bring_app_to_foreground 0.1.1

Bring a Flutter app to the foreground from the background on Android (incoming VoIP/dispatch calls, alarms) via the Display-over-other-apps permission.

example/lib/main.dart

import 'dart:async';

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

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

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'bring_app_to_foreground',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.indigo),
        useMaterial3: true,
      ),
      home: const HomePage(),
    );
  }
}

class HomePage extends StatefulWidget {
  const HomePage({super.key});

  @override
  State<HomePage> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> with WidgetsBindingObserver {
  bool _hasPermission = false;
  int _countdown = 0;
  Timer? _timer;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
    _refreshPermission();
  }

  @override
  void dispose() {
    _timer?.cancel();
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    // Re-check the permission when returning from the system settings page
    // (or from being backgrounded), since the user may have just granted it.
    if (state == AppLifecycleState.resumed) {
      _refreshPermission();
    }
  }

  Future<void> _refreshPermission() async {
    final bool granted = await BringAppToForeground.hasPermission();
    if (!mounted) return;
    setState(() => _hasPermission = granted);
  }

  Future<void> _requestPermission() async {
    await BringAppToForeground.requestPermission();
    // The real status arrives on resume via didChangeAppLifecycleState; refresh
    // now as well in case the page returned synchronously.
    await _refreshPermission();
  }

  void _startCountdown() {
    _timer?.cancel();
    setState(() => _countdown = 5);
    _timer = Timer.periodic(const Duration(seconds: 1), (Timer timer) async {
      if (!mounted) return;
      if (_countdown <= 1) {
        timer.cancel();
        setState(() => _countdown = 0);
        await BringAppToForeground.bringToFront();
      } else {
        setState(() => _countdown -= 1);
      }
    });
  }

  @override
  Widget build(BuildContext context) {
    final bool counting = _countdown > 0;
    return Scaffold(
      appBar: AppBar(title: const Text('bring_app_to_foreground')),
      body: Padding(
        padding: const EdgeInsets.all(24),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: <Widget>[
                Icon(
                  _hasPermission ? Icons.check_circle : Icons.cancel,
                  color: _hasPermission ? Colors.green : Colors.red,
                ),
                const SizedBox(width: 8),
                Text(
                  _hasPermission
                      ? '"Display over other apps" granted'
                      : 'Permission not granted',
                  style: Theme.of(context).textTheme.titleMedium,
                ),
              ],
            ),
            const SizedBox(height: 32),
            FilledButton.tonal(
              onPressed: _refreshPermission,
              child: const Text('Check permission'),
            ),
            const SizedBox(height: 12),
            FilledButton(
              onPressed: _hasPermission ? null : _requestPermission,
              child: const Text('Grant permission'),
            ),
            const SizedBox(height: 12),
            FilledButton(
              onPressed: counting ? null : _startCountdown,
              child: Text(
                counting
                    ? 'Press Home now... $_countdown'
                    : 'Bring to front in 5s',
              ),
            ),
            const SizedBox(height: 24),
            Text(
              'Tap "Bring to front in 5s", press the Home button, and the app '
              'should pop back to the foreground after the countdown.',
              textAlign: TextAlign.center,
              style: Theme.of(context).textTheme.bodySmall,
            ),
          ],
        ),
      ),
    );
  }
}