Android app

Applies to: Mini Card Reader, Pocket Card Terminal connected via Bluetooth or USB to the Viva Wallet POS app for Android.

The Viva Wallet POS app for Android can receive requests for initiating transactions from third-party apps installed on the same Android mobile device. Communication with the card terminal app is done by using Android intents. The client app creates an intent with parameters and starts the card terminal app’s pay activity. When the card terminal app’s pay activity finishes it returns the result to the caller app.

A sample app is also available for download from our public GitHub account. It demonstrates the inter-app communication ability and contains all the necessary Gradle build files.

Messages

The client app must implement a mechanism to send messages using Android intents and URI calls and to receive the result in a custom URI callback. Overall the following messages are available:

• Sale request originating from the client app to initiate a request for a new Sale transaction.
• Sale response originating from the card terminal app to return the result of a Sale transaction.
• Cancel request originating from the client app to initiate a request for a Cancel transaction.
• Cancel response originating from the card terminal app to return the result of a Cancel transaction.
• Abort request originating from the client app to abort (if possible) the last Sale request.
• Abort response originating from the card terminal app to return the result of an Abort request.
• Printing settings request originating from the client app to change the Printing Settings.
• Printing settings response originating from the Card terminal app to return the result of a Printing settings request.
• Foreground request originating from the client app to bring Card terminal app to foreground.

Callback activity

The client app must provide a callback activity declare in AndroidManifest.xml, in order to receive the response results.

<activity
          android:name="com.example.URLResponseActivity"
          android:label="Payment Result">
            <intent-filter>
                <action android:name="android.intent.action.VIEW"/>
                <action android:name="com.example.URLResponseActivity"/>
                <category android:name="android.intent.category.DEFAULT"/>
                <category android:name="android.intent.category.BROWSABLE"/>
                <!-- Provide your own scheme here and reference it when you send a message -->
                 <data
                   android:scheme="mycallbackscheme"
                   android:host="result"/>
            </intent-filter>
        </activity>

Sale request

For a typical sale request the client app must provide the following information:

Field	Description	Example	Card terminal support
scheme	The Viva custom URL scheme, the host and the version.	'vivapayclient://pay/v1'
merchantKey	The merchant's key. For successful validation, should not be empty.	'SG23323424EXS3'
appId	The client app ID. For successful validation, should not be empty.	'com.example.myapp'
action	Sale transaction. For successful validation, should not be empty.	'sale'
clientTransactionId	A unique transaction ID transmitted to the host for storage with the transaction. Note that this value will be provided in the Merchant Reference field provided in the sales export response.	'12345678901234567890123456789012'
amount	Amount in cents without any decimal digits. If action is sale or bill payment, must not be empty. Must be integer and bigger than zero.	'1200' = 12 euro
tipAmount	How much of the amount in cents is considered as tip without any decimal digits.	'200' = 2 euro
withInstallments	Enable installments.	'true'
preferredInstallments	Number of preferred installments. If the number is between the allowed range and the card supports installments then the flow complete without any prompt for installments. If the number is 0 or > max allowed number of installments then the user will be prompt to enter the number in the app. If the card does not support installments then the app will request from the user how to proceed with the flow. If withInstallments is true preferredInstallments must be integer and not empty.	'10'
callback	The URI callback that will handle the result. For successful validation, should not be empty.	'mycallbackscheme://result'
show_receipt	A flag indicating if the receipt and transaction result will be shown. If true both transaction result and receipt will be shown. If false receipt will not be shown and result will be shown if show_transaction_result is true.	'true'
show_transaction_result	A flag indicating whether transaction result will be shown.	'true'
show_rating	A flag indicating if the rating flow will be shown.	'true'
ISV_amount	The amount tha ISV charges.	'10'
ISV_clientId	The ID of the ISV client. It is mandatory that if client ID is provided the ISV_amount and ISV_clientSecret parameters should be provided too.	'qwerty123456'
ISV_clientSecret	The secret of the ISV client.	'qwerty123456'
ISV_sourceCode	The reseller source code of the ISV.	'qwerty123456'

The above information elements must create a URI call, i.e.

