Covert lambda result to flow

I have the intention of converting the structure I am currently using to flow. It may sound silly or irrelevant to you.
Let me explain to you the structure:

• I have an object named BleDataSource. For example, it has a function like below.

    fun performConnect(device: BluetoothDevice, result: ((Resource<BleOperationResult>) -> Unit)) {
        enqueueOperation(Connect(device, result))
    }

    fun callback() {
        if ( operation is Connect ) {
           if  ( erroroccured )
               operation.result(Resource.Error("error"))
           else
               operation.result(Resource.Loading())
        }
    }

    fun onetherCallback() {
        if ( operation is Connect ) {
               operation.result(Resource.Success())
        }
    }

• This function saves to the job queue and connects to the device when it’s turn. I can report the current status of the job(For example Loading, Success Or Error) because I also save the result.

• From repository i am using this function as below:

  MEDevel.com: Open-source for Healthcare and Education

  Collecting and validating open-source software for healthcare, education, enterprise, development, medical imaging, medical records, and digital pathology.

  Visit Medevel

    override fun connect(device: BluetoothDevice, result: (Resource<BleOperationResult>) -> Unit) {
        handler.performConnect(device, result)
    }

But I want it to return as flow from the repository.

    override fun connect(device: BluetoothDevice): Flow<Resource<BleOperationResult> {
        handler.performConnect(device) {
        }
    }

How can I do that? (according to recommandation i can also edit the BleDataSource class)

>Solution :

If I understand correctly, it looks like a classic case of converting a "multi-shot" callback function to a flow.

This can be done using callbackFlow:

fun BleDataSource.connect(device: BluetoothDevice): Flow<Resource<BleOperationResult>> = callbackFlow {
    performConnect(device) { res ->
        channel.send(res) // or trySend + error handling
    }
    awaitClose()
}

The problem is that I don’t see a way to unregister the callback from the API you provided. Once you called performConnect with a lambda, it looks like this lambda listener cannot be removed. If there is a way to do that, you should do it in the lambda passed to awaitClose { ... }.