最近課上剛好需要做一個課程設(shè)計關(guān)于藍牙的就挑選了個藍牙聊天室，其實關(guān)鍵還是在于對藍牙API的了解
一.藍牙API
與藍牙開發(fā)主要的相關(guān)類是以下四個
- BluetoothAdapter
字面上則理解為藍牙適配器，打開藍牙，關(guān)閉藍牙，搜索設(shè)備，獲取藍牙Socket連接都是通過這個類來實現(xiàn)的。對應(yīng)的方法就有- enable()：用來打開藍牙，一般在5.0后的話則會出現(xiàn)彈框提示是否開啟藍牙，其他則沒有提示，也可以調(diào)用來進行彈窗打開
Intent intent =new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivity(intent );
disable()：關(guān)閉藍牙
getDefaultAdapter()：獲取藍牙適配器BluetoothAdapter，只有這個方法來獲取
getAddress()：獲取本地藍牙的MAC地址，這個則是每一個藍牙設(shè)備的唯一
getName()：獲取本地藍牙的名稱
getRemoteDevice(String address)：獲取藍牙地址獲取到遠(yuǎn)程的設(shè)備
startDiscovery()：開啟藍牙設(shè)備搜索
cancelDiscovery()：關(guān)閉掃描
listenUsingRfcommWithServiceRecord(serverSocketName,UUID)：獲取BluetoothServerSocket
-
BluetoothDevice
代表一個藍牙設(shè)備createRfcommSocketToServiceRecord(UUIDuuid)：根據(jù)UUID創(chuàng)建并返回一個BluetoothSocket
getName()：獲取藍牙設(shè)備名稱
getAddress()：獲取藍牙的MAC地址
BluetoothServerSocket：類似于ServerSocket，方法都差不多，可以說藍牙之間的通訊跟Socket相似。這個相當(dāng)于服務(wù)器Socket
accept()：這個方法會阻塞，直到連接建立，用來監(jiān)聽連接
close()：關(guān)閉socket連接
-
BluetoothSocket：相當(dāng)于客戶端Socket
connect()：用來向服務(wù)器BluetoothServerSocket發(fā)起連接
getInputStream()：獲取輸入流
getOutputStream()：獲取輸出流
close()：關(guān)閉連接
getRemoteDevice()：獲取這個Socket連接的遠(yuǎn)程設(shè)備
二.搜索藍牙設(shè)備
知道對應(yīng)API后就可以進行對應(yīng)的藍牙開發(fā)，這里以獲取藍牙設(shè)備為例子
1.獲取本地藍牙適配器
BluetoothAdapter
mAdapter= BluetoothAdapter.getDefaultAdapter();
2.打開藍牙
if(!mAdapter.isEnabled()){
//彈出對話框提示用戶是后打開
Intent enabler = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(enabler, REQUEST_ENABLE);
//不做提示，強行打開
// mAdapter.enable();
}
3.搜索設(shè)備
mAdapter.startDiscovery(); //開啟搜索
搜索設(shè)備的回調(diào)則需要通過注冊廣播的形式來獲取
//發(fā)現(xiàn)設(shè)備的Action
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
registerReceiver(mReceiver, filter);
//設(shè)備搜索完畢的action
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
registerReceiver(mReceiver, filter);
定義廣播
BroadcastReceiver mReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
//當(dāng)掃描到設(shè)備的時候
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
// 獲取設(shè)備對象
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
//提取強度信息
int rssi = intent.getExtras().getShort(BluetoothDevice.EXTRA_RSSI);
Log.e(TAG, device.getName() + "\n" + device.getAddress() + "\n強度：" + rssi);
} //搜索完成
else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
Log.e(TAG, "onReceive: 搜索完成" );
}
}
};
之后就可以進行個人的一些操作
三.藍牙聊天的實現(xiàn)
要實現(xiàn)藍牙聊天則涉及到藍牙之間的傳輸通信，前面也說到了，這里肯定就是用到BluetoothServerSocket以及BluetoothSocket。
藍牙傳輸通信相當(dāng)于服務(wù)器端與客戶端之間的通信，只不過不同是這里每一個藍牙設(shè)備本身自己既充當(dāng)服務(wù)器端也充當(dāng)客戶端，大致的關(guān)系就是
注意，這些連接都是阻塞式的，都要放在線程里去執(zhí)行。
1.對于BluetoothServerSocket，建立一個AcceptThread，來監(jiān)聽是否有設(shè)備發(fā)起連接
//連接等待線程
class AcceptThread extends Thread{
private final BluetoothServerSocket serverSocket;
public AcceptThread(){
BluetoothServerSocket tmp = null;
try {
//獲取實例
tmp = bluetoothAdapter.listenUsingRfcommWithServiceRecord(NAME_SECURE, MY_UUID_SECURE);
} catch (IOException e) {
e.printStackTrace();
}
serverSocket = tmp;
}
@Override
public void run() {
super.run();
//監(jiān)聽是否有端口連接
BluetoothSocket socket = null;
while(mState != STATE_TRANSFER) {
try {
Log.e(TAG, "run: AcceptThread 阻塞調(diào)用，等待連接");
socket = serverSocket.accept();
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "run: ActivityThread fail");
break;
}
//獲取到連接Socket后則開始通信
if(socket != null){
synchronized (BluetoothChatService.this) {
switch (mState) {
case STATE_LISTEN:
case STATE_CONNECTING:
//傳輸數(shù)據(jù)，服務(wù)器端調(diào)用
