Android BLE开发之Android手机与BLE终端通信

本文来自http://blog.csdn.net/hellogv/ ，引用必须注明出处！

最近穿戴设备发展得很火，把相关技术也带旺了，其中一项是BLE（Bluetooth Low Energy）。BLE是蓝牙4.0的核心Profile，主打功能是快速搜索，快速连接，超低功耗保持连接和传输数据，弱点是数据传输速率低，由于BLE的低功耗特点，因此普遍用于穿戴设备。Android 4.3才开始支持BLE API，所以请各位客官把本文代码运行在蓝牙4.0和Android 4.3及其以上的系统，另外本文所用的BLE终端是一个蓝牙4.0的串口蓝牙模块。

PS：我的i9100刷了4.4系统后，竟然也能跟BLE蓝牙模块通信。

BLE分为三部分Service、Characteristic、Descriptor，这三部分都由UUID作为唯一标示符。一个蓝牙4.0的终端可以包含多个Service，一个Service可以包含多个Characteristic，一个Characteristic包含一个Value和多个Descriptor，一个Descriptor包含一个Value。一般来说，Characteristic是手机与BLE终端交换数据的关键，Characteristic有较多的跟权限相关的字段，例如PERMISSION和PROPERTY，而其中最常用的是PROPERTY，本文所用的BLE蓝牙模块竟然没有标准的Characteristic的PERMISSION。Characteristic的PROPERTY可以通过位运算符组合来设置读写属性，例如READ|WRITE、READ|WRITE_NO_RESPONSE|NOTIFY，因此读取PROPERTY后要分解成所用的组合（本文代码已含此分解方法）。

本文代码改自Android 4.3 Sample的BluetoothLeGatt，把冗余代码去掉，获取的BLE设备信息都通过Log，还有一些必要的读写蓝牙方法，应该算是简化到大家一看就可以懂了。本文代码可以到http://download.csdn.net/detail/hellogv/7228819下载。接下来贴出本文运行的结果，首先是连接BLE设备后，枚举出设备所有Service、Characteristic、Descriptor，并且手机会往Characteristic uuid=0000ffe1-0000-1000-8000-00805f9b34fb写入“send data->”字符串，BLE终端收到数据通过串口传到PC串口助手（见PC串口助手的截图）：

