在SearchDelegate
的当前实现中,没有任何选项可以更改提示文本。查询为空时,搜索屏幕在查询字段中显示“ Search”作为提示文本。
当前在第395行上如下定义提示文本:
final String searchFieldLabel = MaterialLocalizations.of(context).searchFieldLabel;
但是有existing issue to this subject reported。
我无法为此提出任何解决方案。您知道该问题的任何解决方法吗?
通过创建自己的DefaultMaterialLocalizations
类并将其传递到MaterialApp
小部件中,可以解决此问题:
void main() => runApp(SearchApp());
class SearchApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
localizationsDelegates: [
CustomLocalizationDelegate(),
],
home: Scaffold(
appBar: AppBar(
title: Text('Search demo'),
),
body: Center(
child: Builder(
builder: (context) => MaterialButton(
child: Text('Search'),
onPressed: () => showSearch(
context: context,
delegate: DummyDelegate(),
),
),
),
),
),
);
}
}
class DummyDelegate extends SearchDelegate<String> {
@override
List<Widget> buildActions(BuildContext context) => [];
@override
Widget buildLeading(BuildContext context) => IconButton(
icon: Icon(Icons.close),
onPressed: () => Navigator.of(context).pop(),
);
@override
Widget buildResults(BuildContext context) => Text('Result');
@override
Widget buildSuggestions(BuildContext context) => Text('Suggestion');
}
class CustomLocalizationDelegate extends LocalizationsDelegate<MaterialLocalizations> {
const CustomLocalizationDelegate();
@override
bool isSupported(Locale locale) => locale.languageCode == 'en';
@override
Future<MaterialLocalizations> load(Locale locale) => SynchronousFuture<MaterialLocalizations>(const CustomLocalization());
@override
bool shouldReload(CustomLocalizationDelegate old) => false;
@override
String toString() => 'CustomLocalization.delegate(en_US)';
}
class CustomLocalization extends DefaultMaterialLocalizations {
const CustomLocalization();
@override
String get searchFieldLabel => "My hint text";
}
当前SearchDelegate具有可选成员“ searchFieldLabel”,用于指定搜索字段的标签。它应该看起来像这样:
@override
String get searchFieldLabel => 'custom label';
就提示色而言,如果您仍在寻找解决方案,则HintColor将无法正常工作。像这样使用ThemeData的InputDecoration属性:
inputDecorationTheme: InputDecorationTheme(hintStyle: Theme.of(context).textTheme.title.copyWith(color: Colors.white),)