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[英]The method 'RaisedButton' isn't defined for the type '_SignUpState'
[英]Error: The method 'raisedButton' isn't defined for the class '_PomodoroState'
我目前正在 android studio 中做一個 flutter 教程,我遇到了這個問題,我試圖創建一個類,試圖將它變成一個變量,但沒有運氣,我還命名了一個文件“raised_button.dart”並使用了 stful 小部件看看它是否有效但它不起作用這是我的代碼:
import 'package:flutter/material.dart';
import 'package:percent_indicator/circular_percent_indicator.dart';
import 'dart:async';
void main() => runApp(MaterialApp(
debugShowCheckedModeBanner: false,
home: Pomodoro(),
));
class Pomodoro extends StatefulWidget {
const Pomodoro({Key? key}) : super(key: key);
@override
State<Pomodoro> createState() => _PomodoroState();
}
class _PomodoroState extends State<Pomodoro> {
double percent = 0;
static int TimeInMinut = 240;
int TimeInSec = TimeInMinut * 60;
late Timer timer;
_StartTimer(){
TimeInMinut = 240;
int Time = TimeInMinut *60;
double SecPercent = (Time/100);
timer = Timer.periodic(Duration(seconds:1), (timer) {
setState((){
if(Time > 0){
Time--;
if(Time % 60 ==0){
TimeInMinut --;
}if(Time % SecPercent == 0){
if(percent <1){
percent += 0.01;
}else{
percent = 1;
}
}
}else{
percent = 0;
TimeInMinut = 240;
timer.cancel();
}
});
});
}
@override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Container(
decoration: BoxDecoration(
gradient: LinearGradient(
colors: [Colors.orangeAccent, Colors.redAccent],
begin: FractionalOffset(0.5,1)
)
),
width: double.infinity,
child: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
Padding(
padding: EdgeInsets.only(top: 25.0),
child: Text(
"Pomodoro Clock",
style: TextStyle(
color: Colors.white,
fontSize: 40.0
),
),
),
Expanded(
child: CircularPercentIndicator(
percent: percent,
animation: true,
animateFromLastPercent: true,
radius: 150.0,
lineWidth: 20.0,
progressColor: Colors.white,
center: Text(
"$TimeInMinut",
style: TextStyle(
color: Colors.white,
fontSize: 80.0
),
),
),
),
SizedBox(height: 10.0,),
Expanded(
child: Container(
width: double.infinity,
decoration: BoxDecoration(
color: Colors.white,
borderRadius: BorderRadius.only(topRight: Radius.circular(30.0),topLeft: Radius.circular(30.0))
),
child: Padding(
padding: EdgeInsets.only(top: 30.0, left: 20.0, right: 20.0),
child: Column(
children: <Widget>[
Expanded(
child: Row(
children: <Widget>[
Expanded(
child: Column(
children: <Widget>[
Text(
"Focus Time",
style: TextStyle(
fontSize: 20.0,
),
),
SizedBox(height: 10.0,),
Text(
"240",
style: TextStyle(
fontSize: 50.0
),
),
]
),
),
Expanded(
child: Column(
children: <Widget>[
Text(
"Pause Time",
style: TextStyle(
fontSize: 20.0,
),
),
SizedBox(height: 10.0,),
Text(
"20",
style: TextStyle(
fontSize: 50.0
),
),
]
),
)
],
)
),
Padding(
padding: EdgeInsets.symmetric(vertical: 28.0),
child: raisedButton(
onPressed: _StartTimer,
color: Colors.redAccent,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(100.0),
),
child: Padding(
padding: EdgeInsets.all(20.0),
child: Text("Start focusing",
style: TextStyle(
color: Colors.white,
fontSize: 22.0
),
),
)
),
)
],
)
),
),
),
],
),
),
),
);
}
}
這是終端上顯示的內容
lib/main.dart:151:38: Error: The method 'raisedButton' isn't defined for the class '_PomodoroState'.
- '_PomodoroState' is from 'package:pomodoris/main.dart' ('lib/main.dart').
Try correcting the name to the name of an existing method, or defining a method named 'raisedButton'.
child: raisedButton(
在那種特殊情況下我應該怎么做? 先感謝您。
我認為人們應該看到你的 raiseButton class 來獲得答案。 如果它是一個單獨的 class 這里應該是一個導入,但它不是。 並且 class 名稱應以大寫字母開頭
大寫 R。 它是RaisedButton
,而不是raisedButton
。
但是, RaisedButton
已被貶低。 代替
raisedButton(
onPressed: _StartTimer,
color: Colors.redAccent,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(100.0),
),
child: Padding(
你想使用ElevatedButton
。 您還需要將樣式移動到新的樣式屬性,將顏色等傳遞給 ElevatedButton.styleFrom() 構造函數。
ElevatedButton(
style: ElevatedButton.styleFrom(
primary: Colors.red,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(100.0),
),
),
onPressed: _StartTimer,
child: Padding(
但是...根據 Flutter 遵循的材料指南,此外觀也被貶低。 在此處查看如何使按鈕看起來既美觀又現代: https://material.io/components/buttons所有名稱也是 Flutter 中小部件的名稱。 如果您卡在那里,請隨時再次詢問!
**RaisedButton 在最新的 flutter 版本上已棄用。 您可以用 ElevatedButton 替換 RaisedButton **
ElevatedButton(
child: Text('ElevatedButton'))
Flutter 新版本不再使用 RaisedButton
相反,您可以使用高架按鈕
ElevatedButton(
onPressed: () {
print('login clicked');
},
child: Text(
'Login',
style: TextStyle(fontSize: 18.0, fontFamily: "Brand Bold"),
))
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