temp objects because
// member streams are final
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[2]; // buffer store for the stream
int bytes; // bytes returned from read()
// Keep listening to the InputStream until an exception occurs
while (true) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer).sendToTarget();
Toast.makeText(BluetoothActivity.this,bytes,Toast.LENGTH_LONG).show();
} catch (IOException e) {
break;
}
}
}
/* Call this from the main activity to send data to the remote device */
public void write(byte[] bytes) {
sendMessage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
try {
mmOutStream.write(bytes);
} catch (IOException e) { }
}
});
}
/* Call this from the main activity to shutdown the connection */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}