声明权限
在新建项目中的AndroidManifest.xml中声明BLUETOOTH权限和BLUETOOTH_ADMIN权限:`
** 在文件res/values/strings.xml里,添加程序运行过程中的状态描述文本及配色代码**
蓝牙Demo
发送
你没有链接一个设备
蓝牙不可用,离开聊天室
链接中...
连接到:
无链接
蓝牙设备搜索中...
选择一个好友链接
没有配对好友
附近没有发现好友
已配对好友
其它可连接好友
搜索好友
我的好友
设置在线
退出
开始聊天
结束聊天
添加布局
在默认的主布局文件activity_main.xml里,添加1个Toolbar控件,其内包含2个水平的TextView控件;在Toolbar控件的下方添加1个ListView控件,用于显示聊天内容;最后在ListView控件的下方添加水平放置的1个EditText控件和一个Button控件。
编写蓝牙会话的服务组件ChatService
private static final String NAME = "BlueToothChat";
/** UUID*/
// UUID:通用唯一识别码,是一个128位长的数字,一般用十六进制表示
//算法的核心思想是结合机器的网卡、当地时间、一个随机数来生成
//再创建蓝牙连接
private static String strBlueTooth = "fa87c0d0-afac-11de-8a39-0800200c9a66";
private static final UUID MY_UUID = UUID.fromString(strBlueTooth);
private final BluetoothAdapter mAdapter;
/** 线程中通信的更新UI的Handler*/
private final Handler mHandler;
private AcceptThread mAcceptThread;
/** 监听到有客户端连接,新建一个线程单独处理,不然在此线程中会堵塞*/
private ConnectedThread mConnectedThread;
private ConnectThread mConnectThread;
private int mState;
mAdapter = BluetoothAdapter.getDefaultAdapter();
//获取蓝牙适配器
内部类
// 创建监听线程,准备接受新连接。使用阻塞方式,调用 BluetoothServerSocket.accept()
private class AcceptThread extends Thread {
private final BluetoothServerSocket mmServerSocket;
public AcceptThread() {
BluetoothServerSocket tmp = null;
try {
tmp = mAdapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
} catch (IOException e) {
e.printStackTrace();
}
mmServerSocket = tmp;
}
@Override
public void run() {
setName("AcceptThread");
BluetoothSocket socket = null;
while (mState != STATE_CONNECTED) {
try {
socket = mmServerSocket.accept();
} catch (IOException e) {
e.printStackTrace();
}
if (socket != null) {
synchronized (ChatService.this) {
switch (mState) {
case STATE_LISTEN:
case STATE_CONNECTING:
connected(socket, socket.getRemoteDevice());
break;
case STATE_NONE:
case STATE_CONNECTED:
try {
socket.close();
} catch (IOException e) {
e.printStackTrace();
}
break;
}
}
}
}
}
public void cancel() {
try {
mmServerSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/*
连接线程,专门用来对外发出连接对方蓝牙的请求和处理流程。
构造函数里通过 BluetoothDevice.createRfcommSocketToServiceRecord() ,
从待连接的 device 产生 BluetoothSocket. 然后在 run 方法中 connect ,
成功后调用 BluetoothChatSevice 的 connected() 方法。定义 cancel() 在关闭线程时能够关闭相关socket 。
*/
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
e.printStackTrace();
}
mmSocket = tmp;
}
@Override
public void run() {
setName("ConnectThread");
mAdapter.cancelDiscovery();
try {
mmSocket.connect();
} catch (IOException e) {
connectionFailed();
try {
mmSocket.close();
} catch (IOException ex) {
ex.printStackTrace();
}
ChatService.this.start();
return;
}
synchronized (ChatService.this) {
mConnectThread = null;
}
connected(mmSocket, mmDevice);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
```/*
双方蓝牙连接后一直运行的线程;构造函数中设置输入输出流。
run()方法中使用阻塞模式的 InputStream.read()循环读取输入流,然后发送到 UI 线程中更新聊天消息。
本线程也提供了 write() 将聊天消息写入输出流传输至对方,传输成功后回写入 UI 线程。最后使用cancel()关闭连接的 socket
*/
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;
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
@Override
public void run() {
byte[] buffer = new byte[1024];
int bytes;
while (true) {
try {
bytes = mmInStream.read(buffer);
mHandler.obtainMessage(weixinFragment.MESSAGE_READ, bytes, -1, buffer).sendToTarget();
} catch (IOException e) {
connectionLost();
break;
}
}
}
public void write(byte[] buffer) {
try {
