Android-蓝牙:蓝牙服务行为异常 [英] Android- Bluetooth: Bluetooth Service behaving unexpectedly
问题描述
我正在编写一个可以与arduino交互的android应用.我的应用程序有2个按钮1.连接2.断开连接，以启动和停止蓝牙服务.我在arduino上有一个测试草图，当收到"1"时，会将"404"(只是为了测试！)发送回我的手机.
I am writing an android app that can interact with arduino. My app have 2 buttons 1. Connect 2. Dis-Connect, to start and stop bluetooth service. I have a test sketch on arduino which when receives "1" will send "404"(just to test!) back to my phone.
这是我的蓝牙服务课程
public class BluetoothService extends Service {
private BluetoothManager bluetoothManager;
private ServiceHandler mSHandler;
public BluetoothService(){}
private final class ServiceHandler extends Handler {
public ServiceHandler(Looper looper) {
super(looper);
}
@Override
public void handleMessage(Message msg) {
}
}
@Override
public void onCreate() {
super.onCreate();
HandlerThread thread = new HandlerThread("ServiceStartArguments", android.os.Process.THREAD_PRIORITY_BACKGROUND);
thread.start();
Looper mSLoop = thread.getLooper();
mSHandler = new ServiceHandler(mSLoop);
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Message msg = mSHandler.obtainMessage();
msg.arg1 = startId;
mSHandler.sendMessage(msg);
bluetoothManager=new BluetoothManager();
bluetoothManager.writeData("1", getApplicationContext()); //sending "1" to arduino
String str= bluetoothManager.readData(getApplicationContext()); //reading "404" from arduino
Toast.makeText(getApplicationContext(), str, Toast.LENGTH_LONG).show();
return START_STICKY;
}
@Override
public void onDestroy(){
bluetoothManager.turnBluetoothOff();
}
@Override
public IBinder onBind(Intent intent) {
return null;
}
}
现在这是我的BluetoothManager类:
Now here's my BluetoothManager class:
public class BluetoothManager {
private BluetoothAdapter bluetoothAdapter;
private BluetoothDevice bluetoothDevice;
private BluetoothSocket bluetoothSocket;
private ConnectedThread connectedThread;
private byte[] buffer;
public BluetoothManager(){
buffer=new byte[256];
bluetoothSocket=null;
bluetoothAdapter=null;
bluetoothDevice=null;
connectedThread=null;
getBluetoothAdapter();
if(!isBluetoothAvailable()){
turnBluetoothOn();
}
scanToConnect();
}
public void turnBluetoothOff(){
try {
bluetoothSocket.close();
bluetoothSocket=null;
bluetoothAdapter.cancelDiscovery();
bluetoothAdapter.disable();
bluetoothAdapter=null;
bluetoothDevice=null;
}catch(Exception e){
e.printStackTrace();
}
}
private boolean isBluetoothAvailable(){
return bluetoothAdapter.isEnabled();
}
private void turnBluetoothOn(){
bluetoothAdapter.enable();
}
public String readData(Context context){
String outputString=null;
if(isBluetoothAvailable()) {
outputString = connectedThread.read(buffer);
}else{
Toast.makeText(context, "Error: Not Connected", Toast.LENGTH_LONG).show();
}
return outputString;
}
public void writeData(String string, Context context){
if(isBluetoothAvailable()) {
connectedThread.write(string.getBytes());
}else{
Toast.makeText(context, "Error: Not Connected", Toast.LENGTH_LONG).show();
}
}
private void getBluetoothAdapter(){
try{
bluetoothAdapter=BluetoothAdapter.getDefaultAdapter();
}catch (Exception e){
e.printStackTrace();
}
}
private void scanToConnect(){
Set<BluetoothDevice> pairedDevices=bluetoothAdapter.getBondedDevices();
if(pairedDevices.size()>0){
try {
for (BluetoothDevice device : pairedDevices) {
if (device.getName().equals("HC-05")) {
bluetoothDevice = device;
new connectBt(bluetoothDevice);
break;
}
}
}catch(Exception e){
e.printStackTrace();
}
}
}
private class connectBt extends Thread {
public connectBt(BluetoothDevice device) {
BluetoothSocket tmp = null;
bluetoothDevice = device;
UUID uuid = UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");
try {
tmp = device.createRfcommSocketToServiceRecord(uuid);
} catch (IOException e) {
e.printStackTrace();
}
bluetoothSocket = tmp;
run();
}
public void run() {
bluetoothAdapter.cancelDiscovery();
try {
bluetoothSocket.connect();
connectedThread = new ConnectedThread(bluetoothSocket);
} catch (IOException connectException) {
closeSocket();
}
}
private void closeSocket() {
try {
bluetoothSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
private class ConnectedThread extends Thread{
private InputStream mInput=null;
private OutputStream mOutput=null;
private String strInput;
public ConnectedThread(BluetoothSocket socket){
bluetoothSocket=socket;
InputStream tmpIn=null;
OutputStream tmpOut=null;
try{
tmpIn=socket.getInputStream();
tmpOut=socket.getOutputStream();
}catch(IOException e){
e.printStackTrace();
closeSocket();
}
mInput=tmpIn;
mOutput=tmpOut;
}
public void write(byte[] bytes){
try{
mOutput.write(bytes);
}catch(IOException e){
e.printStackTrace();
}
}
public String read(byte[] bytes){
try {
mInput.read(bytes);
strInput = new String(bytes);
}catch(Exception e){
e.printStackTrace();
}
return strInput;
}
public void closeSocket(){
try{
bluetoothSocket.close();
}catch(IOException e){
e.printStackTrace();
}
}
}
}
我的问题是我必须按下两次连接按钮才能连接到arduino，第一次按下将启用蓝牙，第二次按下将连接到arduino，然后发送和接收数据.但这不是我想要的，启用蓝牙和连接应该只需要按一下就可以了. 那为什么会这样呢?
My problem is that I am have to press connect button twice to connect to arduino, first press will enable bluetooth and second press will connect to arduino, then send and receive data. But this is not as I intended, enabling bluetooth and connecting should have taken place with a single press. So why is this behaving like this?
N.B:我是Java和android的新手.
N.B: I am newbie to java and android.
推荐答案
启用蓝牙后，需要一段时间才能获取配对的设备列表.但是在这种情况下，打开蓝牙后，您将立即读取配对的设备.可能是您延迟了连接部分.
After enabling Bluetooth it will take sometime to get the paired device list. But in this case you are reading the paired devices immediately after turning on the Bluetooth. May be you delay the connection part.
使用处理程序方法延迟执行.
Use handler methods to delay the execution.
这篇关于Android-蓝牙:蓝牙服务行为异常的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
