Detect when user is not interacting the app in Flutter

Question

I want to show some Screensaver type of screen when the user is not interacting the app for 5 minutes. So is anyone know how to achieve this kind of functionality in flutter.

import 'dart:async';

import 'package:flutter/material.dart';

const timeout = const Duration(seconds: 10);
const ms = const Duration(milliseconds: 1);
Timer timer;

void main() =>
    runApp(MyApp());


class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    var home = MyHomePage(title: 'Flutter Demo Home Page');
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: home,
    );
  }


}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);
  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _goToSecondScreen() {
    Navigator.pushReplacement(
      context,
      MaterialPageRoute(builder: (context) => SecondPage()),
    );
  }

  @override
  Widget build(BuildContext context) {
    return GestureDetector(child: Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Container(),
      floatingActionButton: FloatingActionButton(
        onPressed: _goToSecondScreen,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    ), behavior:
    HitTestBehavior.translucent, onTapDown: (tapdown) {
      print("down");
      if (timer != null) {
        timer.cancel();
      }
      timer = startTimeout();
    },);
  }

  startTimeout([int milliseconds]) {
    var duration = milliseconds == null ? timeout : ms * milliseconds;
    return new Timer(duration, handleTimeout);
  }

  void handleTimeout() {
    Navigator.push(
      context,
      MaterialPageRoute(builder: (context) => ScreenSaver()),
    );
  }

}

class SecondPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new Container();
  }
}
class ScreenSaver extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return new GestureDetector(child:Container(color: Colors.yellow,),
      onTap: (){
        Navigator.pop(context);
      },
    );
  }
}

This is the sample code which I am trying to achieve the functionality. When the screen in active in Second screen its not working and the GestureDetector stops listening.

Answer 1

You can wrap your whole app in a GestureDetector with behavior: HitTestBehavior.translucent to receive touch events while allowing widgets in your app also receiving these touch events.

You might also want to listen to keyboard events External keyboard in flutter support