Login screen, registration screen, etc. all screens are displaying but welcome screen is not showing:
Errors:
1-setState() or markNeedsBuild() called during build.
2-Failed assertion: line 4165 pos 12: '!_debugLocked': is not true.
3-'package:flutter/src/widgets/navigator.dart': Failed assertion: line 4165 pos 12: '!_debugLocked': is not true.
import 'package:flutter/material.dart';
import 'login_screen.dart';
import 'registration_screen.dart';
import 'package:animated_text_kit/animated_text_kit.dart';
import 'package:flash_chat/components/rounded_button.dart';
class WelcomeScreen extends StatefulWidget {
static const String id = 'welcome_screen';
@override
_WelcomeScreenState createState() => _WelcomeScreenState();
}
class _WelcomeScreenState extends State<WelcomeScreen> with SingleTickerProviderStateMixin{
late AnimationController controller;
late Animation animation;
@override
void initState() {
super.initState();
controller = AnimationController(
duration: Duration(seconds: 1),
vsync: this,
);
animation = ColorTween(begin: Colors.blueGrey, end: Colors.white).animate(controller);
controller.forward();
controller.addListener(() {
setState(() {});
});
}
@override
void dispose() {
controller.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: animation.value,
body: Padding(
padding: EdgeInsets.symmetric(horizontal: 24.0),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Row(
children: <Widget>[
Hero(
tag: 'logo',
child: Container(
child: Image.asset('images/logo.png'),
height: 60.0,
),
),
TypewriterAnimatedTextKit(
text: ['Chat'],
textStyle: TextStyle(
fontSize: 45.0,
fontWeight: FontWeight.w900,
color: Colors.black54,
),
),
],
),
SizedBox(
height: 48.0,
),
RoundedButton(
title: 'Log In',
colour: Colors.lightBlueAccent,
onPressed: () {
Navigator.pushNamed(context, LoginScreen.id);
},
),
RoundedButton(
title: 'Register',
colour: Colors.blueAccent,
onPressed: () {
Navigator.pushNamed(context, RegistrationScreen.id);
},
),
],
),
),
);
}
}
CodePudding user response:
Try WidgetsBinding.instance.addPostFrameCallback.
WidgetsBinding.instance.addPostFrameCallback((timeStamp) {
setState(() {
});
}
CodePudding user response:
copy and paste the code
animation = ColorTween(begin: Colors.blueGrey, end:
Colors.white).animate(controller);
controller.forward();
controller.addListener(() {
WidgetsBinding.instance.addPostFrameCallback((timeStamp) {
setState(() { });
}
});