我是 Flutter 世界的新手
我嘗試用這種方式直接指向`TextFormField，標題中出現了這個錯誤
我想使用方向性textDirection: TextDirection.rtl，
但這就是發生的事情
Widget _buildName() {
Directionality(
textDirection: TextDirection.rtl,
child: TextFormField(
textAlign: TextAlign.right,
decoration: InputDecoration(labelText: '?????', hintText: '???? ????'),
maxLength: 10,
validator: (String? value) {
if (value!.isEmpty) {
return '??? ?? ?? ???? ????? ??????';
}
return null;
},
onSaved: (String? value) {
_name = value;
},
));
}
uj5u.com熱心網友回復：
您收到錯誤是因為您沒有回傳任何內容。return在 Directionality() 之前添加關鍵字，它應該可以作業：
Widget _buildName() {
return Directionality(
textDirection: TextDirection.rtl,
child: TextFormField(
textAlign: TextAlign.right,
decoration: InputDecoration(labelText: '?????', hintText: '???? ????'),
maxLength: 10,
validator: (String? value) {
if (value!.isEmpty) {
return '??? ?? ?? ???? ????? ??????';
}
return null;
},
onSaved: (String? value) {
_name = value;
},
));
}uj5u.com熱心網友回復：
嘗試這個
Widget _buildName() {
Directionality(
textDirection: TextDirection.rtl,
child: TextFormField(
textAlign: TextAlign.right,
decoration: InputDecoration(labelText: '?????', hintText: '???? ????'),
maxLength: 10,
validator: (String? value) {
if (value!.isEmpty) {
return '??? ?? ?? ???? ????? ??????';
}
return '';///here
},
onSaved: (String? value) {
_name = value;
},
));
}
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標籤：扑无效的颤振文本表单字段