Intent payIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(
                        "vivapayclient://pay/v1"
                                + "?merchantKey="MY_MERCHANT_KEY""
                                + "&appId=com.example.myapp"
                                + "&action=sale"
                                + "&clientTransactionId=1234567801234"
                                + "&amount=1200"
                                + "&tipAmount=200"
                                + "&show_receipt="+true
                                + "&show_transaction_result="+true
                                + "&show_rating="+true
                                + "&tipAmount="+true
                                + "&withInstallments="+10
                                + "&ISV_amount="+10
                                + "&ISV_clientId=qwerty123456"
                                + "&ISV_clientSecret=qwerty123456"
                                + "&ISV_sourceCode=qwerty123456"
                                + "&callback=mycallbackscheme://result"));

payIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

payIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
                startActivity(payIntent);

The result is received as a URI in the callback activity intent:

Uri result = getIntent().getData()

Sale response

After executing a sale transaction the card terminal app responds with a sale response result to indicate if the transaction has been approved or not.

The result is received as a URI in the callback activity intent:

Uri result = getIntent().getData()`

The table below summarises the contents of an approved response.

Field	Description	Example	Card terminal support
callback	The URI callback that will handle the result.	'mycallbackscheme://result'
status	The status of the transaction.	'success'
message	A string containing information about the transaction status.	'Transaction successful'
action	Sale transaction.	'sale'
clientTransactionId	The client transaction ID.	'12345678901234567890123456789012'
amount	The amount in cents without any decimal digits. If action is cancel and amount is not empty must be integer and bigger than zero.	'1200' = 12 euro
tipAmount	How much of the amount in cents is considered as tip without any decimal digits.	'200' = 2 euro
verificationMethod	The verification method used.	'CHIP-PIN'
rrn	The retrieval reference number of the transaction RRN.	'123456833121'
cardType	The card type.	'VISA'
accountNumber	The card number masked. Note that only the 6 first and the 4 last digits are provided. All other digits are masked with stars.	'479275\*\*\*\*\*\*9999'
referenceNumber	A 6-digit number indicating the transaction's STAN number.	'833121'
authorisationCode	A 6-digit number indicating the transaction's Authorisation code provided by the host.	'690882'
tid	A 12 character string indicating the terminal's TID number.	' 16016684'
orderCode	The order code.	' 9256110059000200'
shortOrderCode	10-digit integer.	'1234567890'
installments	Number of installments.	' 10'
transactionDate	The transaction date in ISO 8601 format.	'2019-09-13T12:14:19.8703452+03:00'
transactionId	A unique identifier for the transaction.	'a78e045c-49c3-4743-9071-f1e0ed71810c'
ISV_amount	The amount that the ISV charges.	'10'
ISV_clientId	The ID of the ISV client.	'qwerty123456'
ISV_clientSecret	The secret of the ISV client.	'qwerty123456'
ISV_sourceCode	The reseller source code of the ISV.	'qwerty123456'

A sale response result for an approved transaction looks as follows:

mycallbackscheme://result?status=success&message=Transaction successful&action=sale&clientTransactionId=1234567801234&amount=1200&tipAmount=0&verificationMethod=CONTACTLESS - NO CVM&rrn=107715996464&cardType=Debit Mastercard&referenceNumber=996464&accountNumber=537488******9666&authorisationCode=006593&tid=16000223&orderCode=1077172694000223&shortOrderCode=1077172694&transactionDate=2021-03-18T17:07:51.1888432+02:00&transactionId=2161282c-3989-4089-80f1-2ac555dc5f63

It is expected that certain transactions will fail for various reasons. A sale response result for a failed transaction looks as follows:

mycallbackscheme://result?status=fail&message=(-12) TRANSACTION_DECLINED_BY_SERVER&action=sale&clientTransactionId=1234567801234&amount=101&tipAmount=0&verificationMethod=CONTACTLESS - NO CVM&rrn=107715996469&cardType=Debit Mastercard&referenceNumber=996469&accountNumber=537488******9666&tid=16000223&orderCode=1077172696000223&shortOrderCode=1077172696&transactionDate=2021-03-18T17:09:13.1917889+02:00&transactionId=3ca278e7-0679-411e-8279-ebb29ee519b2

The structure of the message is the same as in the case of an approved transaction. Fields such as referenceNumber and authorisationCode may not have values since there is no STAN code available, nor an authorisation code.