04-21 18:28:25.465: E/DeviceScanActivity(12254): -->service type:PRIMARY
04-21 18:28:25.465: E/DeviceScanActivity(12254): -->includedServices size:0
04-21 18:28:25.465: E/DeviceScanActivity(12254): -->service uuid:00001800-0000-1000-8000-00805f9b34fb
04-21 18:28:25.465: E/DeviceScanActivity(12254): ---->char uuid:00002a00-0000-1000-8000-00805f9b34fb
04-21 18:28:25.465: E/DeviceScanActivity(12254): ---->char permission:UNKNOW
04-21 18:28:25.465: E/DeviceScanActivity(12254): ---->char property:READ
04-21 18:28:25.465: E/DeviceScanActivity(12254): ---->char uuid:00002a01-0000-1000-8000-00805f9b34fb
04-21 18:28:25.470: E/DeviceScanActivity(12254): ---->char permission:UNKNOW
04-21 18:28:25.470: E/DeviceScanActivity(12254): ---->char property:READ
04-21 18:28:25.470: E/DeviceScanActivity(12254): ---->char uuid:00002a02-0000-1000-8000-00805f9b34fb
04-21 18:28:25.470: E/DeviceScanActivity(12254): ---->char permission:UNKNOW
04-21 18:28:25.470: E/DeviceScanActivity(12254): ---->char property:READ|WRITE|
04-21 18:28:25.470: E/DeviceScanActivity(12254): ---->char uuid:00002a03-0000-1000-8000-00805f9b34fb
04-21 18:28:25.470: E/DeviceScanActivity(12254): ---->char permission:UNKNOW
04-21 18:28:25.475: E/DeviceScanActivity(12254): ---->char property:READ|WRITE|
04-21 18:28:25.475: E/DeviceScanActivity(12254): ---->char uuid:00002a04-0000-1000-8000-00805f9b34fb
04-21 18:28:25.475: E/DeviceScanActivity(12254): ---->char permission:UNKNOW
04-21 18:28:25.475: E/DeviceScanActivity(12254): ---->char property:READ
04-21 18:28:25.475: E/DeviceScanActivity(12254): -->service type:PRIMARY
04-21 18:28:25.475: E/DeviceScanActivity(12254): -->includedServices size:0
04-21 18:28:25.475: E/DeviceScanActivity(12254): -->service uuid:00001801-0000-1000-8000-00805f9b34fb
04-21 18:28:25.480: E/DeviceScanActivity(12254): ---->char uuid:00002a05-0000-1000-8000-00805f9b34fb
04-21 18:28:25.480: E/DeviceScanActivity(12254): ---->char permission:UNKNOW
04-21 18:28:25.480: E/DeviceScanActivity(12254): ---->char property:INDICATE
04-21 18:28:25.480: E/DeviceScanActivity(12254): -------->desc uuid:00002902-0000-1000-8000-00805f9b34fb
04-21 18:28:25.480: E/DeviceScanActivity(12254): -------->desc permission:UNKNOW
04-21 18:28:25.480: E/DeviceScanActivity(12254): -->service type:PRIMARY
04-21 18:28:25.480: E/DeviceScanActivity(12254): -->includedServices size:0
04-21 18:28:25.480: E/DeviceScanActivity(12254): -->service uuid:0000ffe0-0000-1000-8000-00805f9b34fb
04-21 18:28:25.480: E/DeviceScanActivity(12254): ---->char uuid:0000ffe1-0000-1000-8000-00805f9b34fb
04-21 18:28:25.480: E/DeviceScanActivity(12254): ---->char permission:UNKNOW
04-21 18:28:25.480: E/DeviceScanActivity(12254): ---->char property:READ|WRITE_NO_RESPONSE|NOTIFY|
04-21 18:28:25.490: E/DeviceScanActivity(12254): -------->desc uuid:00002902-0000-1000-8000-00805f9b34fb
04-21 18:28:25.490: E/DeviceScanActivity(12254): -------->desc permission:UNKNOW
04-21 18:28:25.490: E/DeviceScanActivity(12254): -------->desc uuid:00002901-0000-1000-8000-00805f9b34fb
04-21 18:28:25.490: E/DeviceScanActivity(12254): -------->desc permission:UNKNOW
04-21 18:28:26.025: E/DeviceScanActivity(12254): onCharRead BLE DEVICE read 0000ffe1-0000-1000-8000-00805f9b34fb -> 00

这里红字是由BluetoothGattCallback的onCharacteristicRead()回调而打出Log

以下Log是PC上的串口工具通过BLE模块发送过来，由BluetoothGattCallback的 onCharacteristicChanged（）打出Log
04-21 18:30:18.260: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:18.745: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:19.085: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:19.350: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:19.605: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:19.835: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:20.055: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:20.320: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:20.510: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:20.735: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone
04-21 18:30:21.000: E/DeviceScanActivity(12254): onCharWrite BLE DEVICE write 0000ffe1-0000-1000-8000-00805f9b34fb -> send data to phone

接下来贴出本文核心代码：

 public class DeviceScanActivity extends ListActivity {
     private final static String TAG = DeviceScanActivity.class.getSimpleName();
     private final static String UUID_KEY_DATA = "0000ffe1-0000-1000-8000-00805f9b34fb";

     private LeDeviceListAdapter mLeDeviceListAdapter;
     /**搜索BLE终端*/
     private BluetoothAdapter mBluetoothAdapter;
     /**读写BLE终端*/
     private BluetoothLeClass mBLE;
     private boolean mScanning;
     private Handler mHandler;

