usesmileid_njia 0.0.1-SNAPSHOT.13

Smile ID's flow navigation engine for Flutter: a thin bridge to the native njia cores, which own the back stack. Only navigation crosses the bridge.

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:usesmileid_njia/usesmileid_njia.dart';

/// usesmileid_njia's example: a two-step flow on the native engine, with next and back.
void main() => runApp(const MaterialApp(home: ExampleFlow()));

enum Kind { intro, capture }

enum Fact { seen }

final codec = NjiaCodec(kinds: NjiaWire.ofEnum(Kind.values), facts: NjiaWire.ofEnum(Fact.values));

const graph = NjiaGraph<Kind, Fact>(
  nodes: [
    NjiaStep(id: 'intro', kind: Kind.intro),
    NjiaStep(id: 'capture', kind: Kind.capture),
  ],
);

/// The flow, drawn by NjiaHost, each step with buttons that move it from its own entry.
class ExampleFlow extends StatefulWidget {
  /// The example's only screen.
  const ExampleFlow({super.key});

  @override
  State<ExampleFlow> createState() => _ExampleFlowState();
}

class _ExampleFlowState extends State<ExampleFlow> {
  NjiaEngine<Kind, Fact>? _engine;

  @override
  void initState() {
    super.initState();
    NjiaEngine.start(codec, graph).then((engine) {
      // Gone before the engine started: release it rather than leak it in the bridge.
      if (!mounted) {
        engine.dispose();
        return;
      }
      setState(() => _engine = engine);
    });
  }

  @override
  void dispose() {
    _engine?.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final engine = _engine;
    return Scaffold(
      appBar: AppBar(title: const Text('njia')),
      body: engine == null
          ? const Center(child: CircularProgressIndicator())
          : NjiaHost(
              engine: engine,
              builder: (context, scope) => Column(
                children: [
                  Text('${scope.step.kind.name} · visit ${scope.entry.visit}'),
                  Row(
                    children: [
                      TextButton(onPressed: scope.navigator.next, child: const Text('next')),
                      TextButton(onPressed: scope.navigator.back, child: const Text('back')),
                    ],
                  ),
                ],
              ),
            ),
    );
  }
}