Cancel request

For a typical cancel request, or refund, the client app must provide the following information:

Field	Description	Example	Card terminal support
scheme	The Viva's custom URL scheme, the host and the version.	'vivapayclient://pay/v1'
merchantKey	The merchant's key. For successful validation, should not be empty.	'SG23323424EXS3'
appId	The client app ID. For successful validation, should not be empty.	'com.example.myapp'
action	Cancel transaction. For successful validation, should not be empty.	'cancel'
referenceNumber	The STAN number of the transaction to be cancelled. If empty, after card presentment, the app will provide a list of the last 3 transactions made with the presented card, allowing the user to select the transaction to be canceled. If action is cancel and if not empty should be integer bigger than zero.
callback	The URI callback that will handle the result. For successful validation, should not be empty.	'mycallbackscheme://result'
orderCode	If not empty should be integer bigger than zero and length 16.	'1020304050607080'
shortOrderCode	If not empty should be integer bigger than zero and length 10.	'1234567890'
txnDateFrom	If action is cancel and if not empty should be in "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'" format.	'2021-03-18T14:42:53.341Z'
txnDateTo	If action is cancel and if not empty should be in "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'" format, txnDateFrom should be provided and txnDateTo should be after txnDateFrom.	`2021-03-19T14:42:53.341Z`
show_receipt	A flag indicating if the receipt and transaction result will be shown. If true both transaction result and receipt will be shown. If false receipt will not be shown and result will be shown if show_transaction_result is true.	'true'
show_transaction_result	A flag indicating if transaction result will be shown.	'true'
show_rating	A flag indicating if the rating flow will be shown.	'true'

The above information elements must create a URI call, i.e.

Intent payIntent = new Intent(Intent.ACTION_VIEW, Uri.parse( "vivapayclient://pay/v1"
				+ "?merchantKey="MY_MERCHANT_KEY"
				+ "&appId=com.example.myapp"
				+ "&action=cancel"
				+ "&referenceNumber=123456"
				+ "&callback=mycallbackscheme://result"
				+ "&orderCode=1020304050607080"
				+ "&shortOrderCode=1234567890"
				+ "&txnDateFrom=2021-03-18T14:42:53.341Z"
				+ "&txnDateTo=2021-03-19T14:42:53.341Z"
				+ "&amount=100"
				+ "&show_receipt="+true
				+ "&show_transaction_result="+true
				+ "&show_rating="+true ));


payIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
payIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
payIntent.addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
payIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
                startActivity(payIntent);

The result is received as a URI in the callback activity intent:

Uri result = getIntent().getData()

Cancel response

After executing a cancel transaction, or refund, the card terminal app responds with a cancel response result to indicate if the refund has been approved or not.

The result is received as a URI in the callback activity intent:

Uri result = getIntent().getData()

The table below summarises the contents of an approved response.

Field	Description	Example	Card terminal support
callback	The URI callback that will handle the result.	'mycallbackscheme://result'
status	The status of the transaction	'success'
message	A string containing information about the transaction status.	'Transaction successful'
action	Cancel transaction.	'cancel'
amount	The amount in cents without any decimal digits.	'1200' = 12 euro
cardType	The card type.	'VISA'
accountNumber	The card number. Note that only the 6 first and the 4 last digits are provided. All other digits are masked with stars.	'479275\*\*\*\*\*\*9999'
tid	A 12-character string indicating the terminal's TID number.	'16016684'
orderCode	16-digit integer.	'1020304050607080'
shortOrderCode	10-digit integer.	'1234567890'
transactionDate	The transaction date in ISO 8601 format.	'2019-09-13T12:14:19.8703452+03:00'
transactionId	A unique identifier for the transaction.	'a78e045c-49c3-4743-9071-f1e0ed71810c'

A cancel response result for an approved refund looks as follows:

mycallbackscheme://result?status=success&message=Transaction successful&action=cancel&clientTransactionId=1234567801234&amount=1200&tipAmount=0&verificationMethod=CONTACTLESS - NO CVM&rrn=107715996464&cardType=MASTERCARD&referenceNumber=996471&accountNumber=************9666&tid=16000223&orderCode=1077172694000223&shortOrderCode=1077172694&transactionDate=2021-03-18T17:09:50.8747721+02:00&transactionId=5f3ecbbe-d2da-4e59-9d38-610fddd79c73

It is expected that certain transactions will fail for various reasons. A cancel response result for a failed refund looks as follows:

`mycallbackscheme://result?status=fail&message=(-24) REFUND_INVALID_AMOUNT&action=&amount=10000&tipAmount=0&verificationMethod=CONTACTLESS - NO CVM&cardType=Debit Mastercard&referenceNumber=0&accountNumber=537488******9666&tid=16000223&orderCode=0&shortOrderCode=0

The structure of the message is the same as in the case of an approved refund.