     // Stops scanning after 10 seconds.
     private static final long SCAN_PERIOD = 10000;

     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         getActionBar().setTitle(R.string.title_devices);
         mHandler = new Handler();

         // Use this check to determine whether BLE is supported on the device.  Then you can
         // selectively disable BLE-related features.
         if (!getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
             Toast.makeText(this, R.string.ble_not_supported, Toast.LENGTH_SHORT).show();
             finish();
         }

         // Initializes a Bluetooth adapter.  For API level 18 and above, get a reference to
         // BluetoothAdapter through BluetoothManager.
         final BluetoothManager bluetoothManager =
                 (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
         mBluetoothAdapter = bluetoothManager.getAdapter();

         // Checks if Bluetooth is supported on the device.
         if (mBluetoothAdapter == null) {
             Toast.makeText(this, R.string.error_bluetooth_not_supported, Toast.LENGTH_SHORT).show();
             finish();
             return;
         }
         //开启蓝牙
         mBluetoothAdapter.enable();

         mBLE = new BluetoothLeClass(this);
         if (!mBLE.initialize()) {
             Log.e(TAG, "Unable to initialize Bluetooth");
             finish();
         }
         //发现BLE终端的Service时回调
         mBLE.setOnServiceDiscoverListener(mOnServiceDiscover);
         //收到BLE终端数据交互的事件
         mBLE.setOnDataAvailableListener(mOnDataAvailable);
     }


     @Override
     protected void onResume() {
         super.onResume();

         // Initializes list view adapter.
         mLeDeviceListAdapter = new LeDeviceListAdapter(this);
         setListAdapter(mLeDeviceListAdapter);
         scanLeDevice(true);
     }

     @Override
     protected void onPause() {
         super.onPause();
         scanLeDevice(false);
         mLeDeviceListAdapter.clear();
         mBLE.disconnect();
     }

     @Override
     protected void onStop() {
         super.onStop();
         mBLE.close();
     }

     @Override
     protected void onListItemClick(ListView l, View v, int position, long id) {
         final BluetoothDevice device = mLeDeviceListAdapter.getDevice(position);
         if (device == null) return;
         if (mScanning) {
             mBluetoothAdapter.stopLeScan(mLeScanCallback);
             mScanning = false;
         }

         mBLE.connect(device.getAddress());
     }

     private void scanLeDevice(final boolean enable) {
         if (enable) {
             // Stops scanning after a pre-defined scan period.
             mHandler.postDelayed(new Runnable() {
                 @Override
                 public void run() {
                     mScanning = false;
                     mBluetoothAdapter.stopLeScan(mLeScanCallback);
                     invalidateOptionsMenu();
                 }
             }, SCAN_PERIOD);

             mScanning = true;
             mBluetoothAdapter.startLeScan(mLeScanCallback);
         } else {
             mScanning = false;
             mBluetoothAdapter.stopLeScan(mLeScanCallback);
         }
         invalidateOptionsMenu();
     }

     /**
      * 搜索到BLE终端服务的事件
      */
     private BluetoothLeClass.OnServiceDiscoverListener mOnServiceDiscover = new OnServiceDiscoverListener(){

         @Override
         public void onServiceDiscover(BluetoothGatt gatt) {
             displayGattServices(mBLE.getSupportedGattServices());
         }

     };

     /**
      * 收到BLE终端数据交互的事件
      */
     private BluetoothLeClass.OnDataAvailableListener mOnDataAvailable = new OnDataAvailableListener(){

         /**
          * BLE终端数据被读的事件
          */
         @Override
         public void onCharacteristicRead(BluetoothGatt gatt,
                 BluetoothGattCharacteristic characteristic, int status) {
             if (status == BluetoothGatt.GATT_SUCCESS)
                 Log.e(TAG,"onCharRead "+gatt.getDevice().getName()
                         +" read "
                         +characteristic.getUuid().toString()
                         +" -> "
                         +Utils.bytesToHexString(characteristic.getValue()));
         }

