准备

1.蓝牙串行端口基于SPP协议(Serial Port Profile)，能在蓝牙设备之间创建串口进行数据传输

2.SPP的UUID：00001101-0000-1000-8000-00805F9B34FB

3.Android手机一般以客户端的角色主动连接SPP协议设备

连接流程

1.检测蓝牙状态

若蓝牙未打开，则打开蓝牙~bluetoothAdapter =BluetoothAdapter.getDefaultAdapter();

@Overrideprotected voidonResume() {super.onResume();if (!bluetoothAdapter.isEnabled()) {//open blueTooth

Intent enableBtIntent = newIntent( BluetoothAdapter.ACTION_REQUEST_ENABLE);

startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);

}

}

@Overrideprotected void onActivityResult(int requestCode, intresultCode, Intent data) {if (requestCode == REQUEST_ENABLE_BT && resultCode ==Activity.RESULT_CANCELED) {

finish();return;

}

}

2.注册设备搜索广播信息

使用registerReceiver注册broadcastReceiver来获取搜索设备等消息IntentFilter intentFilter = newIntentFilter();

intentFilter.addAction(BluetoothDevice.ACTION_FOUND);

intentFilter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);

registerReceiver(receiver, intentFilter);//receiver

private final BroadcastReceiver receiver = newBroadcastReceiver(){

@Overridepublic voidonReceive(Context context, Intent intent) {

String action=intent.getAction();if(BluetoothDevice.ACTION_FOUND.equals(action)) {//find a device

BluetoothDevice device =intent .getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);if (device.getBondState() !=BluetoothDevice.BOND_BONDED) {//未配对设备

newDeviceArrayAdapter.add(device.getName() + "\n" +device.getAddress());

}else{//已经配对过的设备

TextView tvPaired =(TextView)findViewById(R.id.tv_paired);

tvPaired.setVisibility(View.VISIBLE);

lvPairedDevices.setVisibility(View.VISIBLE);

pairedDeviceArrayAdapter.add(device.getName()+ "\n" +device.getAddress());

}

Log.i(TAG,"name:" + device.getName() + " address"+device.getAddress());

}else if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action){//search finish

Log.i(TAG, "search finish!");

}

}

};

3.使用BlueAdatper搜索

使用bluetoothAdapter搜索设备，bluetoothAdapter.startDiscovery()在搜索过程中，系统会发出三个广播信息:

ACTION_DISCOVERY_START：开始搜索

ACTION_DISCOVERY_FINISHED：搜索结束

ACTION_FOUND：找到设备@Overridepublic voidonClick(View v) {if(bluetoothAdapter.isDiscovering()) {

bluetoothAdapter.cancelDiscovery();

}

bluetoothAdapter.startDiscovery();

}

4.获取搜索到的蓝牙设备信息

在BroadcastReceiver的onReceive()里取得搜索到的蓝牙设备信息(如名称，MAC，RSSI)

5.通过蓝牙设备的MAC地址来建立一个BluetoothDevice对象：BluetoothDevice romoteDevice = bluetoothAdapter.getRemoteDevice(mDeviceAddress);

6.由BluetoothDevice衍生BluetoothSocket

通过BluetoothSocket的createRfcommSocketToServiceRecord()方法来选择连接的协议/服务，这里用的是SPP(UUID:00001101-0000-1000-8000-00805F9B34FB)try{

bluetoothSocket=romoteDevice.createRfcommSocketToServiceRecord(UUID.fromString(SPP_UUID));

}catch(IOException e) {

e.printStackTrace();

Toast.makeText(this, "socket init failed", Toast.LENGTH_SHORT).show();

}

7.使用BluetoothSocket来连接、读写蓝牙设备

读写可以归到一个独立线程去实现~try{

bluetoothSocket.connect();

Toast.makeText(this, "connect success", Toast.LENGTH_SHORT).show();

}catch(IOException e2) {

e2.printStackTrace();

Toast.makeText(this, "connect failed", Toast.LENGTH_SHORT).show();try{

bluetoothSocket.close();

bluetoothSocket= null;

}catch(IOException e) {

e.printStackTrace();

Toast.makeText(this, "socket close failed", Toast.LENGTH_SHORT).show();

}return;

}try{

inputStream=bluetoothSocket.getInputStream();

}catch(IOException e2) {

e2.printStackTrace();

Toast.makeText(this, "get inputstream failed", Toast.LENGTH_SHORT).show();return;

}try{

OutputStream os=bluetoothSocket.getOutputStream();byte[] osBytes =etInput.getText().toString().getBytes();for (int i = 0; i < osBytes.length; i++) {if (osBytes[i] == 0x0a)

n++;

}byte[] osBytesNew = new byte[osBytes.length+n];

n= 0;for (int i = 0; i < osBytesNew.length; i++) {//mobile "\n"is 0a,modify 0d 0a then send

if (osBytesNew[i] == 0x0a) {

osBytesNew[n]= 0x0d;

n++;

osBytesNew[n]= 0x0a;

}else{

osBytesNew[n]=osBytes[i];

}

n++;

}

os.write(osBytesNew);

}catch(Exception e) {

e.printStackTrace();

}