Android对外模模式(peripheral)的支持：
从Android 5.0＋开始才支持。 api level >= 21
所以5.0 之前设备，是不能向外发送广播的。
Android中心设备(central)的支持：
从Android 4.3+ 。 api level >= 18
1、初始化蓝牙
2、检查ble是否可用
3、开启广播
4、扫描响应数据
5、创建iBeacon 广播数据
6、广播设置
7、开启广播后的回调
（1）初始化蓝牙：
添加权限：
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<!-- 6.0之后蓝牙还需要地理位置权限 -->
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" /> <!-- 自行判断 -->
<uses-feature
android:name="android.hardware.bluetooth_le"
android:required="false" />
初始化：
//初始化BluetoothManager和BluetoothAdapter
if (mBluetoothManager == null) {
mBluetoothManager = (BluetoothManager) mContext.getSystemService(BLUETOOTH_SERVICE);
} if (mBluetoothManager != null && mBluetoothAdapter == null) {
mBluetoothAdapter = mBluetoothManager.getAdapter();
}
（2）检查是否可使用ble：
if (!activity.getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
Toast.makeText(activity, "不支持ble", Toast.LENGTH_LONG).show(); return;
} final BluetoothManager mBluetoothManager = (BluetoothManager) activity.getSystemService(BLUETOOTH_SERVICE);
mBluetoothAdapter = mBluetoothManager.getAdapter(); if (mBluetoothAdapter == null) {
Toast.makeText(activity, "不支持ble", Toast.LENGTH_LONG).show(); return;
}
// 获取蓝牙ble广播
16 mBluetoothAdvertiser = mBluetoothAdapter.getBluetoothLeAdvertiser();
if (mBluetoothAdvertiser == null) {
Toast.makeText(activity, "the device not support peripheral", Toast.LENGTH_SHORT).show();
Log.e(TAG, "the device not support peripheral"); return;
}
（3）开启广播：
public void startAdvertising(MockServerCallBack callBack) {
//获取BluetoothLeAdvertiser，BLE发送BLE广播用的一个API
if (mBluetoothAdvertiser == null) {
mBluetoothAdvertiser = mBluetoothAdapter.getBluetoothLeAdvertiser();
}
if (mBluetoothAdvertiser != null) {try {
//创建BLE beacon Advertising并且广播
mBluetoothAdvertiser.startAdvertising(createAdvSettings(true, 0)
, createIBeaconAdvertiseData(BluetoothUUID.bleServerUUID,
mMajor, mMinor, mTxPower)
, createScanAdvertiseData(mMajor, mMinor, mTxPower, mAdvCallback);
} catch (Exception e) {
Log.v(TAG, "Fail to setup BleService");
}
}
}
一个ble广播包：广播数据其实包含两部分：Advertising Data（广播数据） 和 Scan Response Data（扫描响应数据）。
通常情况下，广播的一方，按照一定的间隔，往空中广播 Advertising Data。
当某个监听设备监听到这个广播数据时候，会通过发送 Scan Response Request，请求广播方发送扫描响应数据数据。
这两部分数据的长度都是固定的 31 字节。
在 Android 中，系统会把这两个数据拼接在一起，返回一个 62 字节的数组。
（4）扫描响应数据：
可以自定义数据，比如增加湿度，温度等。
//设置scan广播数据
public static AdvertiseData createScanAdvertiseData(short major, short minor, byte txPower) {
AdvertiseData.Builder builder = new AdvertiseData.Builder();
builder.setIncludeDeviceName(true); byte[] serverData = new byte[5];
ByteBuffer bb = ByteBuffer.wrap(serverData);
bb.order(ByteOrder.BIG_ENDIAN);
bb.putShort(major);
bb.putShort(minor);
bb.put(txPower);
builder.addServiceData(ParcelUuid.fromString(BluetoothUUID.bleServerUUID.toString())
, serverData); AdvertiseData adv = builder.build();
return adv;
}
5、创建ibeacon 广播数据。
iBeacon 的广播结构：iBeacon 只是协议.
- the 2 byte beacon identifier (0xBEAC)
- the 16 bytes UUID
- the 2 byte major
- the 2 byte minor
- the 1 byte tx power
Byte 0-2: Standard BLE Flags
Byte 0: Length : 0x02
Byte 1: Type: 0x01 (Flags)
Byte 2: Value: 0x06 (Typical Flags)
Byte 3-29: Apple Defined iBeacon Data
Byte 3: Length: 0x1a
Byte 4: Type: 0xff (Custom Manufacturer Packet)
Byte 5-6: Manufacturer ID : 0x4c00 (Apple)
Byte 7: SubType: 0x2 (iBeacon)
Byte 8: SubType Length: 0x15
Byte 9-24: Proximity UUID
Byte 25-26: Major
Byte 27-28: Minor
Byte 29: Signal Power
ManufactureData : 设备厂商的自定义数据
使用addManufactureData(int manufacturerId, byte[] manufacturerSpecificData);
第一个参数0x004c，是厂商id，id长度为2个字节，不足2个字节系统会补0.
