android BLE Peripheral 手机模拟设备发出BLE广播 BluetoothLeAdvertiser

android 从4.3系统开始可以连接BLE设备，这个大家都知道了。iOS是从7.0版本开始支持BLE。android 进入5.0时代时，开放了一个新功能，手机可以模拟设备发出BLE广播， 这个新功能其实是 对标于 iOS系统的手机模拟iBeacon设备。先介绍一下BLE的广播， BLE设备之所以能被手机扫描到，是因为 BLE设备一直在每隔 一段时间广播一次，这个广播里面包含很多数据。手机扫描BLE设备代码如下：public void startScan(){bluetoothAdapter.startLeScan(leScanCallback);}public void stopScan(){bluetoothAdapter.stopLeScan(leScanCallback);}private LeScanCallback leScanCallback=new LeScanCallback() {@Overridepublic void onLeScan(BluetoothDevice bluetoothdeivce, int rssi, byte[] scandata) {//把byte数组转成16进制字符串，方便查看Log.e("TAG","scandata:"+ CYUtils.Bytes2HexString(scandata));}};
ok，这段代码大家在做连接BLE设备进行通讯的时候，已经很熟悉了。其中的 byte数组 scandata就是 BLE设备的广播数据。那么接下来，我们开始使用 手机1 模拟成BLE设备来发送广播，然后用手机2 来进行扫描查看广播数据 scandata首先获取 BluetoothAdapter， 熟悉的代码：BluetoothManager bluetoothManager = (BluetoothManager)getSystemService(Context.BLUETOOTH_SERVICE);bluetoothAdapter = bluetoothManager.getAdapter();进行广播的时候需要用到BluetoothLeAdvertiser，进行实例化：mBluetoothLeAdvertiser = bluetoothAdapter.getBluetoothLeAdvertiser();
实例化好之后就可以进行广播数据了，开启广播方法是：BluetoothLeAdvertiser: 
public void startAdvertising(AdvertiseSettings settings,AdvertiseData advertiseData, final AdvertiseCallback callback)
其中， AdvertiseSettings 是广播的一些设置，比如，广播间隔，是否可以连接等等; AdvertiseData 就是广播数据了， AdvertiseCallback是广播回调，会告诉你广播成功还是失败。先给一段完整广播代码如下：public void startAction(View v){byte[] broadcastData ={0x34,0x56};mBluetoothLeAdvertiser.startAdvertising(createAdvSettings(true, 0), createAdvertiseData(broadcastData), mAdvertiseCallback);}public void stopAction(View v) {mBluetoothLeAdvertiser.stopAdvertising(mAdvertiseCallback);}public AdvertiseSettings createAdvSettings(boolean connectable, int timeoutMillis) {AdvertiseSettings.Builder mSettingsbuilder = new AdvertiseSettings.Builder();mSettingsbuilder.setAdvertiseMode(AdvertiseSettings.ADVERTISE_MODE_LOW_LATENCY);mSettingsbuilder.setConnectable(connectable);mSettingsbuilder.setTimeout(timeoutMillis);AdvertiseSettings mAdvertiseSettings = mSettingsbuilder.build();return mAdvertiseSettings;}public AdvertiseData createAdvertiseData(byte[] data) {AdvertiseData.Builder mDataBuilder = new AdvertiseData.Builder();mDataBuilder.addManufacturerData(0x01AC, data);AdvertiseData mAdvertiseData = mDataBuilder.build();return mAdvertiseData;}private AdvertiseCallback mAdvertiseCallback = new AdvertiseCallback() {@Overridepublic void onStartSuccess(AdvertiseSettings settingsInEffect) {super.onStartSuccess(settingsInEffect);ToastUtils.showToast(MainActivity.this, "开启广播成功", 2000);}@Overridepublic void onStartFailure(int errorCode) {super.onStartFailure(errorCode);ToastUtils.showToast(MainActivity.this, "开启广播失败 errorCode：" + errorCode, 2000);}};其中，广播数据broadcastData 我暂时直接先定死为2个字节 0x3456，同样在createAdvertiseData里面也有定死的数据 0x01AC . 开启成功之后我们使用手机2 来扫描看下广播的数据是什么：E/TAG: scandata:02011A05FFAC0134560000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
