Implement Google Play Billing Library version 2

Question

Google published a brand new version to handle the payments in Android but after searching quite a while I cannot find a single example or tutorial from someone who succeeded im

Answer 1

Here is my implementation using billing 2.1.0 in Kotlin. You can easily convert it to Java if you see the whole picture (that's why I'm pasting you the entire activity).

class GoPremiumActivity : AppCompatActivity(), PurchasesUpdatedListener, AcknowledgePurchaseResponseListener {

    private lateinit var billingClient: BillingClient
    private val skuList = listOf(CStr.PRODUCT_ADS_REMOVE.value)
    private var skuDetails: SkuDetails? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.go_premium)
        supportActionBar?.setDisplayHomeAsUpEnabled(true)
        setupBillingClient()

        purchaseButton.setOnClickListener {
            val flowParams = BillingFlowParams.newBuilder()
                    .setSkuDetails(skuDetails)
                    .build()
            billingClient.launchBillingFlow(this@GoPremiumActivity, flowParams)
        }
    }


    private fun setupBillingClient() {
        billingClient = BillingClient
                .newBuilder(this@GoPremiumActivity)
                .enablePendingPurchases()
                .setListener(this@GoPremiumActivity)
                .build()

        billingClient.startConnection(object : BillingClientStateListener {
            override fun onBillingSetupFinished(billingResult: BillingResult?) {
                if (billingResult?.responseCode == BillingClient.BillingResponseCode.OK) {
                    getAvailableProducts()

                    val purchasesResult = billingClient.queryPurchases(BillingClient.SkuType.INAPP)
                    val purchase = purchasesResult.purchasesList.firstOrNull { it.sku == CStr.PRODUCT_ADS_REMOVE.value}
                    if (purchase?.isAcknowledged == true) {
                        Global.prefs.adsRemovalPurchased = true
                        finish()
                    }
                } else {
                    showGeneralError()
                }
            }

            override fun onBillingServiceDisconnected() {
                /*DO NOTHING*/
            }
        })
    }

    fun getAvailableProducts() {
        if (billingClient.isReady) {
            val params = SkuDetailsParams
                    .newBuilder()
                    .setSkusList(skuList)
                    .setType(BillingClient.SkuType.INAPP)
                    .build()
            billingClient.querySkuDetailsAsync(params) { responseCode, skuDetailsList ->
                if (responseCode.responseCode == BillingClient.BillingResponseCode.OK) {
                    skuDetails = skuDetailsList.firstOrNull()
                    skuDetails?.let {
                        purchaseButton.text = String.format("BUY %s", it.price)
                        showSuccessOrError(success = true)
                    } ?: run {
                        showSuccessOrError(success = false)
                    }
                } else {
                    showGeneralError()
                }
            }
        } else {
            showGeneralError()
        }
    }

    override fun onPurchasesUpdated(billingResult: BillingResult?, purchases: MutableList?) {
        if (billingResult?.responseCode == BillingClient.BillingResponseCode.OK && purchases != null) {
            val purchase = purchases.firstOrNull { it.sku == CStr.PRODUCT_ADS_REMOVE.value}
            if (purchase?.purchaseState == Purchase.PurchaseState.PURCHASED) {
                if (!purchase.isAcknowledged) {
                    val acknowledgePurchaseParams = AcknowledgePurchaseParams.newBuilder()
                            .setPurchaseToken(purchase.purchaseToken)
                            .build()
                    billingClient.acknowledgePurchase(acknowledgePurchaseParams, this@GoPremiumActivity)
                }
            }
        } else if (billingResult?.responseCode == BillingClient.BillingResponseCode.ITEM_ALREADY_OWNED) {
            Global.prefs.adsRemovalPurchased = true
            finish()
        } else {
            Global.prefs.adsRemovalPurchased = false
            showSuccessOrError(success = true)
        }
    }

    override fun onAcknowledgePurchaseResponse(billingResult: BillingResult?) {
        if (billingResult?.responseCode == BillingClient.BillingResponseCode.OK) {
            showThankYouDialog(this@GoPremiumActivity)
            Global.prefs.adsRemovalPurchased = true
        }
    }

    private fun showSuccessOrError(success: Boolean) {
        purchaseProgressBar.visibility = View.GONE
        if (success) {
            purchaseButton.visibility = View.VISIBLE
        } else {
            purchaseUnavailable.visibility = View.VISIBLE
        }
    }

    private fun showGeneralError() {
        purchaseProgressBar.visibility = View.GONE
        purchaseUnavailable.visibility = View.VISIBLE
    }

    companion object {
        fun newIntent(context: Context): Intent {
            return Intent(context, GoPremiumActivity::class.java)
        }
    }

    override fun onSupportNavigateUp(): Boolean {
        finish()
        return true
    }

    public override fun onDestroy() {
        super.onDestroy()
    }

    override fun onPause() {
        super.onPause()
        if (isFinishing) {
            finish()
        }
    }

    private fun showThankYouDialog(context: Context) {
        //Show dialog
    }
}

I can remove it if you specifically want it in Java.