mmOutStream.write(buffer);
mHandler.obtainMessage(weixinFragment.MESSAGE_WRITE, -1, -1, buffer).sendToTarget();
} catch (IOException e) {
e.printStackTrace();
}
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
Activity组件DeviceList,实现选取与之会话的蓝牙设备
经过选项菜单调用后可用于:显示已配对的好友列表;搜索可配对的好友进行配对;新选择并配的蓝牙设备将刷新好友列表。
public class DeviceList extends AppCompatActivity{
private BluetoothAdapter mBtAdapter;
private ArrayAdapter mPairedDevicesArrayAdapter;
private ArrayAdapter mNewDevicesArrayAdapter;
public static String EXTRA_DEVICE_ADDRESS = "device_address"; //Mac地址
//定义广播接收者,用于处理扫描蓝牙设备后的结果
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
if (device.getBondState() != BluetoothDevice.BOND_BONDED) {
mNewDevicesArrayAdapter.add(device.getName() + "\n" + device.getAddress());
}
} else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
if (mNewDevicesArrayAdapter.getCount() == 0) {
String noDevices = getResources().getText(R.string.none_found).toString();
mNewDevicesArrayAdapter.add(noDevices);
}
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.device_list);
//在被调用活动里,设置返回结果码
setResult(Activity.RESULT_CANCELED);
init(); //活动界面
}
private void init() {
Button scanButton = findViewById(R.id.button_scan);
scanButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Toast.makeText(DeviceList.this, R.string.scanning, Toast.LENGTH_LONG).show();
doDiscovery(); //搜索蓝牙设备
}
});
mPairedDevicesArrayAdapter = new ArrayAdapter(this, R.layout.device_name);
mNewDevicesArrayAdapter = new ArrayAdapter(this, R.layout.device_name);
//已配对蓝牙设备列表
ListView pairedListView =findViewById(R.id.paired_devices);
pairedListView.setAdapter(mPairedDevicesArrayAdapter);
pairedListView.setOnItemClickListener(mPaireDeviceClickListener);
//未配对蓝牙设备列表
ListView newDevicesListView = findViewById(R.id.new_devices);
newDevicesListView.setAdapter(mNewDevicesArrayAdapter);
newDevicesListView.setOnItemClickListener(mNewDeviceClickListener);
//动态注册广播接收者
IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);
registerReceiver(mReceiver, filter);
filter = new IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);
registerReceiver(mReceiver, filter);
mBtAdapter = BluetoothAdapter.getDefaultAdapter();
Set pairedDevices = mBtAdapter.getBondedDevices();
if (pairedDevices.size() > 0) {
findViewById(R.id.title_paired_devices).setVisibility(View.VISIBLE);
for (BluetoothDevice device : pairedDevices) {
mPairedDevicesArrayAdapter.add(device.getName() + "\n" + device.getAddress());
}
} else {
String noDevices = getResources().getText(R.string.none_paired).toString();
mPairedDevicesArrayAdapter.add(noDevices);
}
}
@Override
protected void onDestroy() {
super.onDestroy();
if (mBtAdapter != null) {
mBtAdapter.cancelDiscovery();
}
this.unregisterReceiver(mReceiver);
}
private void doDiscovery() {
findViewById(R.id.title_new_devices).setVisibility(View.VISIBLE);
if (mBtAdapter.isDiscovering()) {
mBtAdapter.cancelDiscovery();
}
mBtAdapter.startDiscovery(); //开始搜索蓝牙设备并产生广播
//startDiscovery是一个异步方法
//找到一个设备时就发送一个BluetoothDevice.ACTION_FOUND的广播
}
private OnItemClickListener mPaireDeviceClickListener = new OnItemClickListener() {
public void onItemClick(AdapterView> av, View v, int arg2, long arg3) {
mBtAdapter.cancelDiscovery();
String info = ((TextView) v).getText().toString();
String address = info.substring(info.length() - 17);
