我正在尝试设置我在地址中键入的字段的样式，我想减小字体大小。我尝试通过“ Inputdecoration”中的各种“ textstyle”属性来更改fontsize，但是没有运气。我该如何实现？
这些黄线也突出了我的文字。这是错误吗？
请帮助我：/非常感谢〜
return MaterialApp(
home: Scaffold(
body: Stack(
children: <Widget>[
GoogleMap(
onMapCreated: (GoogleMapController controller) {
mapController = controller;
},
initialCameraPosition: currentPosition,
markers: marks,
),
SafeArea(
child: Padding(
padding: const EdgeInsets.all(8.0),
child: PlacesAutocompleteField(
apiKey: 'AIzaSyDVxxxxxxxxxxxxxx',
hint: 'Search Places',
style: TextStyle(fontSize: 50.0),
inputDecoration: InputDecoration(
icon: Icon(Icons.search),
hintStyle: TextStyle(
fontSize: 50.0,
fontWeight: FontWeight.bold,
),
),
onChanged: (value) async {
placeName = value;
print(placeName);
List<Placemark> placemark =
await Geolocator().placemarkFromAddress(placeName);
print(placemark[0].position);
Set<Marker> markers =
await getMarkers(placemark[0].position);
updateUI(placemark[0].position, markers);
mapController.animateCamera(
CameraUpdate.newCameraPosition(currentPosition));
},
),
),
),
],
),
),
);
PlacesAutocompleteField的代码：
class PlacesAutocompleteField extends StatefulWidget {
/// Creates a text field like widget.
///
/// To remove the decoration entirely (including the extra padding introduced
/// by the decoration to save space for the labels), set the [decoration] to
/// null.
const PlacesAutocompleteField({
Key key,
@required this.apiKey,
this.style,
this.controller,
this.leading,
this.hint = "Search",
this.trailing,
this.trailingOnTap,
this.mode = Mode.fullscreen,
this.offset,
this.location,
this.radius,
this.language,
this.sessionToken,
this.types,
this.components,
this.strictbounds,
this.onChanged,
this.onError,
this.inputDecoration = const InputDecoration(),
}) : super(key: key);
/// Controls the text being edited.
///
/// If null, this widget will create its own [TextEditingController].
final TextEditingController controller;
/// Icon shown inside the field left to the text.
final Icon leading;
/// Icon shown inside the field right to the text.
final Icon trailing;
/// Callback when [trailing] is tapped on.
final VoidCallback trailingOnTap;
/// Text that is shown, when no input was done, yet.
final String hint;
final TextStyle style;
/// Your Google Maps Places API Key.
///
/// For this key the Places Web API needs to be activated. For further
/// information on how to do this, see their official documentation below.
///
/// See also:
///
/// * <https://developers.google.com/places/web-service/autocomplete>
final String apiKey;
/// The decoration to show around the text field.
///
/// By default, draws a horizontal line under the autocomplete field but can be
/// configured to show an icon, label, hint text, and error text.
///
/// Specify null to remove the decoration entirely (including the
/// extra padding introduced by the decoration to save space for the labels).
final InputDecoration inputDecoration;
/// The position, in the input term, of the last character that the service
/// uses to match predictions.
///
/// For example, if the input is 'Google' and the
/// offset is 3, the service will match on 'Goo'. The string determined by the
/// offset is matched against the first word in the input term only. For
/// example, if the input term is 'Google abc' and the offset is 3, the service
/// will attempt to match against 'Goo abc'. If no offset is supplied, the
/// service will use the whole term. The offset should generally be set to the
/// position of the text caret.
///
/// Source: https://developers.google.com/places/web-service/autocomplete
final num offset;
final Mode mode;
final String language;
final String sessionToken;
final List<String> types;
final List<Component> components;
final Location location;
final num radius;
final bool strictbounds;
/// Called when the text being edited changes.
final ValueChanged<String> onChanged;
/// Callback when autocomplete has error.
final ValueChanged<PlacesAutocompleteResponse> onError;
@override
_LocationAutocompleteFieldState createState() =>
_LocationAutocompleteFieldState();
}
class _LocationAutocompleteFieldState extends State<PlacesAutocompleteField> {
TextEditingController _controller;
TextEditingController get _effectiveController =>
widget.controller ?? _controller;
@override
void initState() {
super.initState();
if (widget.controller == null) _controller = TextEditingController();
}
@override
void didUpdateWidget(PlacesAutocompleteField oldWidget) {
super.didUpdateWidget(oldWidget);
if (widget.controller == null && oldWidget.controller != null)
_controller = TextEditingController.fromValue(oldWidget.controller.value);
else if (widget.controller != null && oldWidget.controller == null)
_controller = null;
}
Future<Prediction> _showAutocomplete() async => PlacesAutocomplete.show(
context: context,
apiKey: widget.apiKey,
offset: widget.offset,
onError: widget.onError,
mode: widget.mode,
hint: widget.hint,
language: widget.language,
sessionToken: widget.sessionToken,
components: widget.components,
location: widget.location,
radius: widget.radius,
types: widget.types,
strictbounds: widget.strictbounds,
);
void _handleTap() async {
Prediction p = await _showAutocomplete();
if (p == null) return;
setState(() {
_effectiveController.text = p.description;
if (widget.onChanged != null) {
widget.onChanged(p.description);
}
});
}
@override
Widget build(BuildContext context) {
final TextEditingController controller = _effectiveController;
var text = controller.text.isNotEmpty
? Text(
controller.text,
softWrap: true,
)
: Text(
widget.hint ?? '',
style: TextStyle(color: Colors.black38),
);
Widget child = Row(
children: <Widget>[
widget.leading ?? SizedBox(),
SizedBox(
width: 16.0,
),
Expanded(
child: text,
),
widget.trailing != null
? GestureDetector(
onTap: widget.trailingOnTap,
child: widget.trailingOnTap != null
? widget.trailing
: Icon(
widget.trailing.icon,
color: Colors.grey,
),
)
: SizedBox()
],
);
if (widget.inputDecoration != null) {
child = InputDecorator(
decoration: widget.inputDecoration,
child: child,
);
}
return GestureDetector(
behavior: HitTestBehavior.translucent,
onTap: _handleTap,
child: child,
);
}
}
答案 0 :(得分：2)
原因是您没有为Text提供任何具有实质性设计的小部件，因此有很多方法可以对其进行修复，例如您可以提供Material或基本的Scaffold 。推荐的方法是使用Scaffold，因为它也可以提供许多基本功能。
因此，您需要将Stack包裹在Scaffold
Scaffold(
body: Stack(...)
)
更新（针对文本大小）：
在build()类的PlacesAutocompleteField方法中，将您的替换为以下
var text = controller.text.isNotEmpty
? Text(
controller.text,
softWrap: true,
style: TextStyle(fontSize: 50),
)
: Text(
widget.hint ?? '',
style: TextStyle(color: Colors.black38, fontSize: 50),
);