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Google pay Api in Jetpack compose - How to

I can't find resources on the internet on How to achieve the google API integration into an Compose based app.
I need help, especially in the AutoResolveHelper.resolveTask, how to do it in compose.
Thank you for your answers.
(That's mind blowing that there is no more documentation on this API, it's pretty difficult to implement).
Edit :
This is the traditional way to do it ->
private fun requestPayment() {
// Disables the button to prevent multiple clicks.
googlePayButton.isClickable = false
// The price provided to the API should include taxes and shipping.
// This price is not displayed to the user.
val garmentPrice = selectedGarment.getDouble("price")
val priceCents = Math.round(garmentPrice * PaymentsUtil.CENTS.toLong()) + SHIPPING_COST_CENTS
val paymentDataRequestJson = PaymentsUtil.getPaymentDataRequest(priceCents)
if (paymentDataRequestJson == null) {
Log.e("RequestPayment", "Can't fetch payment data request")
return
}
val request = PaymentDataRequest.fromJson(paymentDataRequestJson.toString())
// Since loadPaymentData may show the UI asking the user to select a payment method, we use
// AutoResolveHelper to wait for the user interacting with it. Once completed,
// onActivityResult will be called with the result.
if (request != null) {
AutoResolveHelper.resolveTask(
paymentsClient.loadPaymentData(request), this, LOAD_PAYMENT_DATA_REQUEST_CODE)
}
}
/**
* Handle a resolved activity from the Google Pay payment sheet.
*
* #param requestCode Request code originally supplied to AutoResolveHelper in requestPayment().
* #param resultCode Result code returned by the Google Pay API.
* #param data Intent from the Google Pay API containing payment or error data.
* #see [Getting a result
* from an Activity](https://developer.android.com/training/basics/intents/result)
*/
public override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
when (requestCode) {
// Value passed in AutoResolveHelper
LOAD_PAYMENT_DATA_REQUEST_CODE -> {
when (resultCode) {
RESULT_OK ->
data?.let { intent ->
PaymentData.getFromIntent(intent)?.let(::handlePaymentSuccess)
}
RESULT_CANCELED -> {
// The user cancelled the payment attempt
}
AutoResolveHelper.RESULT_ERROR -> {
AutoResolveHelper.getStatusFromIntent(data)?.let {
handleError(it.statusCode)
}
}
}
// Re-enables the Google Pay payment button.
googlePayButton.isClickable = true
}
}
}

I recently came into this exact same issue. I didn't want to add the code to the activity and make an ugly, unreadable code so I ended up doing this:
In your composable, add this code to the click modifier or whatever:
val task = paymentsClient.loadPaymentData(request)
task.addOnCompleteListener { completedTask ->
if (completedTask.isSuccessful) {
completedTask.result.let{
//Do whatever you want
}
} else {
when (val exception = completedTask.exception) {
is ResolvableApiException -> {
resolvePaymentForResult.launch(
IntentSenderRequest.Builder(exception.resolution).build()
)
}
is ApiException -> {
Log.e("Google Pay API error", "Error code: ${exception.statusCode}, Message: ${exception.message}")
}
else -> {
Log.e("Unexpected non API exception")
}
}
}
}
With resolvePaymentForResult being:
val resolvePaymentForResult = rememberLauncherForActivityResult(ActivityResultContracts.StartIntentSenderForResult()) {
result: ActivityResult ->
when (result.resultCode) {
RESULT_OK ->
result.data?.let { intent ->
PaymentData.getFromIntent(intent)?.let{
//Do whatever you want
}
}
RESULT_CANCELED -> {
// The user cancelled the payment attempt
}
}
}
You can always move paymentsClient.loadPaymentData(request) to your ViewModel if that's your architecture too!
Hope that will clean up your code a little bit more :)

I want my library to start an activity without the main code explictly calling it