（比如id传入0xac, 不足两个字节，输入广播时：ac, 00)
/**
* create AdvertiseDate for iBeacon
*/
public static AdvertiseData createIBeaconAdvertiseData(UUID proximityUuid, short major, short minor, byte txPower) { String[] uuidstr = proximityUuid.toString().replaceAll("-", "").toLowerCase().split("");
byte[] uuidBytes = new byte[16];
for (int i = 1, x = 0; i < uuidstr.length; x++) {
uuidBytes[x] = (byte) ((Integer.parseInt(uuidstr[i++], 16) << 4) | Integer.parseInt(uuidstr[i++], 16));
}
byte[] majorBytes = {(byte) (major >> 8), (byte) (major & 0xff)};
byte[] minorBytes = {(byte) (minor >> 8), (byte) (minor & 0xff)};
byte[] mPowerBytes = {txPower};
byte[] manufacturerData = new byte[0x17];
byte[] flagibeacon = {0x02, 0x15}; System.arraycopy(flagibeacon, 0x0, manufacturerData, 0x0, 0x2);
System.arraycopy(uuidBytes, 0x0, manufacturerData, 0x2, 0x10);
System.arraycopy(majorBytes, 0x0, manufacturerData, 0x12, 0x2);
System.arraycopy(minorBytes, 0x0, manufacturerData, 0x14, 0x2);
System.arraycopy(mPowerBytes, 0x0, manufacturerData, 0x16, 0x1); AdvertiseData.Builder builder = new AdvertiseData.Builder();
builder.addManufacturerData(0x004c, manufacturerData); AdvertiseData adv = builder.build();
return adv;
}
6、创建广播设置：模式，是否可连接，功率
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
＊ AdvertiseSettings.ADVERTISE_TX_POWER_HIGH -56 dBm @ 1 meter with Nexus 5
＊ AdvertiseSettings.ADVERTISE_TX_POWER_LOW -75 dBm @ 1 meter with Nexus 5
＊ AdvertiseSettings.ADVERTISE_TX_POWER_MEDIUM -66 dBm @ 1 meter with Nexus 5
＊AdvertiseSettings.ADVERTISE_TX_POWER_ULTRA_LOW not detected with Nexus 5
public AdvertiseSettings createAdvSettings(boolean connectable, int timeoutMillis) {
AdvertiseSettings.Builder builder = new AdvertiseSettings.Builder();
//设置广播的模式, 功耗相关
builder.setAdvertiseMode(AdvertiseSettings.ADVERTISE_MODE_BALANCED);
builder.setConnectable(connectable);
builder.setTimeout(timeoutMillis);
builder.setTxPowerLevel(AdvertiseSettings.ADVERTISE_TX_POWER_HIGH);
AdvertiseSettings mAdvertiseSettings = builder.build();
if (mAdvertiseSettings == null) {
Log.e(TAG, "mAdvertiseSettings == null");
}
return mAdvertiseSettings;
}
7、开始广播后的回调。提示广播开启是否成功。
//发送广播的回调，onStartSuccess/onStartFailure很明显的两个Callback
private AdvertiseCallback mAdvCallback = new AdvertiseCallback() {
public void onStartSuccess(android.bluetooth.le.AdvertiseSettings settingsInEffect) {
super.onStartSuccess(settingsInEffect);
if (settingsInEffect != null) {
Log.d(TAG, "onStartSuccess TxPowerLv=" + settingsInEffect.getTxPowerLevel() + " mode=" + settingsInEffect.getMode() + " timeout=" + settingsInEffect.getTimeout());
} else {
Log.d(TAG, "onStartSuccess, settingInEffect is null");
}
} public void onStartFailure(int errorCode) {
super.onStartFailure(errorCode);
Log.d(TAG, "onStartFailure errorCode=" + errorCode); if (errorCode == ADVERTISE_FAILED_DATA_TOO_LARGE) {
Toast.makeText(mContext, "advertise_failed_data_too_large", Toast.LENGTH_LONG).show();
Log.e(TAG, "Failed to start advertising as the advertise data to be broadcasted is larger than 31 bytes.");
} else if (errorCode == ADVERTISE_FAILED_TOO_MANY_ADVERTISERS) {
Toast.makeText(mContext, "advertise_failed_too_many_advertises", Toast.LENGTH_LONG).show();
Log.e(TAG, "Failed to start advertising because no advertising instance is available."); } else if (errorCode == ADVERTISE_FAILED_ALREADY_STARTED) {
Toast.makeText(mContext, "advertise_failed_already_started", Toast.LENGTH_LONG).show();
Log.e(TAG, "Failed to start advertising as the advertising is already started"); } else if (errorCode == ADVERTISE_FAILED_INTERNAL_ERROR) {
Toast.makeText(mContext, "advertise_failed_internal_error", Toast.LENGTH_LONG).show();
Log.e(TAG, "Operation failed due to an internal error"); } else if (errorCode == ADVERTISE_FAILED_FEATURE_UNSUPPORTED) {
Toast.makeText(mContext, "advertise_failed_feature_unsupported", Toast.LENGTH_LONG).show();
Log.e(TAG, "This feature is not supported on this platform"); }
}
};
注意：对于ios 设备接受广播，外围设备还是要广播出来一个16位的serviceUUID，因为扫描的时候要用（如果不指定特定服务的UUID，没有办法进行后台持续扫描连接）.
