BLE研究

掃描

掃描設備需要通過BletoothManager獲取到BluetoothAdapter對象進行掃描，在BluetoothAdapter.LeScanCallback回調中返回結果：

final BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
mBluetoothAdapter = bluetoothManager.getAdapter();
mBluetoothAdapter.startLeScan(mLeScanCallback);

private BluetoothAdapter.LeScanCallback mLeScanCallback =
        new BluetoothAdapter.LeScanCallback() {
    @Override
    public void onLeScan(final BluetoothDevice device, int rssi,
            byte[] scanRecord) {
        //掃描結果
   }
};

mBluetoothAdapter.stopLeScan(mLeScanCallback);   //停止掃描

連接

調用掃描到的設備BluetoothDevice的connectGatt接口進行連接，通過回調BluetoothGattCallback返回連接結果：

mBluetoothGatt = device.connectGatt(this, false, mGattCallback);

連接後調用BluetoothGatt的discoverServices發現服務後進行傳輸數據。

傳輸數據

服務是設備的屬性，特徵是服務的屬性，描述是特徵的屬性，暫時這麼理解吧。發數據和收數據都是通過讀特徵值，寫特徵值進行的。服務，特徵，描述都有各自的UUID，可以通過UUID區分他們。

讀數據之前要設置特徵的notify屬性，也就是設置讀取的數據可以通過回調返回，不然收不到數據。設置特徵notify需要調用BluetoothGatt的setCharacteristicNotify(mCharacter ,true)和修改對應特徵的描述纔行。

所有這些操作都是在BluetoothGattCallback回調中收到結果。

mBluetoothGatt.discoverServices();                                   //對應onServicesDiscovered
mBluetoothGatt.setCharacteristicNotification(mCharacter, true);      //對應onCharacteristicChanged
mBluetoothGatt.readCharacteristic(mCharacter);                       //對應onCharacteristicRead
mBluetoothGatt.writeCharacteristic(mCharacter);                      //對應onCharacteristicWrite
mBluetoothGatt.readDescriptor(mDescriptor);                          //對應onDescriptorRead
mBluetoothGatt.writeDescriptor(mDescriptor);                         //對應onDescriptorWrite

private BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
        @Override
        public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
            Log.d(LOG_TAG, "onConnectionSateChange staus = " + status + ",newState = " + newState);
        }

        @Override
        public void onServicesDiscovered(BluetoothGatt gatt, int status) {
            Log.d(LOG_TAG, "onServicesDiscovered status = " + status);
        }

        @Override
        public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
            Log.d(LOG_TAG, "onCharacteristicChanged");
        }

        @Override
        public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
            Log.d(LOG_TAG, "onCharacteristicRead");
        }

        @Override
        public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
            Log.d(LOG_TAG, "onCharacteristicWrite");
        }

        @Override
        public void onDescriptorRead(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {
            Log.d(LOG_TAG, "onDescriptorRead");
        }

        @Override
        public void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {
            Log.d(LOG_TAG, "onDescriptorWrite");
        }
    };

獲取服務，特徵，描述

        BluetoothGattService mService;
        BluetoothGattCharacteristic mCharacter;
        BluetoothGattDescriptor mDescriptor;
        mBluetoothGatt.getServices();
        mService = mBluetoothGatt.getService(mServiceUUID);
        mService.getUuid();
        mService.getCharacteristics();
        mCharacter = mService.getCharacteristic(mCharacterUUID);
        mCharacter.getUuid();
        mCharacter.getDescriptors();
        mDescriptor = mCharacter.getDescriptor(mDescriptorUUID);
        mDescriptor.getUuid();