App Switch

request.userAuthenticationEmail = "[email protected]"
request.userPhoneNumber = PayPalPhoneNumber("1", "2223334444")
request.enablePayPalAppSwitch = true

// One-time Checkout — Pay Now.
// USER_ACTION_PAY_NOW presents the "Pay Now" experience: the buyer commits to the payment
// in the PayPal app, and you present the final order status when they return.

val request = PayPalCheckoutRequest(
    hasUserLocationConsent = true,
    amount = "59.00"
).apply {
    enablePayPalAppSwitch = true
    userAuthenticationEmail = "[email protected]"  // Strongly recommended — improves App Switch eligibility
    userAction = PayPalPaymentUserAction.USER_ACTION_PAY_NOW
    shouldOfferPayLater = false  // Set to true to prioritize PayPal Pay Later installment options on the PayPal screen
}

// Use the official Braintree PayPal launcher to present the PayPal button flow
payPalClient.createPaymentAuthRequest(this, request) { authRequest ->
    when (authRequest) {
        is PayPalPaymentAuthRequest.ReadyToLaunch -> {
            pendingRequest = payPalLauncher.launch(this, authRequest)
        }
        is PayPalPaymentAuthRequest.Failure -> handleError(authRequest.error)
    }
}

// In your tokenize callback:
// PayPalResult.Success(nonce) -> createTransaction(nonce.string, "59.00")

class VaultedPaymentActivity : AppCompatActivity() {
    private lateinit var payPalLauncher: PayPalLauncher
    private lateinit var payPalClient: PayPalClient
    
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        
        // PayPalLauncher must be initialized in onCreate
        payPalLauncher = PayPalLauncher()
        
        // can initialize the PayPalClient outside of onCreate if desired
        payPalClient = PayPalClient(
            context = this,
            authorization = "[TOKENIZATION_KEY or CLIENT_TOKEN]",
            appLinkReturnUrl = Uri.parse("https://merchant-app.com"), // Merchant App Link
            "com.merchant.app.deeplink.braintree" // Fallback deep link return url scheme
        )
    }
    
    // ONLY REQUIRED IF YOUR ACTIVITY LAUNCH MODE IS SINGLE_TOP
    override fun onNewIntent(intent: Intent) {
        super.onNewIntent(intent)
        handleReturnToApp(intent)
    }
    
    // ALL OTHER ACTIVITY LAUNCH MODES
    override fun onResume() {
        super.onResume()
        handleReturnToApp(intent)
    }
    
    private fun handleReturnToApp(intent: Intent) {
        // fetch stored PayPalPendingRequest.Success
        val pendingRequest: String = fetchPendingRequestFromPersistantStore()
        when (val paymentAuthResult = payPalLauncher.handleReturnToApp(
            pendingRequest = PayPalPendingRequest.Started(pendingRequest),
            intent = intent
        )) {
            is PayPalPaymentAuthResult.Success -> {
                completePayPalFlow(paymentAuthResult)
                // clear stored PayPalPendingRequest.Success
            }
            is PayPalPaymentAuthResult.NoResult -> {
                // user returned to app without completing PayPal flow, handle accordingly
            }
            is PayPalPaymentAuthResult.Failure -> {
                // handle error case
            }
        }
    }
    
    private fun completePayPalFlow(paymentAuthResult: PayPalPaymentAuthResult.Success) {
        payPalClient.tokenize(paymentAuthResult) { result ->
            when (result) {
                is PayPalResult.Success -> { /* handle result.nonce */ }
                is PayPalResult.Failure -> { /* handle result.error */ }
                is PayPalResult.Cancel -> { /* handle user canceled */ }
            }
        }
    }
    
    private fun onPayPalButtonClick() {
        val payPalVaultRequest = PayPalVaultRequest(
            hasUserLocationConsent = true,
            billingAgreementDescription = "Your agreement description"
        )
        payPalVaultRequest.userAuthenticationEmail = "[email protected]"
        request.userPhoneNumber = PayPalPhoneNumber("1", "2223334444")
        payPalVaultRequest.enablePayPalAppSwitch = true
        
        payPalClient.createPaymentAuthRequest(this, payPalVaultRequest) { paymentAuthRequest ->
            when (paymentAuthRequest) {
                is PayPalPaymentAuthRequest.ReadyToLaunch -> {
                    val pendingRequest = payPalLauncher.launch(this, paymentAuthRequest)
                    when (pendingRequest) {
                        is PayPalPendingRequest.Started -> {/* store pending request */ }
                        is PayPalPendingRequest.Failure -> { /* handle error */ }
                    }
                }
                is PayPalPaymentAuthRequest.Failure -> { /* handle paymentAuthRequest.error */ }
            }
        }
    }
}

// Save Payment Method with Purchase — the buyer pays and saves their PayPal account in one step.
// shouldRequestBillingAgreement = true — buyer consents to save their PayPal account for future use.
// USER_ACTION_PAY_NOW — the buyer commits to the payment in the PayPal app (no review step on your side).

val request = PayPalCheckoutRequest(
    hasUserLocationConsent = true,
    amount = "64.00"
).apply {
    enablePayPalAppSwitch = true
    userAuthenticationEmail = "[email protected]"  // Strongly recommended — improves App Switch eligibility
    userAction = PayPalPaymentUserAction.USER_ACTION_PAY_NOW
    shouldOfferPayLater = false  // Set to true to prioritize PayPal Pay Later installment options on the PayPal screen
    shouldRequestBillingAgreement = true  // Buyer consents to save their PayPal account
    billingAgreementDescription = "Save your PayPal for future purchases"
}

// Use the official Braintree PayPal launcher to present the PayPal button flow
payPalClient.createPaymentAuthRequest(this, request) { authRequest ->
    when (authRequest) {
        is PayPalPaymentAuthRequest.ReadyToLaunch -> {
            pendingRequest = payPalLauncher.launch(this, authRequest)
        }
        is PayPalPaymentAuthRequest.Failure -> handleError(authRequest.error)
    }
}

// In your tokenize callback:
// PayPalResult.Success(nonce) -> createTransactionAndSave(nonce.string, "64.00")
// Server-side: gateway.transaction.sale with storeInVaultOnSuccess: true
// Returns transaction ID + a reusable payment method token for future charges

payPalClient = PayPalClient(
        context = this,
        authorization = "[TOKENIZATION_KEY or CLIENT_TOKEN]",
        appLinkReturnUrl = Uri.parse("https://merchant-app.com"), // Merchant App Link
        "com.merchant.app.deeplink.braintree" // Fallback deep link return url scheme
    )

<intent-filter android:autoVerify="true">
    <action android:name="android.intent.action.VIEW" />
    <category android:name="android.intent.category.DEFAULT" />
    <category android:name="android.intent.category.BROWSABLE" />
    <data android:scheme="https" />
    <data android:host="merchant-app.com" />
    <!-- Required if your App Link URL contains a path -->
    <data android:pathPrefix="/your-app-switch-path" />
</intent-filter>