         /**
          * 收到BLE终端写入数据回调
          */
         @Override
         public void onCharacteristicWrite(BluetoothGatt gatt,
                 BluetoothGattCharacteristic characteristic) {
             Log.e(TAG,"onCharWrite "+gatt.getDevice().getName()
                     +" write "
                     +characteristic.getUuid().toString()
                     +" -> "
                     +new String(characteristic.getValue()));
         }
     };

     // Device scan callback.
     private BluetoothAdapter.LeScanCallback mLeScanCallback =
             new BluetoothAdapter.LeScanCallback() {

         @Override
         public void onLeScan(final BluetoothDevice device, int rssi, byte[] scanRecord) {
             runOnUiThread(new Runnable() {
                 @Override
                 public void run() {
                     mLeDeviceListAdapter.addDevice(device);
                     mLeDeviceListAdapter.notifyDataSetChanged();
                 }
             });
         }
     };

     private void displayGattServices(List gattServices) {
         if (gattServices == null) return;

         for (BluetoothGattService gattService : gattServices) {
             //-----Service的字段信息-----//
             int type = gattService.getType();
             Log.e(TAG,"-->service type:"+Utils.getServiceType(type));
             Log.e(TAG,"-->includedServices size:"+gattService.getIncludedServices().size());
             Log.e(TAG,"-->service uuid:"+gattService.getUuid());

             //-----Characteristics的字段信息-----//
             List gattCharacteristics =gattService.getCharacteristics();
             for (final BluetoothGattCharacteristic  gattCharacteristic: gattCharacteristics) {
                 Log.e(TAG,"---->char uuid:"+gattCharacteristic.getUuid());

                 int permission = gattCharacteristic.getPermissions();
                 Log.e(TAG,"---->char permission:"+Utils.getCharPermission(permission));

                 int property = gattCharacteristic.getProperties();
                 Log.e(TAG,"---->char property:"+Utils.getCharPropertie(property));

                 byte[] data = gattCharacteristic.getValue();
                 if (data != null && data.length > 0) {
                     Log.e(TAG,"---->char value:"+new String(data));
                 }

                 //UUID_KEY_DATA是可以跟蓝牙模块串口通信的Characteristic
                 if(gattCharacteristic.getUuid().toString().equals(UUID_KEY_DATA)){
                     //测试读取当前Characteristic数据，会触发mOnDataAvailable.onCharacteristicRead()
                     mHandler.postDelayed(new Runnable() {
                         @Override
                         public void run() {
                             mBLE.readCharacteristic(gattCharacteristic);
                         }
                     }, 500);

                     //接受Characteristic被写的通知,收到蓝牙模块的数据后会触发mOnDataAvailable.onCharacteristicWrite()
                     mBLE.setCharacteristicNotification(gattCharacteristic, true);
                     //设置数据内容
                     gattCharacteristic.setValue("send data->");
                     //往蓝牙模块写入数据
                     mBLE.writeCharacteristic(gattCharacteristic);
                 }

                 //-----Descriptors的字段信息-----//
                 List gattDescriptors = gattCharacteristic.getDescriptors();
                 for (BluetoothGattDescriptor gattDescriptor : gattDescriptors) {
                     Log.e(TAG, "-------->desc uuid:" + gattDescriptor.getUuid());
                     int descPermission = gattDescriptor.getPermissions();
                     Log.e(TAG,"-------->desc permission:"+ Utils.getDescPermission(descPermission));

                     byte[] desData = gattDescriptor.getValue();
                     if (desData != null && desData.length > 0) {
                         Log.e(TAG, "-------->desc value:"+ new String(desData));
                     }
                  }
             }
         }//

     }
 }

【原文：http://blog.csdn.net/hellogv/article/details/24267685】