05-05 12：29：08.884 28549-28562/com.example.android.bluetoothlegatt I/BluetoothLeService： onCharacteristicChanged 05-05 12：29：08.884 28549-28562/com.example.android.bluetoothlegatt D/BluetoothLeService：收到的消息：[J[ 23.1381098429305-05 12：29：08.921 28549-28562/com.example.android.bluetoothlegatt I/BluetoothLeService：onCharacteristicChanged 05-05 12：29：08.922 28549-28562/com.example.android.bluetoothlegatt D/BluetoothLeService： 收到的消息：， 25， 2.9， 0]
我已经在我的安卓应用程序中与我的 Puck.js ble 设备配对，但我得到的数据以错误的格式显示(粗体值)。如何分别取每个值？提前感谢！
package com.example.android.bluetoothlegatt;
import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCallback;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattDescriptor;
import android.bluetooth.BluetoothGattService;
import android.bluetooth.BluetoothManager;
import android.bluetooth.BluetoothProfile;
import android.content.Context;
import android.content.Intent;
import android.os.Binder;
import android.os.IBinder;
import android.util.Log;
import java.io.UnsupportedEncodingException;
import java.util.List;
/**
* Service for managing connection and data communication with a GATT server hosted on a
* given Bluetooth LE device.
*/
public class BluetoothLeService extends Service {
private final static String TAG = BluetoothLeService.class.getSimpleName();
private BluetoothManager mBluetoothManager;
private BluetoothAdapter mBluetoothAdapter;
private String mBluetoothDeviceAddress;
private BluetoothGatt mBluetoothGatt;
private int mConnectionState = STATE_DISCONNECTED;
private static final int STATE_DISCONNECTED = 0;
private static final int STATE_CONNECTING = 1;
private static final int STATE_CONNECTED = 2;
public final static String ACTION_GATT_CONNECTED =
"com.example.bluetooth.le.ACTION_GATT_CONNECTED";
public final static String ACTION_GATT_DISCONNECTED =
"com.example.bluetooth.le.ACTION_GATT_DISCONNECTED";
public final static String ACTION_GATT_SERVICES_DISCOVERED =
"com.example.bluetooth.le.ACTION_GATT_SERVICES_DISCOVERED";
public final static String ACTION_DATA_AVAILABLE =
"com.example.bluetooth.le.ACTION_DATA_AVAILABLE";
public final static String EXTRA_DATA =
"com.example.bluetooth.le.EXTRA_DATA";
// Implements callback methods for GATT events that the app cares about. For example,
// connection change and services discovered.
private final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
String intentAction;
if (newState == BluetoothProfile.STATE_CONNECTED) {
intentAction = ACTION_GATT_CONNECTED;
mConnectionState = STATE_CONNECTED;
broadcastUpdate(intentAction);
Log.i(TAG, "Connected to GATT server.");
// Attempts to discover services after successful connection.