Abort request

Using abort action user tries to abort a transaction he started from the third-party app. Abort will not always succeed as in some cases it is not possible to abort the transaction. For a typical abort transaction request, the client app must provide the following information:

Field	Description	Example	Card terminal support
scheme	The Viva's custom URL scheme, the host and the version.	'vivapayclient://pay/v1'
merchantKey	The merchant's key. For successful validation, should not be empty.	'SG23323424EXS3'
appId	The client app ID. For successful validation, should not be empty.	'com.example.myapp'
action	Cancel transaction. For successful validation, should not be empty.	'abort'
callback	The URI callback that will handle the result. For successful validation, should not be empty.	'mycallbackscheme://result'

The above information elements must create a URI call, i.e.

Intent payIntent = new Intent(Intent.ACTION_VIEW, Uri.parse( "vivapayclient://pay/v1"
			+ "?merchantKey=MY_MERCHANT_KEY"
			+ "&appId=com.example.myapp"
			+ "&action=abort"
			+ "&referenceNumber=123456"
			+ "&callback=mycallbackscheme://result"));


payIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
payIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
startActivity(payIntent);

The result is received as a URI in the callback activity intent:

Uri result = getIntent().getData()

Abort response

After executing an abort transaction, the Card Terminal App responds with an abort response result to indicate if the abort request has been successful or not. Also, we should state that the response from the abort action is actually a response of a failed transaction.

The result is received as a URI in the callback activity intent:

Uri result = getIntent().getData()

The table below summarises the contents of an approved response.

Field	Description	Example	Card terminal support
callback	The URI callback that will handle the result.	'mycallbackscheme://result'
status	The status of the transaction.	'success'
message	A string containing information about the transaction status.	'Transaction successful'
action	Cancel transaction.	'abort'

A cancel response result for an approved refund looks as follows:

mycallbackscheme://result?status=fail&message=(-57) ABORTED&action=ABORT&amount=10&tipAmount=0

It is expected that if we have not started a transaction the Abort action will respond (-55) NOTHING_TO_ABORT. A failed Abort action response looks as follows:

mycallbackscheme://result?status=fail&message=(-55) NOTHING_TO_ABORT&action=ABORT

In some cases (when the transaction has been sent to server for approval / user selected payment with QR) the transaction cannot be aborted, and the Card Terminal app will not send the Abort response.

Printing settings request

Using set printing options action, the user can apply changes to printing settings of the POS application from a third-party app. For a typical set printing options request, the client app must provide the following information:

Field	Description	Example	Card terminal support
scheme	The Viva's custom URL scheme, the host and the version.	'vivapayclient://pay/v1'
merchantKey	The merchant's key. For successful validation, should not be empty.	'SG23323424EXS3'
appId	The client app ID. For successful validation, should not be empty.	'com.example.myapp'
action	Set printing settings. For successful validation, should not be empty.	'set_printing_settings'
businessDescriptionEnabled	A flag indicating whether the business description identifier will be printed on the receipt	'true'
businessDescriptionType	The business description identifier that will be printed on the receipt if it is enabled. For successful validation, should be one of the following values: 'businessName', 'tradeName', 'storeName'	'businessName'
printLogoOnMerchantReceipt	A flag indicating whether the logo will be printed on the receipt of the merchant	'true'
printVATOnMerchantReceipt	A flag indicating whether the vat number will be printed on the receipt of the merchant	'true'
isBarcodeEnabled	A flag indicating whether the barcode will be printed on the receipt	'true'
printAddressOnReceipt	A flag indicating whether the address will be printed on the receipt	'true'
isMerchantReceiptEnabled	A flag indicating whether the receipt of the merchant will be printed	'true'
isCustomerReceiptEnabled	A flag indicating whether the receipt of the customer will be printed	'true'
callback	The URI callback that will handle the result. For successful validation, should not be empty.	'mycallbackscheme://result'

The above information elements must create a URI call, i.e.

