当我关注文本字段时,我需要知道如何隐藏提示文本。这是我的代码:
class _ContactoState extends State<Contacto> {
FocusNode focusMsj;
@override
void initState() {
super.initState();
focusMsj = FocusNode();
focusMsj.addListener(() {
if (!focusMsj.hasFocus) {
FocusScope.of(context).requestFocus(focusMsj);
}
});
}
TextField(
focusNode: focusMsj,
hintText: focusMsj.hasFocus ? ' ' : 'Hint Text',)
return WillPopScope(
child: Listener(
onPointerUp: (e) {
focusMsj.hasFocus ? FocusScope.of(context).requestFocus(FocusNode()): '';
},
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谢谢
我需要有关此功能的帮助。当我在文本字段中输入文本时,我需要您在输入另一个文本字段时验证该文本。
这是我的代码
class _ProfileState extends State<Profile> {
bool _hasInputError = false;
var idNumber = '';
var nombreUser = "";
FocusNode focusNode;
void initState() {
super.initState();
focusNode = new FocusNode();
focusNode.addListener(() {
if (!focusNode.hasFocus) {
setState(() {
_hasInputError = idNumber.length < 3;
});
}
});
}
@override
Widget build(BuildContext context) {
final nombreUserField = TextField(
focusNode: _focusNode,
onChanged: (String text) {
nombreUser = text;
},
);
final idNumberElement = TextField(
focusNode: _focusNode,
decoration: InputDecoration(
errorText: _hasInputError ? "Id is too short" …Run Code Online (Sandbox Code Playgroud) 我正在使用这种方法并收到此消息。我该如何纠正?
此函数的返回类型为“Future”,但不以 return 语句结尾。尝试添加 return 语句,或将返回类型更改为“void”。
Future<bool> _onWillPop() {
Navigator.of(context).pop(false);
Navigator.pushNamed(context, '/home');}
return WillPopScope(
onWillPop: _onWillPop,
child: Scaffold
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谢谢!