Issue
So this is the main code where I fetch the data from json and update my UI. I have placed" //Area of Interest " comments where the code related to the problem lies.
class MainScreen extends StatefulWidget {
final curLocdata;
MainScreen({this.curLocdata});
@override
_MainScreenState createState() => _MainScreenState();
}
class _MainScreenState extends State<MainScreen> {
Weather weather = Weather();
var cityName;
int temp;
int temp_min;
int temp_max;
Icon weatherIcon;
//Area of Interest 1
RotateAnimatedTextKit textSum;//created a widget of RotateAnimatedTextKit library.
String st;
//Area of Interest 2
@override
void initState() {
// TODO: implement initState
super.initState();
updateUI(widget.curLocdata);//calling update function to rebuild my UI state with new data
}
void updateUI(data) {
setState(() {
if (data == null) {
temp = 0;
cityName = 'Error';
weatherIcon = Icon(Icons.error);
return;
}
cityName = data['name'];
temp = data['main']['temp'].toInt();
temp_min = data['main']['temp_min'].toInt();
temp_max = data['main']['temp_max'].toInt();
var condition = data['weather'][0]['id'];
weatherIcon = weather.getIcon(condition);
textSum = weather.getMessage(temp);//Area of Interest 3
st = weather.subtext(condition);
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Container(
child: SafeArea(
child: Column(
children: <Widget>[
Container(
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
FlatButton(
onPressed: () async {
updateUI(await Network().getData());
},
child: Icon(
FontAwesomeIcons.locationArrow,
),
),
SizedBox(
width: 180.0,
child: TextLiquidFill(
waveDuration: Duration(seconds: 3),
loadDuration: Duration(seconds: 10),
text: 'OpenWeather',
waveColor: Colors.red,
boxBackgroundColor: Color(0xFF1B1B1D),
textStyle: TextStyle(
fontSize: 30.0,
fontWeight: FontWeight.bold,
fontFamily: 'Source Sans Pro',
),
boxHeight: 50.0,
),
),
FlatButton(
onPressed: () async {
String SName = await Navigator.push(context,
MaterialPageRoute(builder: (context) {
return Search();
}));
if (SName != null) {
updateUI(await Network().getDataName(
SName));
}
},
child: Icon(
Icons.add,
color: Colors.white,
size: 40,
),
),
],
),
),
Padding(
padding: EdgeInsets.fromLTRB(50, 50, 50, 0),
child: Row(
children: <Widget>[
SizedBox(
// margin: EdgeInsets.fromLTRB(0, 50, 260, 0),
child: TypewriterAnimatedTextKit(
totalRepeatCount: 200,
isRepeatingAnimation: true,
speed: Duration(milliseconds: 700),
text: [cityName,],
textAlign: TextAlign.left,
textStyle: TextStyle(
fontSize: 20,
fontFamily: 'Source Sans Pro',
),
),
),
],
)),
Expanded(
flex: 9,
child: Container(
margin: EdgeInsets.fromLTRB(50, 30, 50, 80),
child: Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
//mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
Expanded(
flex: 2,
child: Padding(
padding: EdgeInsets.only(left: 20),
child: Text(
'$temp°',
style: TextStyle(
fontSize: 80,
fontWeight: FontWeight.bold,
fontFamily: 'Source Sans Pro',
),
),
),
),
Expanded(
flex: 2,
child: Padding(
padding: EdgeInsets.only(left: 20),
child: Text(
st,
style: TextStyle(
fontSize: 30,
fontFamily: 'Source Sans Pro',
color: Colors.grey[500]),
),
),
),
Padding(
padding: EdgeInsets.fromLTRB(20, 0, 0, 50),
child: Container(
child: textSum,//Used this textSum to show my animated text. problem
Area of Interest 4
),
),
Expanded(
child: SizedBox(
//width: double.infinity,
//height: 100,
child: Divider(
color: Colors.red,
),
),
),
Row(
children: <Widget>[
Expanded(
child: Padding(
padding: EdgeInsets.fromLTRB(20, 0, 0, 38),
child: Text(
'$temp_min° - $temp_max°',
style: TextStyle(
fontSize: 20,
color: Colors.grey[500],
fontFamily: 'Source Sans Pro',
),
),
),
),
Expanded(
child: Padding(
padding: EdgeInsets.fromLTRB(20, 0, 0, 20),
//padding: const EdgeInsets.all(8.0),
child: AvatarGlow(
endRadius: 30.0, //required
child: Material(
//required
elevation: 0.0,
shape: CircleBorder(),
child: CircleAvatar(
//backgroundColor: Colors.grey[100],
child: weatherIcon
// radius: 40.0,
//shape: BoxShape.circle
),
),
),
),
)
],
)`enter code here`
],
