我是Android开发的新手，并且一直在运行4.2.2的平板电脑上使用蓝牙通信。我希望接收从蓝牙模块发送到平板电脑的数据。我非常了解如何通过Android网站设置蓝牙套接字，但是我需要帮助接收传入的串行数据。使用下面的代码，我能够找到模块，打开套接字连接并连接到它（如模块上的绿灯所示），但是我需要帮助通过TextView在UI上显示传输的数据。该模块每秒以9600波特发送2个字节的数据。我的理解是run（）读取2个字节的数据并将其存储在缓冲区中。然后将这些字节传递给处理程序，该处理程序通过“case MESSAGE_READ;”在屏幕上显示它。有人可以让我知道我做错了什么吗？
package com.example.bluetoothtest;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Set;
import java.util.UUID;
import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity implements OnItemClickListener {
TextView mTextView;
ArrayAdapter<String> listAdapter;
ListView listView;
BluetoothAdapter btAdapter;
Set<BluetoothDevice> devicesArray;
ArrayList<String> pairedDevices;
ArrayList<BluetoothDevice> devices;
public static final UUID MY_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
protected static final int SUCCESS_CONNECT = 0;
protected static final int MESSAGE_READ = 1;
IntentFilter filter;
BroadcastReceiver receiver;
String tag = "debugging";
Handler mHandler = new Handler(){
@Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
Log.i(tag, "in handler");
super.handleMessage(msg);
switch(msg.what){
case SUCCESS_CONNECT:
ConnectedThread connectedThread = new ConnectedThread((BluetoothSocket)msg.obj);
Toast.makeText(getApplicationContext(), "CONNECT", 0).show();
String s = "successfully connected";
connectedThread.write(s.getBytes());
Log.i(tag, "connected");
break;
case MESSAGE_READ:
String str = (String)msg.obj;
mTextView.setText(str);
}
super.handleMessage(msg);
}
};
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextView=(TextView)findViewById(R.id.txtData);
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());
}
}
}
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>();
filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
devices = new ArrayList<BluetoothDevice>();
receiver = new BroadcastReceiver(){
@Override
public void onReceive(Context context, Intent intent) {
// TODO Auto-generated method stub
String action = intent.getAction();
if(BluetoothDevice.ACTION_FOUND.equals(action)){
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
devices.add(device);
String s = "";
for(int a = 0; a < pairedDevices.size(); a++){
if(device.getName().equals(pairedDevices.get(a))){
//append
s = "(Paired)";
break;
}
}
listAdapter.add(device.getName()+" "+s+" "+"\n"+device.getAddress());
}
else if(BluetoothAdapter.ACTION_DISCOVERY_STARTED.equals(action)){
}
else if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){
}
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 to continue", Toast.LENGTH_SHORT).show();
finish();
}
}
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
// TODO Auto-generated method stub
if(btAdapter.isDiscovering()){
btAdapter.cancelDiscovery();
}
if(listAdapter.getItem(arg2).contains("Paired")){
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;
Log.i(tag, "construct");
// 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) {
Log.i(tag, "get socket failed");
}
mmSocket = tmp;
}
public void run() {
// Cancel discovery because it will slow down the connection
btAdapter.cancelDiscovery();
Log.i(tag, "connect - run");
try {
// Connect the device through the socket. This will block
// until it succeeds or throws an exception
mmSocket.connect();
Log.i(tag, "connect - succeeded");
} catch (IOException connectException) { Log.i(tag, "connect failed");
// 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;
Log.i(tag, "socket connect success");
// Get the input and output streams, using temp objects because
// member streams are final
try {
tmpIn = socket.getInputStream();
Log.i(tag, "socket success");
tmpOut = socket.getOutputStream();
} catch (IOException e) { }
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
Log.i(tag, "run success");
byte[] buffer = new byte[2];
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);
Log.i(tag, "buffer read OK");
// Send the obtained bytes to the UI activity
String str = new String(buffer);
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, str).sendToTarget();
}catch (Exception e) {
Log.i(tag, "buffer read failed");
System.out.print("read error");
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)
尝试：
案例SUCCESS_CONNECT：
ConnectedThread connectedThread = new ConnectedThread((BluetoothSocket)msg.obj);
Toast.makeText(getApplicationContext(), "CONNECT", 0).show();
String s = "successfully connected";
connectedThread.write(s.getBytes());
Log.i(tag, "connected");
connectedThread.run();
break;
答案 1 :(得分：0)
实际上，您应该拨打connectedThread.start()，而不是connectedThread.run()。 start()方法导致connectedThread在单独的帖子上执行run()方法，如果您直接调用run()，建议如上，那么只有run()方法（这通常是一个无限循环，将阻止所有其他代码，包括UI线程。