颤振 - 当文本表单字段获得焦点时，它会重置我的表单状态并导致表单重建

Question

我有一个表单，其中包含一些自定义段小部件和一些FormTextFields。 细分小部件更改了我的表单中的状态，该部分可以工作。 例如，第一个段设置_selectedBetType的值。

问题是当其中一个文本表单字段获得焦点时，_selectedBetType被设置回 0 并且表单会重新生成。

这是我的表格。

import 'package:flutter/material.dart';
import 'package:flutter/foundation.dart';
import 'package:pari/game.dart';
import 'package:pari/widgets/segment_widget.dart';

class WatchedGameForm extends StatefulWidget {
Game _game;
BetType _selectedBetType = BetType.Moneyline;
int _selectedTeamIndex = 0;
int _selectedOverUnderIndex = 0;
WatchedGameForm(this._game);
@override
State createState() =>_WatchedGameFormState();
}
class _WatchedGameFormState extends State {
final _formKey = GlobalKey();
_WatchedGameFormState();
@override
Widget build(BuildContext context) {
print(widget._selectedBetType);
return Form(
key: _formKey,
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
_buildBetTypeSegmentWidget(),
_buildTeamSegmentWidget(),
_buildOverUnderSegmentWidget(),
_buildPointsField(),
_buildOddsField(),
],
)
);
}
Widget _buildBetTypeSegmentWidget() {
return SegmentWidget(
selectedValue: widget._selectedBetType.index,
items: [
SegmentItem(BetType.Moneyline.index, describeEnum(BetType.Moneyline)),
SegmentItem(BetType.Spread.index, describeEnum(BetType.Spread)),
SegmentItem(BetType.TotalPoints.index, describeEnum(BetType.TotalPoints)),
],
onValueChanged: (int value)  {
setState(() {
widget._selectedBetType = BetType.values[value];
});
},
);
}
Widget _buildTeamSegmentWidget() {
if (widget._selectedBetType == BetType.TotalPoints)
return Container();
return SegmentWidget(
selectedValue: widget._selectedTeamIndex,
items: [
SegmentItem(0, widget._game.awayTeam),
SegmentItem(1, widget._game.homeTeam),
],
onValueChanged: (int value)  {
setState(() {
widget._selectedTeamIndex = value;
});
},
);
}
Widget _buildOverUnderSegmentWidget() {
if (widget._selectedBetType != BetType.TotalPoints)
return Container();
return SegmentWidget(
selectedValue: widget._selectedOverUnderIndex,
items: [
SegmentItem(0, "Over"),
SegmentItem(1, "Under"),
],
onValueChanged: (int value)  {
setState(() {
widget._selectedOverUnderIndex = value;
});
},
);
}
Widget _buildPointsField() {
if (widget._selectedBetType == BetType.Moneyline)
return Container();
return Padding(
padding: EdgeInsets.all(10.0),
child: TextFormField(
keyboardType: TextInputType.number,
textAlign: TextAlign.end,
decoration: InputDecoration(
labelText: (widget._selectedBetType == BetType.Spread) ? 'Point Spread' : 'Total Points',
border: OutlineInputBorder(),
)
),
);
}
Widget _buildOddsField() {
return Padding(
padding: EdgeInsets.all(10.0),
child: TextFormField(
keyboardType: TextInputType.number,
textAlign: TextAlign.end,
decoration: InputDecoration(
labelText: 'Odds',
border: OutlineInputBorder(),
)
),
);
}
}

Answer 1

这是因为你在状态之外有变量。 你可以移动，

BetType _selectedBetType = BetType.Moneyline;

里面

class _WatchedGameFormState extends State 
{
...
}