Вы можете скопировать и вставить полный код ниже
Вы можете обернуть Positioned
с помощью Visibility
и через некоторое время установить visible
на false
фрагмент кода
_hideBar() {
Timer(Duration(seconds: 5), () {
setState(() {
_visible = false;
});
});
}
@override
void initState() {
super.initState();
WidgetsBinding.instance.addPostFrameCallback((_) {
_hideBar();
});
}
...
Visibility(
visible: _visible,
child: Positioned(
height: 32.0,
рабочая демонстрация
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полный код
import 'package:flutter/material.dart';
import 'package:flutter_offline/flutter_offline.dart';
import 'dart:async';
class DemoPage extends StatefulWidget {
@override
_DemoPageState createState() => _DemoPageState();
}
class _DemoPageState extends State<DemoPage> {
bool _visible = true;
_hideBar() {
Timer(Duration(seconds: 5), () {
setState(() {
_visible = false;
});
});
}
@override
void initState() {
super.initState();
WidgetsBinding.instance.addPostFrameCallback((_) {
_hideBar();
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Offline Demo"),
),
body: OfflineBuilder(
connectivityBuilder: (
BuildContext context,
ConnectivityResult connectivity,
Widget child,
) {
final bool connected = connectivity != ConnectivityResult.none;
return Stack(
fit: StackFit.expand,
children: [
child,
Visibility(
visible: _visible,
child: Positioned(
height: 32.0,
left: 0.0,
right: 0.0,
child: AnimatedContainer(
duration: const Duration(milliseconds: 350),
color: connected ? Color(0xFF00EE44) : Color(0xFFEE4400),
child: AnimatedSwitcher(
duration: const Duration(milliseconds: 350),
child: connected
? Text('ONLINE')
: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text('OFFLINE'),
SizedBox(width: 8.0),
SizedBox(
width: 12.0,
height: 12.0,
child: CircularProgressIndicator(
strokeWidth: 2.0,
valueColor: AlwaysStoppedAnimation<Color>(
Colors.white),
),
),
],
),
),
),
),
),
],
);
},
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'There are no bottons to push :)',
),
Text(
'Just turn off your internet.',
),
],
),
),
);
}
}
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: DemoPage(),
);
}
}