Flatternformvalidierung
final _formKey = GlobalKey<FormState>();
@override
Widget build(BuildContext context) {
// Build a Form widget using the _formKey created above.
return Form(
key: _formKey,
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
TextFormField(
// The validator receives the text that the user has entered.
validator: (value) {
if (value == null || value.isEmpty) {
return 'Please enter some text';
}
return null;
},
),
Padding(
padding: const EdgeInsets.symmetric(vertical: 16.0),
child: ElevatedButton(
onPressed: () {
// Validate returns true if the form is valid, or false otherwise.
if (_formKey.currentState!.validate()) {
// If the form is valid, display a snackbar. In the real world,
// you'd often call a server or save the information in a database.
ScaffoldMessenger.of(context).showSnackBar(
const SnackBar(content: Text('Processing Data')),
);
}
},
child: const Text('Submit'),
),
),
],
),
);
Sore Seahorse