Trouble getting the libaries to work on Android

[B0nusduck]

i'm using 32feet.NET - Legacy (v3.x) version this libary to do a bluetooth controller in my .net maui project, the code run well on window but when i compile and run in on mobile, it always fail to initialize the BluetoothClient variable, throwing a vauge PlatformNotSupportedException with no description.

Here are the things that i have tried:
-add required android premission:

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission` android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />

• changed the used libary to InTheHand.Net.Bluetooth - Bluetooth Classic (v4.x)

result: success fully initialize BluetoothClient and connect to remote host but the rersulting BluetoothClient is not usable with the BluetoothClient.Client show Client = {"Operation is not supported on this platform."} when inspecting.

• changed the used libary to InTheHand.BluetoothLE - Bluetooth Low Energy (v4.x).

result: im unable to find any document or example on how to use this libary and the code wont work when i remove the other libary so i assume that it is a complementary libary for the 32feet.NET - Legacy (v3.x) and InTheHand.Net.Bluetooth - Bluetooth Classic (v4.x). It still not work even when install allong with them, so if anyone know any example project or how to use it, i would be very apreciated for your help.

• delete obj and bin + rebuild using 32feet.NET - Legacy (v3.x), InTheHand.Net.Bluetooth - Bluetooth Classic (v4.x) and InTheHand.BluetoothLE - Bluetooth Low Energy (v4.x)

result: same result as the preveous results.

Additional infromation:
-here are the call stack that i've manage to get from the 32feet.NET - Legacy (v3.x) attemp:

{System.PlatformNotSupportedException: No supported Bluetooth protocol stack found.
at InTheHand.Net.Bluetooth.Factory.BluetoothFactory.GetStacks_inLock()
at InTheHand.Net.Bluetooth.Factory.BluetoothFactory.get_Factories()
at InTheHand.Net.Bluetooth.Factory.BluetoothFactory.get_Factory()
at InTheHand.Net.Sockets.BluetoothClient..ctor()
at bluetoothController.MainPage.GetMainclient()

-I the reason that is use the Legacy (v3.x) libary is because i was following this guide regarding sending and reciving data via bluetooth

-during my 32feet.NET - Legacy (v3.x) attemps i notice a warning regarding this libary in the androd dependency, i know that it might be the cause but i can't open and read the warning, so i instead tried to go to the nuget installation page but notice nothing usefull. I've also tried looking for any other warning in the other two latest libary but found no warning in the solution explorer dependencies.

-i've read more about other issue and discussion in this repository and found that issue #458 and #187 does have some similarity to the prolem i encounterd though the only similarity is the PlatformNotSupportedException and nothing else so im not sure that it would be applicable

-target environment:

.net 9.0 for both android and window
window 10
android 13 (redmi)

-Finally the code i use, these three function are the all of the bluetooth related code in my project, and all of my attemp mentioned earlyer are done on these code with minimal changes:

private BluetoothClient? client = new BluetoothClient()
client = await ConnectBluetooth() 
public async Task<BluetoothClient?> ConnectBluetooth()
{
    BluetoothAddress deviceAddress = BluetoothAddress.Parse("target device address");

    try
    {
        Mainclient?.Connect(deviceAddress, BluetoothService.SerialPort);


        if (Mainclient != null && !Mainclient.Connected)
        {
            await DisplayAlert("connection failed", null, "ok");
            return null;
        }
        else
        {
            return Mainclient;
        }
    }
    catch (SocketException ex)
    {
        await AlertException(ex);
        return null;
    }
    catch (Exception ex)
    {
        await AlertException(ex);
        return null;
    }
}
public async Task<bool> SentData(BluetoothClient? client, string data)
{
    try
    {
        if (client != null && client.Connected)
        {
            NetworkStream stream = client.GetStream();
            byte[] dataBytes = Encoding.UTF8.GetBytes(data);
            stream.Write(dataBytes);
            return true;
        }
        else
        {
            await DisplayAlert("connection lost", "try reconnecting to the vehicle", "ok");
            return false;
        }
    }
    catch (Exception ex)
    {
        await AlertException(ex);
        return false;
    }
}
public async Task<string?> GetData(BluetoothClient? client)
{
    try
    {

        if (client != null && client.Connected)
        {
            NetworkStream stream = client.GetStream();
            byte[] receiveBuffer = new byte[1024];
            int bytesRead = stream.Read(receiveBuffer, 0, receiveBuffer.Length);
            string receivedData = Encoding.UTF8.GetString(receiveBuffer, 0, bytesRead);

            return receivedData;
        }
        else
        {
            await DisplayAlert("connection lost", "try reconnecting to the vehicle", "ok");
            return null;
        }
    }
    catch (Exception ex)
    {
        await AlertException(ex);
        return null;
    }
}

That's everything that I've manage to know about this problem, since this is my first time using this libary and also my first time writing a coding question so the quality of this question might be poor so sorry for that in advance. Any help or suggestion would be extremely apreciated.

[peterfoot]

The legacy one won't work in modern .NET. You should be able to do everything you need in v4. The Client property is for platforms which use System.Net.Sockets which Android does not. However you can get the Stream for the client and use that to read and write. Note also that most platforms buffer when you write to a stream so you will want to call Flush() (or FlushAsync()) to ensure it is sent to the device.