返回字符串值并将其分配给Flutter上TextField中的值

Question

我正在构建一个Gematria计算器，它按字母顺序为字母分配一个数字。我有下面的代码，我想在按下浮动按钮时返回在TextField中键入的每个字母，它已经返回了键入的值。尝试在_myController.text之后添加.toString((，但没有任何结果。我不知道该怎么做。查看代码。

class MyHomePage extends StatefulWidget {
_MyHomePageState createState() => _MyHomePageState();
@override
Widget build(BuildContext context){
return Scaffold(
backgroundColor: Colors.white,
body: Container(
child:Column(
children: <Widget>[
Align(
alignment: Alignment.center,
child: Padding(
padding: const EdgeInsets.only(top: 60),
child: Text('Decode your reality'.toUpperCase(),),
),
),
Container(
height:180,
width: MediaQuery.of(context).size.width,
padding: EdgeInsets.only(top: 40, left: 30, right: 30, bottom: 40),
child: TextField(
decoration: InputDecoration(
labelText: 'Type a word or phrase',
fillColor: Colors.white70, filled: true,
),
),
),
),
],
),
),
);
}
}
class _MyHomePageState extends State<MyHomePage> {
String a = 1.toString();
String b = 2.toString();
String c = 3.toString();
String d = 4.toString();
String e = 5.toString();
String f = 6.toString();
String g = 7.toString();
String h = 8.toString();
String i = 9.toString();
String j = 10.toString();
//...up to 26
final myController = TextEditingController();
@override
void dispose() {
myController.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.white,
body: Container(
child:Column(
children: <Widget>[
Align(
alignment: Alignment.center,
child: Padding(
padding: const EdgeInsets.only(top: 60),
child: Text('Decode your reality'),
),
),
Container(
height:180,
width: MediaQuery.of(context).size.width,
padding: EdgeInsets.only(top: 40, left: 30, right: 30, bottom: 40),
child: TextField(
controller: myController,
decoration: InputDecoration(
labelText: 'Type a word or phrase',
fillColor: Colors.white70, filled: true,
border: new OutlineInputBorder(
borderRadius: const BorderRadius.all(
const Radius.circular(10.0),
),
),
hintText: 'capital letters makes a diference'
),
),
),

Container(
child: FloatingActionButton(
onPressed: () {
return showDialog(
context: context,
builder: (context) {
return Container(
height: MediaQuery.of(context).size.height/2,
margin: EdgeInsets.only(top: 200),
decoration: new BoxDecoration(
color: Colors.white
),
child: Text( myController.text,
style: TextStyle(color: Colors.grey),
),
);
},
);
},
child: Icon(Icons.info),
),
),
],
),
)
);
}
}

提前感谢！

Answer 1

如果你想分别返回每个字母，你需要拆分用户键入的单词，过去我做了一个类似的应用程序，我对代码进行了一些调整以提供帮助：

class MyHomePage extends StatefulWidget {
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
Map<String, int> alphabet = {
'A': 1,
'B': 2,
'C': 3,
'D': 4,
'E': 5,
'F': 6,                //a map that have numbers assigned to letters
'G': 7,
'H': 8,
'I': 9,
'J': 10,
'K': 11,
'L': 12,
'M': 13,
'N': 14,
'O': 15,
'P': 16,
'Q': 17,
'R': 18,
'S': 19,
'T': 20,
'U': 21,
'V': 22,
'W': 23,
'X': 24,
'Y': 25,
'Z': 26,
};
final myController = TextEditingController();
@override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.white,
body: Container(
child: Column(
children: <Widget>[
Align(
alignment: Alignment.center,
child: Padding(
padding: const EdgeInsets.only(top: 60),
child: Text('Decode your reality'),
),
),
Container(
height: 180,
width: MediaQuery.of(context).size.width,
padding:
EdgeInsets.only(top: 40, left: 30, right: 30, bottom: 40),
child: TextField(
controller: myController,
decoration: InputDecoration(
labelText: 'Type a word or phrase',
fillColor: Colors.white70,
filled: true,
border: new OutlineInputBorder(
borderRadius: const BorderRadius.all(
const Radius.circular(10.0),
),
),
hintText: 'capital letters makes a diference'),
),
),
Container(
child: FloatingActionButton(
onPressed: () {
return showDialog(
context: context,
builder: (context) {
return Container(
height: MediaQuery.of(context).size.height / 2,
margin: EdgeInsets.only(top: 200),
decoration: new BoxDecoration(color: Colors.white),
child: Text(
decodeLetters(),     //the function being called here
style: TextStyle(color: Colors.grey),
),
);
},
);
},
child: Icon(Icons.info),
),
),
],
),
),
);
}
String decodeLetters(){                         //and the function to transform the letters
List<String> text = myController.text.split('');   //spliting the letters
List<String> decodedText = [];
for(int index = 0; index < text.length; index++){
alphabet.forEach((letter, value){           //iterating the map and comparing to the letters
if(letter == text[index].toUpperCase()){
decodedText.add(value.toString());
}
});
}
return decodedText.toString();
}
@override
void dispose() {
myController.dispose();
super.dispose();
}
}