java - 使用小米手环和 BLE 测量心率

Question

我正在尝试实现简单的 sdk 以与健身追踪器小米手环配合使用。目前我可以跟踪步数、启动振动、处理传感器触摸，但我在心率测量方面遇到问题。我的 sdk 基于 https://github.com/pangliang/miband-sdk-android .为了测量心率，我需要将描述符写入适当的特性，以便在该特性的值更改时启用处理回调，然后将适当的数据写入心率控制点特性以直接启动心率测量过程。问题是在启动此过程的数据成功写入特征后心率测量过程未启动(当Mi Band开始测量心率时底部传感器闪烁绿色)。这可能是由于健身手环的新固件(固件版本:4.15.12.10；HeartRate 版本:1.3.74.64)引起的，或者我的代码存在一些缺陷:

/-------- MiBandProfile --------/
public static final UUID UUID_SERVICE_HEARTRATE = UUID.fromString("0000180d-0000-1000-8000-00805f9b34fb");
public static final UUID UUID_NOTIFICATION_HEARTRATE = UUID.fromString("00002a37-0000-1000-8000-00805f9b34fb");
public static final UUID UUID_CHAR_HEARTRATE = UUID.fromString("00002a39-0000-1000-8000-00805f9b34fb");
public static final UUID UUID_DESCRIPTOR_UPDATE_NOTIFICATION = UUID.fromString("00002902-0000-1000-8000-00805f9b34fb");

/-------- MiBandProtocol --------/
public static final byte[] START_HEART_RATE_SCAN = {21, 1, 1};

/-------- BleProvider --------/
public class BleProvider extends BluetoothGattCallback {

public interface NotifyListener {
     void onNotify(byte[] data);
}

private HashMap<UUID, NotifyListener> mNotifyListeners = new HashMap<UUID, NotifyListener>();
.
.
.
public void setNotifyListener(UUID serviceUUID, UUID charaUUID, NotifyListener listener) {
        //enable chara notofication
        if (this.mGatt == null || !this.mIsServicesDiscovered) {
            if (DBG) Log.d(Debug.TAG, "Device is not connected or services are not discovered");
            return;
        }

        BluetoothGattCharacteristic chara = this.mGatt.getService(serviceUUID).getCharacteristic(charaUUID);

        if (DBG) Log.d(Debug.TAG, "setCharacteristicNotification: " + this.mGatt.setCharacteristicNotification(chara, true));
        BluetoothGattDescriptor descriptor = chara.getDescriptor(MiBandProfile.UUID_DESCRIPTOR_UPDATE_NOTIFICATION);
        if (DBG) Log.d(Debug.TAG, "setValue: " + descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE));
        if (DBG) Log.d(Debug.TAG, "writeDescriptor: " + this.mGatt.writeDescriptor(descriptor));
        this.mNotifyListeners.put(charaUUID, listener);
}

@Override
public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
        //this method must be called when the characteristic value was changed but nothing happened :(
        super.onCharacteristicChanged(gatt, characteristic);

        if (this.mNotifyListeners.containsKey(characteristic.getUuid())) {
            this.mNotifyListeners.get(characteristic.getUuid()).onNotify(characteristic.getValue());
        }
}
} //end BleProvider

.
.
.

setNotifyListener(MiBandProfile.UUID_SERVICE_HEARTRATE, MiBandProfile.UUID_NOTIFICATION_HEARTRATE, new BleProvider.NotifyListener(){...});
//waiting few seconds
writeCharacteristic(MiBandProfile.UUID_SERVICE_HEARTRATE, MiBandProfile.UUID_CHAR_HEARTRATE, MiBandProtocol.START_HEART_RATE_SCAN);

也许该协议(protocol)已被弃用，有人可以与我分享一个新协议(protocol)。我会很高兴)谢谢。

Answer 1

我解决了这个问题!在调用 setNotifyListener 跟踪脉搏值的变化之前，您必须将用户信息(年龄、体重)写入适当的特征，因为没有这个小米手环不会开始测量。