Talk given at the Droidcon DE 2013 in Berlin about integrating payments into Android applications without making the user entering too much data.

2. Developer

3. Painless Payments for Droids
Tim Messerschmidt

4. Painless Payments for Droids
Tim Messerschmidt

5. Log In with PayPal
The Artist
formerly known
as access

6. Log In with PayPal
Authentication

7. Log In with PayPal
Authorization

8. Log In with PayPal
OAuth 2.0 &
OpenID Connect

9. Log In with PayPal
Client Server
1. Open Authorization 2. Provide a login page
Endpoint URL 3. Return the Authorization
4. Check callbacks for Token after a successful
Authorization Token login
5. Request a valid Access 6. Check Authorization Token
Token & return the Access Token
7. Retrieve user’s resources if it’s valid

10. Log In with PayPal
NAME Date of Birth
Creation Date
EMAIL Language
Gender Locale
Time Zone
Phone Number Address
Verified

11. Painless Payments for Droids
Tim Messerschmidt

12. Painless Payments for Droids
Tim Messerschmidt

14. Painless Payments for Droids
Tim Messerschmidt

19. Simple Payment
10 €
Sender Receiver

20. Parallel Payment
20 €
10 €
Sender

21. Chained Payment
20 €
100 €
30 €
10 €
1 transaction

23. Mobile Payments Library
Download
the SDK

24. Mobile Payments Library
API Credentials
At x.com

25. Mobile Payments Library
Sandbox APP ID:
APP-80W284485P519543T

26. Mobile Payments Library
Add The .JAR To
Your Project

27. Mobile Payments Library
Modify the
Manifest

28. Mobile Payments Library
Adding the PayPal Activity:
<activity
android:name="com.paypal.android.MEP.PayPalActivity"
android:configChanges="keyboardHidden|orientation" />
Best to be used with a translucent Theme
android:theme="@android:style/Theme.Translucent.NoTitleBar"

29. Mobile Payments Library
DECLARING THE NEEDED PERMISSIONS:
Internet
<uses-permission
android:name="android.permission.INTERNET" />
READ Phone state
<uses-permission
android:name="android.permission.READ_PHONE_STATE" />
Access Wifi State
<uses-permission
android:name="android.permission.ACCESS_WIFI_STATE" />

30. Mobile Payments Library
Initialize The
Library

31. Mobile Payments Library
new Thread() {
public void run() {
instance = PayPal.getInstance();
if (instance == null) {
instance = PayPal.initWithAppID(
context,
ID, // YOUR APP'S ID
PayPal.ENV_SANDBOX
);
}
}
}.start();

32. Mobile Payments Library
Create the
PAYMENT

33. Mobile Payments Library
Simple Payment:
PayPalPayment payment = new PayPalPayment();
payment.setRecipient("foo@bar.com");
payment.setCurrencyType("USD");
payment.setPaymentType(PayPal.PAYMENT_TYPE_GOODS);
payment.setSubtotal(new BigDecimal(”29.99"));
PayPalInvoiceItem item = new PayPalInvoiceItem();
item.setName("Hipster T-Shirt");
item.setQuantity(1);
item.setTotalPrice(new BigDecimal(”29.99"));
PayPalInvoiceData data = new PayPalInvoiceData();
data.add(item);
payment.setInvoiceData(data);

34. Mobile Payments Library
Parallel Payment:
PayPalAdvancedPayment payment = new PayPalAdvancedPayment();
payment.setCurrencyType("USD");
PayPalReceiverDetails firstReceiver =
new PayPalReceiverDetails();
firstReceiver.setRecipient("first@bar.com");
firstReceiver.setSubtotal(new BigDecimal("10.00"));
PayPalReceiverDetails secondReceiver =
new PayPalReceiverDetails();
secondReceiver.setRecipient("second@bar.com");
secondReceiver.setSubtotal(new BigDecimal("20.00"));
payment.getReceivers().add(firstReceiver);
payment.getReceivers().add(secondReceiver);

35. Mobile Payments Library
Execute The
Payment

36. Mobile Payments Library
GET THE INTENT:
Intent payIntent =
instance.checkout(invoice, context);
startActivityForResult(payIntent, REQUEST);
Can be used with a Delegate instead
Intent payIntent =
instance.checkout(
invoice, context, delegate
);
startActivity(payIntent);

37. Mobile Payments Library
Receive the result:
protected void onActivityResult(
int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST) {
switch (resultCode) {
case Activity.RESULT_OK:
showText("Success");
break;
case Activity.RESULT_CANCELED:
showText("Canceled");
break;
case PayPalActivity.RESULT_FAILURE:
showText("Failure");
break;
}
}
}

38. Mobile Payments Library
Advantage:
Intent-based

39. Mobile Payments Library
Use IPN to update
your stock

40. Mobile Payments Library
Verify Payments:
payment.setIpnUrl("http://example.com/callback.php");
POST
PayPal Server
Server PayPal

41. Mobile Payments Library
CODE