flutter_smart_cache_manager 0.0.6

A lightweight Flutter caching library with TTL, cache policies, offline fallback, disk persistence, and background refresh for optimized API performance.

example/lib/main.dart

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

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(home: CacheDemo());
  }
}

/// Shows both storage backends side by side so the difference is visible:
///
/// * `MemoryStorage` — RAM only. "API calls" resets to 0 every time the app
///   is fully closed and reopened, because the cache is gone with it.
/// * `PersistentStorage` — written to disk. Fully close the app and reopen
///   it: this card still shows the same cached text, and "API calls" stays
///   at 1 (won't refetch until the 5-minute TTL expires).
///
/// Tap "Fetch" on either card to trigger a (simulated) network call.
class CacheDemo extends StatelessWidget {
  const CacheDemo({super.key});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Smart Cache Manager Demo')),
      body: const Padding(
        padding: EdgeInsets.all(16),
        child: Column(
          children: [
            _CacheCard(
              title: 'MemoryStorage',
              subtitle: 'RAM only — cleared on every app restart',
              cacheKey: 'memory_user',
              storageBuilder: _memoryStorage,
            ),
            SizedBox(height: 16),
            _CacheCard(
              title: 'PersistentStorage',
              subtitle: 'Written to disk — survives app restarts',
              cacheKey: 'persistent_user',
              storageBuilder: _persistentStorage,
            ),
          ],
        ),
      ),
    );
  }
}

Future<CacheStorage> _memoryStorage() async => MemoryStorage();

Future<CacheStorage> _persistentStorage() => PersistentStorage.create();

class _CacheCard extends StatefulWidget {
  const _CacheCard({
    required this.title,
    required this.subtitle,
    required this.cacheKey,
    required this.storageBuilder,
  });

  final String title;
  final String subtitle;
  final String cacheKey;
  final Future<CacheStorage> Function() storageBuilder;

  @override
  State<_CacheCard> createState() => _CacheCardState();
}

class _CacheCardState extends State<_CacheCard> {
  CacheManager? _cache;
  String _text = 'Not loaded yet';
  int _apiCalls = 0;
  bool _loading = false;

  @override
  void initState() {
    super.initState();
    _load();
  }

  Future<void> _load() async {
    setState(() => _loading = true);

    // Built once per card and reused — a fresh CacheManager still finds
    // whatever PersistentStorage already has on disk from a previous run.
    _cache ??= CacheManager(await widget.storageBuilder());

    final result = await _cache!.get<String>(
      key: widget.cacheKey,
      ttl: const Duration(minutes: 5),
      fetcher: () async {
        await Future.delayed(const Duration(seconds: 1));
        _apiCalls++;
        print('[${widget.title}] API CALLED (call #$_apiCalls)');
        return 'Hello Vishal @ ${DateTime.now().toIso8601String()}';
      },
    );

    if (!mounted) return;
    setState(() {
      _text = result;
      _loading = false;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(12),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(
              widget.title,
              style: Theme.of(context).textTheme.titleMedium,
            ),
            Text(widget.subtitle, style: Theme.of(context).textTheme.bodySmall),
            const SizedBox(height: 8),
            Text(_text),
            const SizedBox(height: 4),
            Text('API calls this session: $_apiCalls'),
            const SizedBox(height: 8),
            ElevatedButton(
              onPressed: _loading ? null : _load,
              child: Text(_loading ? 'Loading...' : 'Fetch'),
            ),
          ],
        ),
      ),
    );
  }
}