I'm working on a library that has a couple of ready-made activities.
So far i have my activities in the library, and in the main app, i call it normally with registerForActivityResult to start it.
this means whoever is using my library would be able to see the whole activity.
what i would like to do, is to have the developer call a method in the library class and ask it to do an action, and in the library that method would on its own start the activity, register it for result, and return the result to the calling class through an interface.
the below is what i tried but it gives me error LifecycleOwner is attempting to register while current state is RESUMED. LifecycleOwners must call register before they are STARTED
private fun launchScannerActivity(activity: FragmentActivity, callback: ScannerCallback) {
val scanResult =
activity.registerForActivityResult(
ActivityResultContracts.StartActivityForResult()
) {
if (it.resultCode == Activity.RESULT_OK) {
callback.onResult(it.data?.getStringExtra("Some Key") ?: "")
} else {
callback.onFail()
}
}
val intent = Intent(activity, ScannerActivity::class.java)
scanResult.launch(intent);
}
why do i need this:
This library would be an SDK for a SAAS product, so we would like to abstract and obfuscate as much of the implementation as possible from our clients.

You can't really communicate between Activities using interfaces, at least not in a way that is somewhat concise and isn't very prone to leaking. What you can do is expose your own Activity result contract. Then your API could be as simple as some of the ones in ActivityResultContracts. You can look at the source code there to see how to implement it.
Maybe something like this:
class ScannerResultContract : ActivityResultContract<Unit, String?>() {
override fun createIntent(context: Context, input: Unit?): Intent {
return Intent(context, ScannerActivity::class.java)
}
override fun parseResult(resultCode: Int, intent: Intent?): String? {
return if (resultCode == Activity.RESULT_OK) {
intent?.getStringExtra("Some Key")
} else {
null
}
}
}
Client usage:
// In activity or fragment:
val getScannerResult = registerForActivityResult(ScannerResultContract()) { resultString ->
if (resultString != null) {
// use it
} else {
// log no result returned
}
}
//elsewhere:
someListener.setOnClickListener {
getScannerResult.launch()
}

Handle multiple errors when the user fill inputs in Kotlin

I'm pretty new with Kotlin (and also I've never coded in Java), and I want to know if there is another way to to this, or if its okay.
To put you in context, I'm working with the Model-View-Presenter. The presenter here, receives the username and login from the login screen, and in order to handle errors (such as empty fields, invalid email), I created an Enum (with possible errors), and then I fill the list of these errors by checking conditions.
Presenter:
fun onLoginButtonClicked(email: String, password: String) {
val errorEnum = mutableListOf<ErrorEnum>()
if (email.isEmpty()) errorEnum.add(ErrorEnum.EMPTY_EMAIL)
if (password.isEmpty()) errorEnum.add(ErrorEnum.EMPTY_PASSWORD)
if (email.isNotEmpty() && !Patterns.EMAIL_ADDRESS.matcher(email).matches()) errorEnum.add(ErrorEnum.INVALID_EMAIL)
if (errorEnum.isEmpty()) {
userSession.email = email
userSession.password = password
view?.goToViewPager(email)
} else {
view?.checkErrors(errorEnum)
}
}
After that, the fragment reflects on the view the errors, iterating through the list.
Fragment:
override fun checkErrors(Errors: MutableList<ErrorEnum>) {
Errors.forEach {
when (it) {
ErrorEnum.EMPTY_PASSWORD -> binding.password.error = getString(R.string.login_alert_input)
ErrorEnum.INVALID_EMAIL -> binding.email.error = getString(R.string.login_alert_bad_email)
ErrorEnum.EMPTY_EMAIL -> binding.email.error = getString(R.string.login_alert_input)
}
}
}

Clearly, you are doing redundant work here, first your are building up List and then passing the List to View and again View is doing some work to iterate and compare, instead you can have separate methods in view to handle each without comparison and call them directly
override fun showEmailInvalidError() {
binding.password.error = getString(R.string.login_alert_input)
}
override fun showEmptyEmailError() {
binding.email.error = getString(R.string.login_alert_input)
}
override fun showEmptyPasswordError() {
binding.email.error = getString(R.string.login_alert_bad_email)
}
In presenter
fun onLoginButtonClicked(email: String, password: String) {
if(email.isEmpty()) view?.showEmptyEmailError()
if(password.isEmpty()) view?.showEmptyPasswordError()
if(email.isNotEmpty() && !Patterns.EMAIL_ADDRESS.matcher(email).matches())
view?.showEmailInvalidError()
if(errorEnum.isEmpty()) {
userSession.email = email
userSession.password = password
view?.goToViewPager(email)
}else {
view?.checkErrors(errorEnum)
}
}

