BluetoothGattCallback只调用onConnectionStateChange

Question

我的device.connectGatt()只触发onConnectionStateChage。状态为0，并建立了连接。我在4.4和5.1系统上测试了它--结果是一样的。这是我的密码：

private final BluetoothGattCallback myCallBack = new BluetoothGattCallback() {
    @Override
    public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
        super.onConnectionStateChange(gatt, status, newState);

        //BluetoothGattCharacteristic tempChar = null;
        //tempChar.setValue("test");

        if(status == 0) {
            gatt.connect();
            //gatt.disconnect();


        }
    }

    @Override
    public void onServicesDiscovered(BluetoothGatt gatt, int status) {
        super.onServicesDiscovered(gatt, status);
    }

    @Override
    public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
        super.onCharacteristicRead(gatt, characteristic, status);
    }

    @Override
    public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic, int status) {
        super.onCharacteristicWrite(gatt, characteristic, status);
        // Try to send some data to the device
        characteristic.setValue("test");
        gatt.writeCharacteristic(characteristic);
    }

    @Override
    public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
        super.onCharacteristicChanged(gatt, characteristic);


    }

    @Override
    public void onDescriptorRead(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {
        super.onDescriptorRead(gatt, descriptor, status);
    }

    @Override
    public void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor descriptor, int status) {
        super.onDescriptorWrite(gatt, descriptor, status);

    }

    @Override
    public void onReliableWriteCompleted(BluetoothGatt gatt, int status) {
        super.onReliableWriteCompleted(gatt, status);
    }

    @Override
    public void onReadRemoteRssi(BluetoothGatt gatt, int rssi, int status) {
        super.onReadRemoteRssi(gatt, rssi, status);
    }

    @Override
    public void onMtuChanged(BluetoothGatt gatt, int mtu, int status) {
        super.onMtuChanged(gatt, mtu, status);
    }

    @Override
    protected Object clone() throws CloneNotSupportedException {
        return super.clone();
    }

    @Override
    public boolean equals(Object o) {
        return super.equals(o);
    }

    @Override
    protected void finalize() throws Throwable {
        super.finalize();
    }

    @Override
    public int hashCode() {
        return super.hashCode();
    }

    @Override
    public String toString() {
        return super.toString();
    }
};

我在所有调用中添加了一个断点，唯一被击中的是onConnectionStateChange。这个应该是这样工作的吗？我在哪里可以写一个特征或描述，并将其推送到BLE模块？另外，BLE模块(由Arduino控制的HC-10)正在发送数据(用不同的应用程序测试).因此，我希望它也能命中onCharacteristicOnChage方法。我错过了什么？

Answer 1

连接后，Android不知道设备上的任何服务或特性。

因此，必须一旦连接到discoverServices()：

@Override
public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
    if (newState == BluetoothProfile.STATE_CONNECTED) {
        gatt.discoverServices();
    }
}

一旦您得到回调，就可以编写：

@Override
public void onServicesDiscovered(BluetoothGatt gatt, int status) {
    if (status == BluetoothGatt.GATT_SUCCESS) {
        BluetoothGattCharacteristic writeChar = mBluetoothGatt.getService(myServiceUUID)
                    .getCharacteristic(myWriteCharUUID);
        byte[] data = new byte[10];
        writeChar.setValue(data);
        gatt.writeCharacteristic(writeChar);
    }
}