Log.i(TAG, "Attempting to start service discovery:" +
mBluetoothGatt.discoverServices());
} else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
intentAction = ACTION_GATT_DISCONNECTED;
mConnectionState = STATE_DISCONNECTED;
Log.i(TAG, "Disconnected from GATT server.");
broadcastUpdate(intentAction);
}
}
@Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED);
setPuckCharacteristicNotification();
} else {
Log.w(TAG, "onServicesDiscovered received: " + status);
}
}
@Override
public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
if (status == BluetoothGatt.GATT_SUCCESS) {
Log.i(TAG, "onCharacteristicRead");
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
}
}
@Override
public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
Log.i(TAG, "onCharacteristicChanged");
byte[] messageBytes = characteristic.getValue();
String messageString = null;
try {
messageString = new String(messageBytes, "UTF-8");
} catch (UnsupportedEncodingException e) {
Log.e(TAG, "Unable to convert message bytes to string");
}
Log.d(TAG, "Received message: " + messageString);
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
}
@Override
public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
Log.i(TAG, "onCharacteristicWrite");
}
@Override
public void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {
Log.i(TAG, "onDescriptorWrite");
BluetoothGattService service = gatt.getService(G.PUCK_SERVICE_UUID);
if (service != null) {
BluetoothGattCharacteristic characteristic =
service.getCharacteristic(G.PUCK_TX_UUID);
if (characteristic != null) {
Log.i(TAG, "Writing to characteristic " + characteristic.getUuid());
String msg = "E.getTemperature()n";
byte[] data = msg.getBytes();
characteristic.setValue(data);
if (gatt.writeCharacteristic(characteristic)) {
Log.i(TAG, "writeCharacteristic OK");
} else {
Log.i(TAG, "writeCharacteristic FAIL");
}
}
}
}
};
private void broadcastUpdate(final String action) {
final Intent intent = new Intent(action);
sendBroadcast(intent);
}
private void broadcastUpdate(final String action,
final BluetoothGattCharacteristic characteristic) {
final Intent intent = new Intent(action);
// This is special handling for the Heart Rate Measurement profile. Data parsing is
// carried out as per profile specifications:
// http://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.heart_rate_measurement.xml
if (G.PUCK_RX_UUID.equals(characteristic.getUuid())) {
int flag = characteristic.getProperties();
int format = -1;
/*if ((flag & 0x01) != 0) {
format = BluetoothGattCharacteristic.FORMAT_UINT16;
Log.i(TAG, "Heart rate format UINT16.");
} else {
format = BluetoothGattCharacteristic.FORMAT_UINT8;
Log.i(TAG, "Heart rate format UINT8.");
}*/
//final int heartRate = characteristic.getIntValue(format, 1);
//Log.i(TAG, String.format("Received heart rate: %d", heartRate));
//intent.putExtra(EXTRA_DATA, String.valueOf(heartRate));
} else {
// For all other profiles, writes the data formatted in HEX.
final byte[] data = characteristic.getValue();
if (data != null && data.length > 0) {
final StringBuilder stringBuilder = new StringBuilder(data.length);
for (byte byteChar : data)
stringBuilder.append(String.format("%02X ", byteChar));
intent.putExtra(EXTRA_DATA, new String(data) + "n" + stringBuilder.toString());
}
}
sendBroadcast(intent);
}
public class LocalBinder extends Binder {
BluetoothLeService getService() {
return BluetoothLeService.this;
}
}
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
@Override
public boolean onUnbind(Intent intent) {
// After using a given device, you should make sure that BluetoothGatt.close() is called
// such that resources are cleaned up properly. In this particular example, close() is
// invoked when the UI is disconnected from the Service.
close();
return super.onUnbind(intent);
}
private final IBinder mBinder = new LocalBinder();
/**
* Initializes a reference to the local Bluetooth adapter.
*
* @return Return true if the initialization is successful.
*/
public boolean initialize() {
// For API level 18 and above, get a reference to BluetoothAdapter through
// BluetoothManager.
if (mBluetoothManager == null) {
mBluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
if (mBluetoothManager == null) {
Log.e(TAG, "Unable to initialize BluetoothManager.");
return false;
}
}
mBluetoothAdapter = mBluetoothManager.getAdapter();
if (mBluetoothAdapter == null) {
Log.e(TAG, "Unable to obtain a BluetoothAdapter.");
return false;
}
return true;
}
/**
* Connects to the GATT server hosted on the Bluetooth LE device.
*
* @param address The device address of the destination device.
* @return Return true if the connection is initiated successfully. The connection result
* is reported asynchronously through the
* {@code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)}
* callback.