queryPurchases() returns an empty list

I have implemented the Billing library in order to have in-app products in my app. I can make a successful purchase and everything works fine. If I try to make a purchase again, I get the response "Product already owned" which shows that the purchase is fine. I am using as productID the test id: "android.test.purchased"
Moreover, in the Main's Activity onResume() method, I call the queryPurchases() method in order to restore the product in case the user deletes the app and re-installs it. However, this method returns an empty purchases list although the response code is OK.
This is the way I am using the method:
private fun startServiceConnectionIfNeeded(executeOnSuccess: Runnable?) {
if (mBillingClient.isReady) {
executeOnSuccess?.run()
} else {
mBillingClient.startConnection(object : BillingClientStateListener {
override fun onBillingSetupFinished(#BillingClient.BillingResponse billingResponse: Int) {
if (billingResponse == BillingClient.BillingResponse.OK) {
Log.i(TAG, "onBillingSetupFinished() response: $billingResponse")
executeOnSuccess?.run()
} else {
Log.w(TAG, "onBillingSetupFinished() error code: $billingResponse")
}
}
override fun onBillingServiceDisconnected() {
Log.w(TAG, "onBillingServiceDisconnected()")
}
})
}
}
// I call this method in Main's onResume()
fun updateBillingSharedPreferencesKey() {
val executeOnConnectedService = Runnable {
val purchasesResult = mBillingClient.queryPurchases(BillingClient.SkuType.INAPP)
val purchasesList = purchasesResult?.purchasesList
purchasesList?.let {
// this list is always empty, although I have a valid product
for (purchase in it) {
// I never enter this loop to handle the product functionality
Log.d(TAG, "purchase.sku = ${purchase?.sku}")
}
}
}
startServiceConnectionIfNeeded(executeOnConnectedService)
}
Am I doing something wrong? The service connection and the response code is ok.
How should I call the queryPurchases() method to get my valid in-app product?

Get Android activity result in Flutter

I have a thirdparty Android control that can't be used in Flutter directly. I put it in an Android activity. Then, using information from https://flutter.io/docs/development/platform-integration/platform-channels#step-3b-add-an-android-platform-specific-implementation-using-kotlin, I can successfully launch that activity and perform some actions there. The only part that doesn't work is sending results back from the activity.
Flutter code:
void showDialog() async
{
try {
final Map<String, List<double>> result = await platform.invokeMethod('show_dialog',
<String, String>{
'address': widget.user.address
});
widget.user.address = result.keys.toList()[0];
} on PlatformException catch (e) {
print('Failed to pick address: ${e.message}.');
}
}
Android code:
class MainActivity: FlutterActivity() {
private val CHANNEL = "dialog"
private lateinit var _result: MethodChannel.Result
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
GeneratedPluginRegistrant.registerWith(this)
MethodChannel(flutterView, CHANNEL).setMethodCallHandler { call, result ->
if (call.method == "show_dialog") {
_result = result
val intent = Intent(this#MainActivity, DialogActivity::class.java)
intent.putExtra("address", call.argument<String>("address"))
startActivityForResult(intent, 9689)
}
else result.notImplemented()
}
}
override fun onActivityResult(requestCode: Int, result: Int, intent: Intent?) {
if(requestCode != 9689)
return super.onActivityResult(requestCode, result, intent)
if (result == Activity.RESULT_OK) {
_result.success(mapOf(intent!!.getStringExtra("address") to
listOf(intent.getDoubleExtra("latitude", 0.0),
intent.getDoubleExtra("longitude", 0.0))))
}
else
_result.success(null)
}
}
What's the problem? Breakpoint on the line widget.user.address = result.keys.toList()[0]; is never reached, suggesting the result is never sent back.

Turns out the code was almost correct. The Android side didn't need any changes, but on the Flutter side I had to make this change:
turn
final Map<String, List<double>> result = await platform.invokeMethod(
into
final result = await platform.invokeMethod(
i. e. simply remove explicit type from the variable, because the return value of platform.invokeMethod was some kind of an internal hash map (in particular, it's name started with an underscore) rather than that of Map as specified. Flutter didn't show any errors in the console output, because for some reason it only captures Android log with debugger attached to the Android part of the application, and once I figured how to debug Android code in Android Studio, I immediately found the reason.