我为我们的项目编写了一个应用程序。
我写过在youtube上观看教程。
通过蓝牙进行通信。
设备已配对并与设备连接，设备会将成功连接字符串发送回终端。
但是我发送的数据没有被设备接收。（有一个用于显示接收数据的Toast消息）。
请澄清，这是我的代码
public class MainActivity extends Activity implements OnItemClickListener {
protected static final int SUCCESS_CONNECT = 0;
protected static final int MESSAGE_READ = 1;
ArrayAdapter<String> listAdapter;
ListView listView;
BluetoothAdapter btAdapter;
Set<BluetoothDevice> devicesArray;
ArrayList<String> pairedDevices;
IntentFilter filter;
BroadcastReceiver receiver;
String tag = "debugging";
ArrayList<BluetoothDevice> devices;
public static UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
Handler mHandler = new Handler(){
public void handleMessage(android.os.Message msg) {
switch(msg.what){
case SUCCESS_CONNECT:
ConnectedThread connectedThread = new ConnectedThread((BluetoothSocket)msg.obj);
Toast.makeText(getApplicationContext(), "Successfully Connected", 0).show();
String s = "Successfully Connected";
connectedThread.write(s.getBytes());
break;
case MESSAGE_READ:
byte[] readbuf = (byte[])msg.obj;
String string = new String(readbuf);
Toast.makeText(getApplicationContext(), string, 0).show();
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
init();
if(btAdapter == null){
Toast.makeText(getApplicationContext(), "No Bluetooth Detected", 0).show();
finish();
}
else{
if(!btAdapter.isEnabled()){
turnOnBT();
}
getPairedDevices();
startDiscovery();
}
}
private void startDiscovery() {
// TODO Auto-generated method stub
btAdapter.cancelDiscovery();
btAdapter.startDiscovery();
}
private void turnOnBT() {
// TODO Auto-generated method stub
Intent intent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(intent, 1);
}
private void getPairedDevices() {
// TODO Auto-generated method stub
devicesArray = btAdapter.getBondedDevices();
if(devicesArray.size()>0){
for(BluetoothDevice device: devicesArray){
pairedDevices.add(device.getName());
}
}
}
//initializes all the variables
private void init() {
// TODO Auto-generated method stub
listView = (ListView)findViewById(R.id.listView);
listView.setOnItemClickListener(this);
listAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,0);
listView.setAdapter(listAdapter);
btAdapter = BluetoothAdapter.getDefaultAdapter();
pairedDevices = new ArrayList<String>();
devices = new ArrayList<BluetoothDevice>();
filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
receiver = new BroadcastReceiver(){
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
// When discovery finds a device
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
// Get the BluetoothDevice object from the Intent
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
devices.add(device);
String s = "";
for(int i = 0 ; i< pairedDevices.size(); i++){
if(device.getName().equals(pairedDevices.get(i))){
s ="(PAIRED)";
break;
}
}
listAdapter.add(device.getName()+" "+s+"\n"+device.getAddress());
}
else if(BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)){
//some code
}
else if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){
//some code
}
else if(BluetoothAdapter.ACTION_STATE_CHANGED.equals(action)){
if(btAdapter.getState() == btAdapter.STATE_OFF){
turnOnBT();
}
}
}
};
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_STARTED);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
registerReceiver(receiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
registerReceiver(receiver, filter);
}
@Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
unregisterReceiver(receiver);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if(resultCode == RESULT_CANCELED){
Toast.makeText(getApplicationContext(), "Bluetooth must be enabled", Toast.LENGTH_SHORT).show();
finish();
}
}
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
//public abstract void onItemClick (AdapterView<?> parent, View view, int position, long id)
// TODO Auto-generated method stub
if(btAdapter.isDiscovering()){
btAdapter.cancelDiscovery();
}
if(listAdapter.getItem(arg2).contains("(PAIRED)")){
//Toast.makeText(getApplicationContext(), "Device is Already Paired", 0).show();
BluetoothDevice selectedDevice = devices.get(arg2);
ConnectThread connect = new ConnectThread(selectedDevice);
connect.start();
Log.i(tag,"in click listener");
}
else{
Toast.makeText(getApplicationContext(), "Device is not Paired", 0).show();
}
}
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
btAdapter.cancelDiscovery();
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
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)
mHandler.obtainMessage(SUCCESS_CONNECT,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; // buffer store for the stream
int bytes; // bytes returned from read()
// Keep listening to the InputStream until an exception occurs
while (true) {
try {
buffer = new byte[1024];
// Read from the InputStream
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer).sendToTarget();
} catch (IOException e) {
break;
}
}
}
/* Call this from the main activity to send data to the remote device */
public void write(byte[] bytes) {
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) { }
}
}
}
答案 0 :(得分：0)
连接蓝牙模块时，从BluetoothDevice对象获取地址。使用以下示例代码连接蓝牙设备。它适合我。
for(BluetoothDevice bt: mBluetoothAdapter.getBondedDevices()) {
if(bt.getName().equalsIgnoreCase(selectedBTDeviceName)) {
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(bt.getAddress());
mBluetoothAdapter.cancelDiscovery();
mBSocket = device.createRfcommSocketToServiceRecord(SPP_UUID);
mBSocket.connect();
return mBSocket;
}
}
您确实使用device.getAddress（）方法创建了BluetoothDevice对象。现在唯一可能出现的问题是你的BroadcastReceiver。
在您从 onCreate（）调用的 init（）方法中，您正在注册 BroadcastReceiver 使用此活动并在 onPause（）中取消注册BroadcastReceiver。
在 onResume（）方法中注册，以便您可以接收 在您恢复此活动时广播。