log打印出来的scandata 有效数据是 02011A05FFAC013456 .  给大家解释一下这个数据的意思为了看清楚，我分段如下： 02011A  05  FF AC01 3456   （注，这里的都是16进制数字）02011A这3个字节，02表示后面一段数据长度为2字节，01表示数据类型是flag ,1A就是flag的数据了05 表示后面的一段数据长度为 5个字节， FF一个字节，AC01 两个字节，3456两个字节，加起来一共5个字节，老铁没毛病FF，是一个数据类型，这是我们通过代码mDataBuilder.addManufacturerData(0x01AC, data); 添加广播数据时候设置的ManufacturerData 是指设备厂商自定义数据，FF 就是代表下面的数据实体是厂商数据.第一个参数0x01AC，是厂商id，id长度为2个字节，不足2个字节系统会补0，可以看到log打印出来的是 AC01，顺序是倒过来的，这点要注意！如果我代码是这样写的 ：mDataBuilder.addManufacturerData(0xAC, data); //只写了一个字节的id
那么使用手机2 扫描出的scandata是：E/TAG: scandata:02011A05FFAC0034560000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
可以看到，AC后面系统自动补了00广播数据出除了可以添加ManufacturerData，还可以添加ServerUUID, 代码如下：public AdvertiseData createAdvertiseData(byte[] data) {AdvertiseData.Builder mDataBuilder = new AdvertiseData.Builder();mDataBuilder.addManufacturerData(0x01AC, data);mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"));AdvertiseData mAdvertiseData = mDataBuilder.build();return mAdvertiseData;}
代码添加了一个 AE8F的 server uuid， 使用手机2 扫描的scandata 如下：E/TAG: scandata:02011A05FFAC01345603038FAE00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
直接看03038FAE 这一段，第一个03 表示后面的一段数据长度为3个字节  第二个03 表示这个数据类型是 server uuid类型，uuid的数据就是8FAE，顺序是倒过来的！有人会问： 如果 我把addServiceUuid代码放在 addManufacturerData 前面，扫描的数据顺序是什么样的呢？答案 还是：E/TAG: scandata:02011A05FFAC01345603038FAE00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
可以添加多个 server uuid吗？ 可以，代码如下：public AdvertiseData createAdvertiseData(byte[] data) {AdvertiseData.Builder mDataBuilder = new AdvertiseData.Builder();mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"));mDataBuilder.addManufacturerData(0x01AC, data);AdvertiseData mAdvertiseData = mDataBuilder.build();return mAdvertiseData;}
扫描的结果是：E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
直接看0503 8FAE E1FF 这一段， 05 表示后面的一段数据长度是5个字节，03表示数据类型是 server uuid， 8FAE是第一个uuid, E1FF是第二个uuid这个ServerUUID 有什么用呢？ 不知大家在扫描BLE设备的时候，有没有注意到这个方法：BluetoothAdapter
public boolean startLeScan(final UUID[] serviceUuids, final LeScanCallback callback)这个方法也可以用来扫描BLE设备，但是多了一个参数， UUID数组， 这个扫描方法是用来过滤BLE设备用的，比如 你公司开发一个 蓝牙防丢器APP，你使用 startLeScan(callback)这个方法扫描的话，你会发现你扫描到周围的所有的BLE设备，同事戴的小米手环可能也被你扫描到，这样让用户来选择设备进行连接的话可能就比较迷糊，startLeScan(serviceUuids,callback) 这个方法在扫描的时候会过滤广播里的数据，只有符合的BLE设备才会被扫描回调。 所以，你们公司的蓝牙防丢器设备可以在广播字段里加入特定的server uuid， app扫描的时候可以过滤其他设备。我们来实现一下这个功能， 修改 手机2 的扫描代码：public void startScan(){UUID[] serviceUuids = new UUID[] { UUID    .fromString("0000ae8f-0000-1000-8000-00805f9b34fb") };bluetoothAdapter.startLeScan(serviceUuids, leScanCallback);}public void stopScan(){bluetoothAdapter.stopLeScan(leScanCallback);}private LeScanCallback leScanCallback=new LeScanCallback() {@Overridepublic void onLeScan(BluetoothDevice bluetoothdeivce, int rssi, byte[] scandata) {//把byte数组转成16进制字符串，方便查看Log.e("TAG","scandata:"+ CYUtils.Bytes2HexString(scandata));}};