),
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(10),
color: Color(0xFF0C0C0C),
),
),
),
Now the weather.dart file from where I am returning RotateAnimatedTextKit widget depending upon the condition
class Weather{
//This return RotateAnimatedTextKit which is then held by textSum and is put as a child inside a container in MainScreen
RotateAnimatedTextKit getMessage(int temp) {
if (temp > 25) {
return RotateAnimatedTextKit(
isRepeatingAnimation: true,
totalRepeatCount: 200,
transitionHeight: 40,
text: ['It\'s 🍦','time and','drink plenty','of water'],
textStyle: TextStyle(fontSize: 30.0, fontFamily: "Source Sans Pro", color: Colors.red),
textAlign: TextAlign.start,
alignment: AlignmentDirectional.topStart // or Alignment.topLeft
);
} else if (temp > 20) {
return RotateAnimatedTextKit(
isRepeatingAnimation: true,
totalRepeatCount: 200,
transitionHeight: 50,
text: ['Time for','shorts','👕','but keep','some warm','clothes handy'],
textStyle: TextStyle(fontSize: 30.0, fontFamily: "Source Sans Pro", color: Colors.red),
textAlign: TextAlign.start,
alignment: AlignmentDirectional.bottomStart// or Alignment.topLeft
);
} else if (temp < 10) {
return RotateAnimatedTextKit(
isRepeatingAnimation: true,
totalRepeatCount: 200,
transitionHeight: 50,
text: ['You\'ll need','a 🧣','and','a 🧤','and a hot', 'soup and turkey'],
textStyle: TextStyle(fontSize: 30.0, fontFamily: "Source Sans Pro", color: Colors.red),
textAlign: TextAlign.start,
alignment: AlignmentDirectional.bottomStart // or Alignment.topLeft
);
} else {
return RotateAnimatedTextKit(
isRepeatingAnimation: true,
transitionHeight: 50,
totalRepeatCount: 200,
text: ['Bring a','🧥','just in case','and also avoid', 'cold breeze','and cold drinks'],
textStyle: TextStyle(fontSize: 30.0, fontFamily: "Source Sans Pro", color: Colors.red),
textAlign: TextAlign.start,
alignment: AlignmentDirectional.bottomStart // or Alignment.topLeft
);
}
}
The thing is that the UI doesn't get updated even when the conditions are different. So any Solutions to why the widget tree is not updating? But it runs only the default text. Also, the cityName which is under the TextLiquidFill doesn't get updated.
Solution
Short answer: Use Keys
Example:
import 'package:animated_text_kit/animated_text_kit.dart';
import 'package:flutter/material.dart';
class MyAnimatedText extends StatefulWidget {
const MyAnimatedText({Key? key}) : super(key: key);
@override
State<MyAnimatedText> createState() => _MyAnimatedTextState();
}
class _MyAnimatedTextState extends State<MyAnimatedText> {
bool isDarkMode = true;
@override
Widget build(BuildContext context) {
return Container(
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(30),
color: isDarkMode ? Colors.grey[850] : Colors.amber[300]),
child: Column(
children: [
Container(
alignment: Alignment.topRight,
child: IconButton(
onPressed: () {
setState(() {
isDarkMode = !isDarkMode;
});
},
icon: Icon(isDarkMode ? Icons.light_mode : Icons.dark_mode))),
Padding(
padding: const EdgeInsets.all(15.0),
child: AnimatedTextKit(
key: ValueKey<bool>(isDarkMode),
animatedTexts: [
TypewriterAnimatedText(
isDarkMode ? 'Have a nice evening ;)' : 'Have a nice day :)',
cursor: isDarkMode ?'>':'<',
textStyle: TextStyle(
fontSize: 38,
color: isDarkMode ? Colors.amber[300] : Colors.grey[850]),
speed: const Duration(milliseconds: 100),
),
],
),
),
],
),
);
}
}
Result:
Background Information
I faced the same problem, when I tried to implement a dark / light change. The background color was defined in an other widget and changed, the font color was defined in the TypewriterAnimatedText Widget and only changed in the second loop. The color was not changing in the runnig animation.
Solution: use Keys The Animation does not change beacause Flutter tries to keep the state of an StatefulWidget and the AnimatedTextKit is a Stateful Widget. To force a rebuild you can use a Key.
a nice article can be found here: How to force a Widget to redraw in Flutter?
Answered By - SeriForte
Answer Checked By - Cary Denson (JavaFixing Admin)