*/
public boolean connect(final String address) {
if (mBluetoothAdapter == null || address == null) {
Log.w(TAG, "BluetoothAdapter not initialized or unspecified address.");
return false;
}
// Previously connected device. Try to reconnect.
if (mBluetoothDeviceAddress != null && address.equals(mBluetoothDeviceAddress)
&& mBluetoothGatt != null) {
Log.i(TAG, "Trying to use an existing mBluetoothGatt for connection.");
if (mBluetoothGatt.connect()) {
mConnectionState = STATE_CONNECTING;
return true;
} else {
return false;
}
}
final BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
if (device == null) {
Log.w(TAG, "Device not found. Unable to connect.");
return false;
}
// We want to directly connect to the device, so we are setting the autoConnect
// parameter to false.
mBluetoothGatt = device.connectGatt(this, false, mGattCallback);
Log.i(TAG, "Trying to create a new connection.");
mBluetoothDeviceAddress = address;
mConnectionState = STATE_CONNECTING;
return true;
}
/**
* Disconnects an existing connection or cancel a pending connection. The disconnection result
* is reported asynchronously through the
* {@code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)}
* callback.
*/
public void disconnect() {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
mBluetoothGatt.disconnect();
}
/**
* After using a given BLE device, the app must call this method to ensure resources are
* released properly.
*/
public void close() {
if (mBluetoothGatt == null) {
return;
}
mBluetoothGatt.close();
mBluetoothGatt = null;
}
/**
* Request a read on a given {@code BluetoothGattCharacteristic}. The read result is reported
* asynchronously through the {@code BluetoothGattCallback#onCharacteristicRead(android.bluetooth.BluetoothGatt, android.bluetooth.BluetoothGattCharacteristic, int)}
* callback.
*
* @param characteristic The characteristic to read from.
*/
public void readCharacteristic(BluetoothGattCharacteristic characteristic) {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
mBluetoothGatt.readCharacteristic(characteristic);
}
/**
* Enables notification on a given characteristic.
**/
public void setPuckCharacteristicNotification() {
if (mBluetoothAdapter == null || mBluetoothGatt == null) {
Log.w(TAG, "BluetoothAdapter not initialized");
return;
}
//Start getting data
BluetoothGattService gattService = mBluetoothGatt.getService(G.PUCK_SERVICE_UUID);
if (gattService != null) {
BluetoothGattCharacteristic gattCharacteristic = gattService.getCharacteristic(G.PUCK_RX_UUID);
if (gattCharacteristic != null) {
Log.i(TAG, "Setting Characteristic " + gattCharacteristic.getUuid());
mBluetoothGatt.setCharacteristicNotification(gattCharacteristic, true);
BluetoothGattDescriptor clientDescriptor = gattCharacteristic.getDescriptor(G.CLIENT_CHARACTERISTIC_CONFIG);
clientDescriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
mBluetoothGatt.writeDescriptor(clientDescriptor);
}
}
}
/**
* Retrieves a list of supported GATT services on the connected device. This should be
* invoked only after {@code BluetoothGatt#discoverServices()} completes successfully.
*
* @return A {@code List} of supported services.
*/
public List<BluetoothGattService> getSupportedGattServices() {
if (mBluetoothGatt == null) return null;
return mBluetoothGatt.getServices();
}
}
要查找接收到的结果，请以原始字节数组的形式获取结果。
几乎所有BLE设备都使用小端序， 所以如果一对字节一起组成一个数字，你必须交换字节.
在十六进制(小端序)中，E2 07 变为 07 E2 =2018 (7 x 256 + 226)。
在大端序中，它是 57863(226 x 256 + 7)。
最多 255 的小数字将是单个字节，例如日期和时间、ASCII 或 Utf8 编码的一部分。 像年份或哈特率这样的大数字将是 2 个或更多字节。
您必须找出顺序以及哪些字节是单个或成对的，但这是一个简单的难题。
我的代码尝试，不要指望它能工作！
@Override
public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
Log.i(TAG, "onCharacteristicChanged");
byte[] messageBytes = characteristic.getValue();
for(byte b : messageBytes){
Log.d(TAG, b);
}
broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
}