Log.e(TAG, "run: 服務(wù)器AcceptThread傳輸" );
sendMessageToUi(MainActivity.BLUE_TOOTH_DIALOG , "正在與" + socket.getRemoteDevice().getName() + "連接");
//開始數(shù)據(jù)傳輸
dataTransfer(socket, socket.getRemoteDevice());
break;
case STATE_NONE:
case STATE_TRANSFER:
// 沒有準(zhǔn)備好或者終止連接
try {
socket.close();
} catch (IOException e) {
Log.e(TAG, "Could not close unwanted socket" + e);
}
break;
}
}
}
}
}
public void cancel(){
Log.e(TAG, "close: activity Thread" );
try {
if(serverSocket != null)
serverSocket.close();
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "close: activity Thread fail");
}
}
}
可以看到，當(dāng)BluetoothServerSocket監(jiān)聽到有設(shè)備連接的時候，就會調(diào)用dataTransfer開啟一個數(shù)據(jù)傳輸。
2.同樣如何發(fā)起連接BluetoothSocket呢
需要一個ConnectThread來發(fā)起
class ConnectThread extends Thread{
private final BluetoothSocket socket;
private final BluetoothDevice device;
public ConnectThread(BluetoothDevice device) {
this.device = device;
BluetoothSocket mSocket = null;
try {
//獲取Socket
mSocket = device.createRfcommSocketToServiceRecord(
MY_UUID_SECURE);
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "ConnectThread: fail" );
sendMessageToUi(MainActivity.BLUE_TOOTH_TOAST , "連接失敗，請重新連接");
}
socket = mSocket;
}
@Override
public void run() {
super.run();
//建立后取消掃描
bluetoothAdapter.cancelDiscovery();
try {
//開啟連接
socket.connect();
} catch (IOException e) {
e.printStackTrace();
try {
socket.close();
} catch (IOException e1) {
e1.printStackTrace();
Log.e(TAG, "run: unable to close" );
}
//TODO 連接失敗顯示
sendMessageToUi(MainActivity.BLUE_TOOTH_TOAST , "連接失敗，請重新連接");
BluetoothChatService.this.start();
}
// 重置
synchronized (BluetoothChatService.this) {
mConnectThread = null;
}
//連接建立，開始傳輸
dataTransfer(socket, device);
}
public void cancel(){
try {
if(socket != null)
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
之后建立連接之后就會調(diào)用dataTransfer來進行數(shù)據(jù)傳輸，同樣也需要一個線程來維護數(shù)據(jù)傳輸
class TransferThread extends Thread{
private final BluetoothSocket socket;
private final OutputStream out;
private final InputStream in;
public TransferThread(BluetoothSocket mBluetoothSocket){
socket = mBluetoothSocket;
OutputStream mOutputStream = null;
InputStream mInputStream = null;
try {
if(socket != null){
//獲取連接的輸入輸出流
mOutputStream = socket.getOutputStream();
mInputStream = socket.getInputStream();
}
} catch (IOException e) {
e.printStackTrace();
}
out = mOutputStream;
in = mInputStream;
isTransferError = false;
}
@Override
public void run() {
super.run();
//讀取數(shù)據(jù)
byte[] buffer = new byte[1024];
int bytes;
while (true){
try {
bytes = in.read(buffer);
//TODO 分發(fā)到主線程顯示
uiHandler.obtainMessage(MainActivity.BLUE_TOOTH_READ, bytes, -1, buffer)
.sendToTarget();
Log.e(TAG, "run: read " + new String(buffer , 0 , bytes) );
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "run: Transform error" + e.toString());
BluetoothChatService.this.start();
//TODO 連接丟失顯示并重新開始連接
sendMessageToUi(MainActivity.BLUE_TOOTH_TOAST , "設(shè)備連接失敗/傳輸關(guān)閉");
isTransferError = true;
break;
}
}
}
/**
* 寫入數(shù)據(jù)傳輸
* @param buffer
*/
public void write(byte[] buffer) {
try {
out.write(buffer);
//TODO 到到UI顯示
uiHandler.obtainMessage(MainActivity.BLUE_TOOTH_WRAITE , -1, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(TAG, "Exception during write " + e);
}
}
public void cancel() {
try {
if(socket != null)
socket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect socket failed" + e);
}
}
}
藍牙聊天則是基于上面三個線程來進行實現(xiàn)，同樣，對于藍牙文件間的傳輸也是同個道理，通過輸入輸出流來進行處理。之后的操作就比較容易處理了
