InAppPayments

How to integrate in-app payments in your Android app.

This document describes API version 1.0. API version 2.0 has just been released into beta, which adds the ability to use BIP70 formatted payment requests and get a payment message as a result. I will extend this document shortly.

Introduction

You might want to send Bitcoins from your app. A common example is a donation button.

Check out the code from the repository. There are two subprojects for in-app payments:

• integration-android: A tiny library for integrating Bitcoin payments into your own Android app (e.g. donations, in-app purchases).
• sample-integration-android: A minimal example app to demonstrate integration of Bitcoin payments into your Android app.

Have a look at the Javadoc for the class BitcoinIntegration.

Sending the request

class de.schildbach.wallet.integration.android.BitcoinIntegration

/*
 * Request specific amount of Bitcoins from user,
 * without feedback from the app.
 */
static void request(Context context, String address, long amount);

/*
 * Request specific amount of Bitcoins from user,
 * with feedback from the app.
 */    
static void requestForResult(Activity activity, int requestCode,
                             String address, long amount);

Methods for requests without amount are also available!

The above methods send an intent to any Bitcoin app which listens to it.

action = android.intent.action.VIEW
data = bitcoin:1PZmMahjbfsTy6DsaRyfStzoWTPppWwDnZ?amount=0.1

The URL is formatted to BIP21 standard.

Retrieving the result

Some apps return a result through onActivityResult() after the user has gone through the sending process. In this case you can read some useful extras:

resultCode = OK|CANCELED
extras[transaction_hash] = c8a9e036ecbbe75c...

You can use this convenience method to fetch the hash:

class de.schildbach.wallet.integration.android.BitcoinIntegration

/**
 * Get transaction hash from result intent.
 */
static String transactionHashFromResult(final Intent result);

This is an example of code for using the result:

protected void onActivityResult(int requestCode, int resultCode, Intent result)
{
    if (requestCode == REQUEST_CODE && resultCode == Activity.RESULT_OK)
    {
        String txHash = BitcoinIntegration.transactionHashFromResult(result);
        if (txHash != null)
        {
            // thank you!
            // (but: no guarantees)
        }
    }
    else if (resultCode == Activity.RESULT_CANCELED)
    {
        // cancelled
    }
    else
    {
        // something went wrong
    }

}