How to handle Activity.onActivityResult() with Jetpack Compose?

Question

I am trying to implement sign-in hints in my Android app using Jetpack Compose, but this API requires an Activity to work.

fun showPhoneNumberHint(activity: Activity) {
    val hintRequest: HintRequest = HintRequest.Builder()
        .setPhoneNumberIdentifierSupported(true)
        .build()

    val intent = Auth.CredentialsApi.getHintPickerIntent(apiClient, hintRequest)
    val requestCode = 12345

    try {
        startIntentSenderForResult(activity, intent.intentSender, requestCode, null, 0, 0, 0, null)
    } catch (exception: SendIntentException) {
        // Error handling
    }
}

So I guess that I'll have to pass the Activity object all the way down to the Composable where it's needed, which doesn't seem very clean but it should work.

But now the result of the hint will be received in the Activity's onActivityResult() and I'm not sure what the right way is to get it back to the Composable where it's needed.

Is there some clean/standard/alternative way to do this? Preferably I'd just keep all of this logic contained inside the Composable.

Answer 1

I ended up using rememberLauncherForActivityResult in combination with the ActivityResultContracts.StartIntentSenderForResult() contract to listen for the result. This returns a launcher that can be used to start the intent.

Instead of Auth.CredentialsApi, which requires the deprecated GoogleApiClient, I'm now using the Credentials.getClient. For this I still needed an Activity which I got using LocalContext.current.

val phoneNumberHintLauncher = rememberLauncherForActivityResult(
    contract = ActivityResultContracts.StartIntentSenderForResult()
) {
    if (it.resultCode != RESULT_OK) {
        return@rememberLauncherForActivityResult
    }

    val credential: Credential? = it.data?.getParcelableExtra(Credential.EXTRA_KEY)
    val hintResult = credential?.id

    if (hintResult !== null) {
        phoneNumber = hintResult
    }
}

val context = LocalContext.current

LaunchedEffect(Unit) {
    val hintRequest: HintRequest = HintRequest.Builder()
        .setPhoneNumberIdentifierSupported(true)
        .build()

    val phoneNumberHintIntent = Credentials.getClient(context)
        .getHintPickerIntent(hintRequest)

    phoneNumberHintLauncher.launch(
        IntentSenderRequest.Builder(phoneNumberHintIntent)
            .build()
    )
}