Atomic Transact for Flutter

A Flutter plugin that wraps the native Atomic Transact SDKs

Installation

Add atomic_transact_flutter as a dependency in your pubspec.yaml file:

dependencies:
  ...
  atomic_transact_flutter: <version>

iOS Requirements

• Xcode 12.0 or greater
• iOS 14.0 or greater

Android Requirements

Set the minSdkVersion in android/app/build.gradle:

android {
    defaultConfig {
        minSdkVersion 21 // or greater
    }
}

Presentation style

Each platform has its own presentation style, and each one ignores the other's. iOS presents Transact as a form sheet by default, and Android presents it full screen. Pass presentationStyleIOS or presentationStyleAndroid to change that:

await Atomic.transact(
  config: config,
  presentationStyleIOS: AtomicPresentationStyleIOS.fullScreen,
  presentationStyleAndroid: AtomicPresentationStyleAndroid.formSheet,
);

On Android, the form sheet is a bottom sheet over your dimmed app on phones, and a centered card on screens of at least 600×480dp. It's modal, so users close it with Transact's close button or the back button, not by swiping it down or tapping outside it.

Responding to data requests

Transact emits a data request when it needs information that only your app can supply, such as card or identity details for a deferred payment method. Return an AtomicTransactDataResponse from onDataRequest and it is sent back to Transact. The handler may be asynchronous, so you can prompt the user or call your backend before responding.

await Atomic.transact(
  config: config,
  onDataRequest: (request) async {
    // request.fields lists what Transact is asking for, e.g. ['card']
    final card = await promptForCard();

    return AtomicTransactDataResponse(
      card: AtomicTransactCardData(
        number: card.number,
        expiry: card.expiry, // MM/YY
        cvv: card.cvv,
        cardType: AtomicTransactCardType.debit,
      ),
      identity: const AtomicTransactIdentity(
        firstName: 'Ada',
        lastName: 'Lovelace',
        postalCode: '84043',
      ),
    );
  },
);

Returning null sends nothing back, and Transact keeps waiting for data.

Running more than one Transact flow

Every Atomic.transact call gets its own callbacks, so launching Transact again never replaces the callbacks of a flow that's still running. A task can keep sending onTaskStatusUpdate after onCompletion, while its work finishes in the background. onCleanup is the last callback a flow sends. After it, the flow sends nothing more.

final task = await Atomic.transact(
  config: config,
  onTaskStatusUpdate: (update) => print('${update.taskId}: ${update.status}'),
  onCompletion: (type, response, error) => print('UI closed: ${type.name}'),
  onCleanup: () => print('done'),
);

// Stop receiving this flow's callbacks without closing Transact.
task.remove();

Atomic.close() closes every flow that hasn't finished or closed yet, including hidden and paused ones. Those flows get onCleanup but not onCompletion, so reset any "Transact is open" state there too. Atomic.hide() hides every Transact on screen, and those flows keep running.

Upgrading

• Atomic.transact no longer ignores calls while Transact is open. Every call launches Transact, so disable your launch button until onCompletion if you only want one flow at a time.
• Atomic.transact now returns a Future<AtomicTransactTask> instead of Future<void>. It throws a PlatformException if Transact can't be presented, so await it or catch the error.

More info at https://docs.atomicfi.com.