扫描结果是这样的：05-23 16:13:30.522 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:30.625 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:30.735 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:30.847 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:30.955 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:31.061 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:31.192 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:31.283 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:31.369 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
05-23 16:13:31.480 10197-10197/jiqi.blescandemo E/TAG: scandata:02011A05FFAC01345605038FAEE1FF0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
可以发现，扫描结果里面只会出现拥有  AE8F 这个uuid的 BLE设备，搜索不到其他设备注意：部分手机使用startLeScan(serviceUuids,callback)这个方法过滤设备 会扫描不到设备，即使这个设备UUID符合过滤条件，我归结为手机/系统问题，如三星手机这样，我们知道，广播数据可以添加ManufacturerData，还可以添加ServerUUID, 还有吗？ 有，代码如下：public AdvertiseData createAdvertiseData(byte[] data) {AdvertiseData.Builder mDataBuilder = new AdvertiseData.Builder();mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceData( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"),new byte[]{0x64,0x12});mDataBuilder.addManufacturerData(0x01AC, data);AdvertiseData mAdvertiseData = mDataBuilder.build();return mAdvertiseData;}扫描结果如下：E/TAG: scandata:02011A05FFAC01345605038FAEE1FF05168FAE64120000000000000000000000000000000000000000000000000000000000000000000000000000000000
直接看05168FAE6412 这一段，05依然表示下面一段数据长度为5个字节，16表示数据类型为 server data， 8FAE表示这个数据的uuid是AE8F， 6412就是数据本体了.那么这个 server data能做什么呢？比如有这样一个 产品：温度计，温度计硬件在广播字段里的server data里面加入它测量的温度，这样APP可以不连接温度计设备 只通过扫描就知道温度了，是不是很方便.以下有几个坑请大家注意一下：情况1：public AdvertiseData createAdvertiseData(byte[] data) {AdvertiseData.Builder mDataBuilder = new AdvertiseData.Builder();// mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceData( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"),new byte[]{0x64,0x12});mDataBuilder.addManufacturerData(0x01AC, data);AdvertiseData mAdvertiseData = mDataBuilder.build();return mAdvertiseData;}我注释了一句代码，广播字段里我没有 添加 ae8f这个 uuid，而直接添加了 ae8f的data 为 0x6412，那么扫描结果如何？使用startLeScan(serviceUuids,callback)过滤 ae8f这个uuid，没有扫描结果;使用startLeScan(callback),扫描结果如下：E/TAG: scandata:02011A05FFAC0134560303E1FF05168FAE641200000000000000000000000000000000000000000000000000000000000000000000000000000000000000可以看到是有 ae8f对应的数据 6412，但是server uuid里面是没有 ae8f的.情况2：代码顺序1：mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceData( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"),new byte[]{0x22,0x44});mDataBuilder.addServiceData( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"),new byte[]{0x54,0x12});//扫描结果
