flutter-TextField文本输入框 限制 数字键盘、输入小数点后两位

关键代码

       keyboardType: TextInputType.number,
       inputFormatters: [
           FilteringTextInputFormatter(RegExp("[0-9.]"), allow: true),
           MyNumberTextInputFormatter(digit: 2),
       ],

TextField完整代码

 1                       TextField(
 2                         controller: _money,
 3                         keyboardType: TextInputType.number,
 4                         inputFormatters: [
 5                           FilteringTextInputFormatter(RegExp("[0-9.]"), allow: true),
 6                           MyNumberTextInputFormatter(digit: 2),
 7                         ],
 8                         textAlign: TextAlign.left,
 9                         style: TextStyle(fontSize: 25.sp),
10                         decoration: InputDecoration(
11                           border: InputBorder.none,
12                           hintText: '本次最多可提现${alipayMsg['money']}元',
13                           hintStyle: TextStyle(color: Color.fromRGBO(119, 119, 119, 1), height: 1),
14                         ),
15                         autofocus: false,
16                         onChanged: (val) {
17                           money = val;
18                         },
19                       )

MyNumberTextInputFormatter完整代码

 1 import 'package:flutter/services.dart';
 2
 3 class MyNumberTextInputFormatter extends TextInputFormatter {
 4   static const defaultDouble = 0.001;
 5
 6   ///允许的小数位数，-1代表不限制位数
 7   int digit;
 8   MyNumberTextInputFormatter({this.digit = -1});
 9   static double strToFloat(String str, [double defaultValue = defaultDouble]) {
10     try {
11       return double.parse(str);
12     } catch (e) {
13       return defaultValue;
14     }
15   }
16
17   ///获取目前的小数位数
18   static int getValueDigit(String value) {
19     if (value.contains(".")) {
20       return value.split(".")[1].length;
21     } else {
22       return -1;
23     }
24   }
25
26   @override
27   TextEditingValue formatEditUpdate(TextEditingValue oldValue, TextEditingValue newValue) {
28     String value = newValue.text;
29     int selectionIndex = newValue.selection.end;
30     if (value == ".") {
31       value = "0.";
32       selectionIndex++;
33     } else if (value == "-") {
34       value = "-";
35       selectionIndex++;
36     } else if (value != "" && value != defaultDouble.toString() && strToFloat(value, defaultDouble) == defaultDouble || getValueDigit(value) > digit) {
37       value = oldValue.text;
38       selectionIndex = oldValue.selection.end;
39     }
40     return new TextEditingValue(
41       text: value,
42       selection: new TextSelection.collapsed(offset: selectionIndex),
43     );
44   }
45 }