表单验证
class FormWidget extends StatefulWidget
{
@override
_FormWidgetState
createState() => _FormWidgetState();
}
class _FormWidgetState extends State
<FormWidget
> {
GlobalKey
<FormState
> formGlobalKey
= GlobalKey
<FormState
>();
String userName
;
String pwd
;
void save() {
var form
= formGlobalKey
.currentState
;
if (form
.validate()) {
form
.save();
print(userName
+ "," + pwd
);
}
}
void reset() {
var form
= formGlobalKey
.currentState
;
form
.reset();
}
@override
Widget
build(BuildContext context
) {
return Form(
key
: formGlobalKey
,
child
: Column(
children
: [
TextFormField(
decoration
: InputDecoration(
labelText
: "姓名",
),
validator
: (content
) {
if (content
.length
> 8) {
return "姓名过长";
} else if (content
.length
<= 0) {
return "姓名过短";
}
},
onSaved
: (value
) {
userName
= value
;
},
),
TextFormField(
obscureText
: true,
decoration
: InputDecoration(
labelText
: "密码",
),
validator
: (content
) {
if (content
.length
< 8) {
return "密码过短";
}
},
onSaved
: (value
) {
pwd
= value
;
},
),
RaisedButton(
onPressed
: save
,
child
: Text("保存"),
),
RaisedButton(
onPressed
: reset
,
child
: Text("重置"),
)
],
),
);
}
}