E/TAG: scandata:02011A05FFAC01345605038FAEE1FF05168FAE54120000000000000000000000000000000000000000000000000000000000000000000000000000000000代码顺序2：mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceData( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"),new byte[]{0x54,0x11});mDataBuilder.addServiceData( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"),new byte[]{0x22,0x43});//扫描结果
E/TAG: scandata:02011A05FFAC01345605038FAEE1FF05168FAE54110000000000000000000000000000000000000000000000000000000000000000000000000000000000代码顺序3：mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceData( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"),new byte[]{0x54,0x1A});mDataBuilder.addServiceData( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"),new byte[]{0x22,0x47});//扫描结果
E/TAG: scandata:02011A05FFAC0134560503E1FF8FAE05168FAE541A0000000000000000000000000000000000000000000000000000000000000000000000000000000000代码顺序4：mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceUuid( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"));mDataBuilder.addServiceData( ParcelUuid.fromString("0000ffe1-0000-1000-8000-00805f9b34fb"),new byte[]{0x22,0x48});mDataBuilder.addServiceData( ParcelUuid.fromString("0000ae8f-0000-1000-8000-00805f9b34fb"),new byte[]{0x54,0x1B});//扫描结果
E/TAG: scandata:02011A05FFAC0134560503E1FF8FAE05168FAE541B0000000000000000000000000000000000000000000000000000000000000000000000000000000000情况2总结：从上面4个代码顺序的结果来看，总是扫描到 ae8f这个uuid对应的数据，没有第二个 server data，但是为什么每次都是ae8f？我TM也不知道！！AdvertiseData介绍完毕，下面再稍微介绍一下 AdvertiseSettingsAdvertiseSettings.Builder mSettingsbuilder = new AdvertiseSettings.Builder();mSettingsbuilder.setAdvertiseMode(AdvertiseSettings.ADVERTISE_MODE_LOW_LATENCY);mSettingsbuilder.setConnectable(connectable);mSettingsbuilder.setTxPowerLevel(AdvertiseSettings.ADVERTISE_TX_POWER_HIGH);mSettingsbuilder.setTimeout(0);AdvertiseSettings mAdvertiseSettings = mSettingsbuilder.build();setAdvertiseMode(int advertiseMode)设置广播的模式，低功耗，平衡和低延迟三种模式；对应  AdvertiseSettings.ADVERTISE_MODE_LOW_POWER  ,ADVERTISE_MODE_BALANCED ,ADVERTISE_MODE_LOW_LATENCY从左右到右，广播的间隔会越来越短 setConnectable(boolean connectable)设置是否可以连接。广播分为可连接广播和不可连接广播，一般不可连接广播应用在iBeacon设备上，这样APP无法连接上iBeacon设备setTimeout(int timeoutMillis)设置广播的最长时间，最大值为常量AdvertiseSettings.LIMITED_ADVERTISING_MAX_MILLIS = 180 * 1000;  180秒设为0时，代表无时间限制会一直广播setTxPowerLevel(int txPowerLevel)设置广播的信号强度常量有AdvertiseSettings.ADVERTISE_TX_POWER_ULTRA_LOW,ADVERTISE_TX_POWER_LOW,ADVERTISE_TX_POWER_MEDIUM,ADVERTISE_TX_POWER_HIGH 从左到右分别表示强度越来越强. 举例：当设置为ADVERTISE_TX_POWER_ULTRA_LOW时，手机1和手机2放在一起，手机2扫描到的rssi信号强度为-56左右，当设置为ADVERTISE_TX_POWER_HIGH  时， 扫描到的信号强度为-33左右，信号强度越大，表示手机和设备靠的越近好了，关于BluetoothLeAdvertiser 的用法介绍完毕！！！！可能有人会说，bluetoothAdapter.startLeScan(leScanCallback); 这个方法过时了怎么办，那可以看一下我的另一篇文章《android BLE 扫描BLE设备 BluetoothLeScanner》源码附件：模拟BLE广播源码：http://pan.baidu.com/s/1bptOQyb

手机2扫描打印的源码就不放出了，很简单。android BLE Peripheral 手机模拟设备发出BLE广播 BluetoothLeAdvertiser