flutter - lib/widgets/textFieldWidgetStyle1.dart:22:18:错误:参数类型“函数”不能分配给参数类型“无效函数(字符串)?”
问题描述
我只想将此函数变量分配给 onChanged 事件,但它不断抛出错误
class TextFieldWidget extends StatelessWidget {
final String hintText;
final IconData prefixIcon;
final IconData suffixIconData;
final bool obscure;
final Function onTextChanged;
const TextFieldWidget({
Key? key,
required this.hintText,
required this.prefixIcon,
required this.suffixIconData,
required this.obscure,
required this.onTextChanged,
}) : super(key: key);
@override
Widget build(BuildContext context) {
return TextField(
onChanged: onTextChanged,
style: TextStyle(
color: Colors.orange,
fontSize: 14.0,
),
我试着在这里调用它
TextFieldWidget(
hintText: 'Email',
obscure: false,
prefixIcon: Icons.email,
suffixIconData: Icons.arrow_back,
onTextChanged: (Value) => homeModel.isVisable(Value),
)
..
这是家庭模型
class HomeModel extends ChangeNotifier {
//password is visable ?? the user must set this as activated by clicking the visable icon
get isVisable => _isVisable;
bool _isVisable = false;
set isVisable(value) {
_isVisable = value;
notifyListeners();
}
//if email is valid set change
get isValid => _isVisable;
// ignore: unused_field
bool _isValid = false;
void isValidEmail(String input) {
if (input == Global.ValidEmail.first) {
_isValid = true;
} else {
_isValid = false;
}
notifyListeners();
}
}
这是确切的错误 lib/widgets/textFieldWidgetStyle1.dart:22:18: Error: The argument type 'Function' can't be assigned to the parameter type 'void Function(String)?'。
- “功能”来自“飞镖:核心”。onChanged: onTextChanged,
解决方案
改变
onChanged: onTextChanged,
至
onChanged: onTextChanged as void Function(String)?,
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