String reqStr = "vivapayclient://pay/v1"
		+ "?merchantKey="MY_MERCHANT_KEY"
		+ "&appId=com.example.myapp"
		+ "&action=set_printing_settings"
		+ "&callback=mycallbackscheme://result"
		+ "&businessDescriptionEnabled=true"
		+ "&businessDescriptionType=businessName"
		+ "&printLogoOnMerchantReceipt=true"
		+ "&printVATOnMerchantReceipt=true"
		+ "&isBarcodeEnabled=true"
		+ "&printAddressOnReceipt=true"
		+ "&isMerchantReceiptEnabled=true"
		+ "&isCustomerReceiptEnabled=true";

Intent payIntent = new Intent(Intent.ACTION_VIEW, Uri.parse( reqStr));
payIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
payIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
startActivity(payIntent);

The result is received as a URI in the callback activity intent:

Uri result = getIntent().getData();

Printing settings response

After executing an abort transaction, the Card Terminal App responds with an abort response result to indicate if the abort request has been successful or not. The response from the abort action is actually the response of a failed transaction.

The result is received as a URI in the callback activity intent:

Uri result = getIntent().getData();

The table below summarises the contents of an approved response.

Field	Description	Example	Card terminal support
callback	The URI callback that will handle the result.	'mycallbackscheme://result'
status	The status of the transaction	'success'
message	A string containing information about the transaction status.	'Transaction successful'
action	Set printing settings. For successful validation, should not be empty.	'set_printing_settings'
businessDescriptionEnabled	A flag indicating whether the business description identifier will be printed on the receipt	'true'
businessDescriptionType	The business description identifier that will be printed on the receipt if it is enabled. For successful validation, should be one of the following values: 'businessName', 'tradeName', 'storeName'	'businessName'
printLogoOnMerchantReceipt	A flag indicating whether the logo will be printed on the receipt of the merchant	'true'
printVATOnMerchantReceipt	A flag indicating whether the vat number will be printed on the receipt of the merchant	'true'
isBarcodeEnabled	A flag indicating whether the barcode will be printed on the receipt	'true'
printAddressOnReceipt	A flag indicating whether the address will be printed on the receipt	'true'
isMerchantReceiptEnabled	A flag indicating whether the receipt of the merchant will be printed	'true'
isCustomerReceiptEnabled	A flag indicating whether the receipt of the customer will be printed	'true'

A cancel response result for an approved refund looks as follows:

mycallbackscheme://result?status=success&message=Printing settings updated&action=set_printing_settings&businessDescriptionType=businessName&printLogoOnMerchantReceipt=false&printVATOnMerchantReceipt=false&isBarcodeEnabled=false&businessDescriptionEnabled=false&printAddressOnReceipt=false&isMerchantReceiptEnabled=false&isCustomerReceiptEnabled=false

Foreground request

Using the foreground action, the user can bring to foreground Android POS App from a third-party app. For a typical foreground request, the client app must provide the following information:

Field	Description	Example	Card terminal support
scheme	The Viva's custom URL scheme, the host and the version.	'vivapayclient://pay/v1'
merchantKey	The merchant's key. For successful validation, should not be empty.	'SG23323424EXS3'
appId	The client app ID. For successful validation, should not be empty.	'com.example.myapp'
action	Set printing settings. For successful validation, should not be empty.	'set_printing_settings'
callback	The URI callback that will handle the result. For successful validation, should not be empty.	'mycallbackscheme://result'

This action does not send back a response.

The above information elements must create a URI call, i.e.

String reqStr = "vivapayclient://pay/v1"
		+ "?merchantKey="MY_MERCHANT_KEY"
		+ "&appId=com.example.myapp"
		+ "&action= foreground"
		+ "&callback=mycallbackscheme://result";

Intent payIntent = new Intent(Intent.ACTION_VIEW, Uri.parse( reqStr));
payIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
payIntent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
startActivity(payIntent);

Key to card terminal product categories

To understand the icons used in the above tables, see the below table.

Product category	Terminal models	Icon
Android Card Terminals	Android Card Terminal Ethernet, Android Card Terminal 4G, Mobile Card Terminal Plus, Mobile Card Terminal.
Viva Wallet POS app for Android	Mini Card Reader, Pocket Card Terminal connected via Bluetooth or USB to the Viva Wallet POS app for Android.