关于andrion(安卓) 蓝牙(经典蓝牙)客户端连接

前言

这两天在开发一个android版的手机蓝牙通信的的APP,对android的蓝牙机进行了一个简单的研究

android上的蓝牙分为两种经典蓝牙(BR/EDR)和低功耗蓝牙(BLE)

因为我开发的是经典蓝牙开发的这里就简单讲下如何开发

开发前建议大家先去看下谷歌官方的蓝牙说明

https://developer.android.google.cn/guide/topics/connectivity/bluetooth

经典蓝牙

第一步申请权限

<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" /> <!-- 仅在支持BLE(即蓝牙4.0)的设备上运行 -->
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> <!-- 如果Android 6.0蓝牙搜索不到设备，需要补充下面两个权限 -->
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BLUETOOTH" /> <!-- 网络权限 -->

大概要申请这么多权限

这里发起前要注意下,android 9以后,关键性权限需要用户第二次确认才能调用,所以这个发起搜索肯定是写在权限回调里面的

//申请用户权限
ActivityCompat.requestPermissions(MainActivity.this, mPermissionListnew, mOpenCode);

第二歩发起搜索

获取当前蓝牙管理器

 mBluetooth = BluetoothAdapter.getDefaultAdapter();

判断当前蓝牙是否启动

  //蓝牙服务未启动if (!mBluetooth.isEnabled()) {boolean enable = mBluetooth.enable();if (!enable) {SystemExit(getString(R.string.initBluetooth));return;}}

下面是完整代码

// 权限回调
@Override
@SuppressLint("MissingPermission")
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,@NonNull int[] grantResults) {super.onRequestPermissionsResult(requestCode, permissions, grantResults);//判断权限是否同意 这里要注意下,每个安卓版本的权限是不一样的for (Integer permission : grantResults) {if (permission != 0) {SystemExit(getString(R.string.run));return;}}//从系统服务中获取蓝牙管理器//这里虽然写了很多,但是BluetoothAdapter.getDefaultAdapter() 这个就可以的if (mBluetooth == null) {if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {//从系统服务中获取蓝牙管理器BluetoothManager bm = getSystemService(BluetoothManager.class);mBluetooth = bm.getAdapter();} else {//获取系统默认的蓝牙适配器mBluetooth = BluetoothAdapter.getDefaultAdapter();}if (mBluetooth == null) {SystemExit("没有蓝牙功能");return;}}//蓝牙服务未启动if (!mBluetooth.isEnabled()) {boolean enable = mBluetooth.enable();if (!enable) {SystemExit(getString(R.string.initBluetooth));return;}}if (requestCode == mOpenCode) {//初始化蓝牙initBluetooth();}
}

上面写了那么多其实本质上还是在申请权限那一批里面

下面开始进行蓝牙扫描

也就是上面initBluetooth()方法

开启蓝牙扫描

开启蓝牙扫很简单调用下startDiscovery()方法就行

@SuppressLint("MissingPermission")
private void beginDiscovery() {if (mBluetooth != null && !mBluetooth.isDiscovering()) {mBluetooth.startDiscovery();//开始扫描周围的蓝牙设备}
}

获取蓝牙扫描的返回数据

获取蓝牙扫描数据,就要先注册广播,通过广播回调进行获取数据

//需要过滤多个动作，则调用IntentFilter对象的addAction添加新动作
IntentFilter discoveryFilter = new IntentFilter();
//获取新的数据
discoveryFilter.addAction(BluetoothDevice.ACTION_FOUND);
//连接上了
discoveryFilter.addAction(BluetoothDevice.ACTION_ACL_CONNECTED);
//状态改变
discoveryFilter.addAction(BluetoothDevice.ACTION_BOND_STATE_CHANGED);
//蓝牙连接状态更改
discoveryFilter.addAction(BluetoothDevice.ACTION_ACL_DISCONNECTED);
//蓝牙即将断开
discoveryFilter.addAction(BluetoothDevice.ACTION_ACL_DISCONNECT_REQUESTED);
//注册蓝牙设备搜索的广播接收器 discoveryReceiver()这个是回调函数
registerReceiver(discoveryReceiver, discoveryFilter);

回调方法

@SuppressLint("MissingPermission")public final BroadcastReceiver discoveryReceiver = new BroadcastReceiver() {@RequiresApi(api = Build.VERSION_CODES.R)@SuppressLint("NotifyDataSetChanged")@Overridepublic void onReceive(Context context, Intent intent) {String action = intent.getAction();BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);int bondState = device.getBondState();Fruit fruit = new Fruit();fruit.setAddress(device.getAddress());//发现新的蓝牙设备fruit.setName(device.getName());if (fruit.getName() == null || fruit.getName().length() == 0) {fruit.setName("N/A");}fruit.setState(bondState);fruit.setBluetoothType(device.getType());short rssi = intent.getExtras().getShort(BluetoothDevice.EXTRA_RSSI);fruit.setRssi(rssi + "");fruit.setBluetoothDevice(device);onActivityDataChangedListener.addFruitData(fruit);switch (action) {case BluetoothDevice.ACTION_FOUND:break;//蓝牙状态修改//断开蓝牙连接case BluetoothDevice.ACTION_ACL_DISCONNECTED:case BluetoothDevice.ACTION_ACL_DISCONNECT_REQUESTED:BluetoothServiceConnect remove = StaticObject.bluetoothSocketMap.remove(device.getAddress());if (remove != null) {ToastUtil.toastWord(MainActivity.this, MainActivity.this.getString(ConnectTheInterrupt));remove.close();Msg m = new Msg(device.getAddress());m.setStateType(1);try {StaticObject.mTaskQueue.put(m);} catch (InterruptedException e) {e.printStackTrace();}}//蓝牙状态修改case BluetoothDevice.ACTION_ACL_CONNECTED:case BluetoothDevice.ACTION_BOND_STATE_CHANGED:
/*                    fruit.setState(bondState);short rssi = intent.getExtras().getShort(BluetoothDevice.EXTRA_RSSI);fruit.setRssi(rssi + "");onActivityDataChangedListener.addFruitData(fruit);*///adapter.notifyDataSetChanged();break;}}};

另外说下通过**getBondedDevices()**这个方法可以获取已经配对了蓝牙信息

Set<BluetoothDevice> bondedDevices = mBluetooth.getBondedDevices();if (bondedDevices != null && bondedDevices.size() != 0) {for (BluetoothDevice device : bondedDevices) {Fruit fruit = new Fruit();fruit.setAddress(device.getAddress());fruit.setName(device.getName());fruit.setState(device.getBondState());fruit.setBluetoothType(device.getType());fruit.setBluetoothDevice(device);onActivityDataChangedListener.addFruitData(fruit);}
}

连接蓝牙

上面已经获取了蓝牙驱动,接下来就是连接蓝牙了,这一步比较简单

通过方法回调获取BluetoothDevice 对象,调用createInsecureRfcommSocketToServiceRecord()这个方法,传入uuid来获取socker连接

uuid说明https://note.youdao.com/s/QLLkD2ZA

    static final String SPP_UUID = "00001101-0000-1000-8000-00805F9B34FB";BluetoothSocket insecureRfcommSocketToServiceRecord= bluetoothDevice.createInsecureRfcommSocketToServiceRecord(UUID.fromString(SPP_UUID));
insecureRfcommSocketToServiceRecord.connect();
//然后这里就获取到输入流和输出流,接下来就可以进行交互了
insecureRfcommSocketToServiceRecord.getOutputStream()
insecureRfcommSocketToServiceRecord.getInputStream()