Android蓝牙LE连接至心率监测器

Question

I am absolutely new to android programming and Bluetooth LE. So pls be patient ;) I have a few example programs, but they are pretty hard to understand. I am currently working on an program, which should display the heart rate, received form a chest strap (Zephyr HXM2) by Bluetooth LE. I managed to get a connection and to read characteristics like the serial number string. But where I do have problems is in getting the heart rate measurement (UUID = 0x2A37) .

So what my program actually does is:

enabling the notification of the descriptor (UUID =00002902-0000-1000-8000-00805f9b34fb)

descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
mBluetoothGatt.writeDescriptor(descriptor);

then I wait for the onCharacteristicChanged Method and do the getvalue function.

BluetoothGattCharacteristic.getValue()

First thing I don't know if this is the right way, secondly I get data, but it varies from 2,4 and 6 bytes. Don't know what to do with them.

Answer 1

Last time I worked with the Zephyr heart rate monitor I simply set a few constants:

private static final int HEART_RATE = 0x100;
private static final int RESPIRATION_RATE = 0x101;
private static final int SKIN_TEMPERATURE = 0x102;
private static final int POSTURE = 0x103;
private static final int PEAK_ACCLERATION = 0x104;

then created a message handler with a switch statement:

@Override
public void handleMessage(Message msg) {
    switch (msg.what) {
        case HEART_RATE:
            // do stuff
            break;
        case RESPIRATION_RATE:
            // do stuff
            break;
    }
}

then get data out with calls such as msg.getData().getString("RespirationRate"); and msg.getData().getString("SkinTemperature");