Intent intent = new Intent();
intent.putExtra(EXTRA_DEVICE_ADDRESS, address); //Mac地址
setResult(Activity.RESULT_OK, intent);
finish();
}
};
private OnItemClickListener mNewDeviceClickListener = new OnItemClickListener() {
public void onItemClick(AdapterView> av, View v, int arg2, long arg3) {
mBtAdapter.cancelDiscovery();
Toast.makeText(DeviceList.this, "请在蓝牙设置界面手动连接设备",Toast.LENGTH_SHORT).show();
Intent intent = new Intent(Settings.ACTION_BLUETOOTH_SETTINGS);
startActivityForResult(intent,1);
}
};
//回调方法:进入蓝牙配对设置界面返回后执行
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
init(); //刷新好友列表
}
}
实现蓝牙通信功能的Fragment
@Override
public synchronized void onResume() {
//synchronized:同步方法实现排队调用
super.onResume();
if (mChatService != null) {
if (mChatService.getState() == ChatService.STATE_NONE) {
mChatService.start();
}
}
}
private void setupChat() {
mConversationArrayAdapter = new ArrayAdapter(view.getContext(), R.layout.message);
mConversationView = view.findViewById(R.id.in);
mConversationView.setAdapter(mConversationArrayAdapter);
mOutEditText = view.findViewById(R.id.edit_text_out);
mOutEditText.setOnEditorActionListener(mWriteListener);
mSendButton = view.findViewById(R.id.button_send);
mSendButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
TextView textView = view.findViewById(R.id.edit_text_out);
String message = textView.getText().toString();
sendMessage(message);
}
});
//创建服务对象
mChatService = new ChatService(view.getContext(), mHandler);
mOutStringBuffer = new StringBuffer("");
}
@Override
public void onDestroy() {
super.onDestroy();
if (mChatService != null)
mChatService.stop();
}
private void ensureDiscoverable() { //修改本机蓝牙设备的可见性
//打开手机蓝牙后,能被其它蓝牙设备扫描到的时间不是永久的
if (mBluetoothAdapter.getScanMode() != BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE) {
Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
//设置在300秒内可见(能被扫描)
discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
startActivity(discoverableIntent);
Toast.makeText(view.getContext(), "已经设置本机蓝牙设备的可见性,对方可搜索了。", Toast.LENGTH_SHORT).show();
}
}
//使用Handler对象在UI主线程与子线程之间传递消息
private final Handler mHandler = new Handler() { //消息处理
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_STATE_CHANGE:
switch (msg.arg1) {
case ChatService.STATE_CONNECTED:
mTitle.setText(R.string.title_connected_to);
mTitle.append(mConnectedDeviceName);
mConversationArrayAdapter.clear();
break;
case ChatService.STATE_CONNECTING:
mTitle.setText(R.string.title_connecting);
break;
case ChatService.STATE_LISTEN:
case ChatService.STATE_NONE:
mTitle.setText(R.string.title_not_connected);
break;
}
break;
case MESSAGE_WRITE:
byte[] writeBuf = (byte[]) msg.obj;
String writeMessage = new String(writeBuf);
mConversationArrayAdapter.add("我: " + writeMessage);
break;
case MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
String readMessage = new String(readBuf, 0, msg.arg1);
mConversationArrayAdapter.add(mConnectedDeviceName + ": "
+ readMessage);
break;
case MESSAGE_DEVICE_NAME:
mConnectedDeviceName = msg.getData().getString(DEVICE_NAME);
Toast.makeText(getActivity().getApplicationContext(),"链接到 " + mConnectedDeviceName, Toast.LENGTH_SHORT).show();
break;
case MESSAGE_TOAST:
Toast.makeText(getActivity().getApplicationContext(), msg.getData().getString(TOAST), Toast.LENGTH_SHORT).show();
break;
}
}
};
源码地址:蓝牙通讯
参考文档 :Android近距离通信