[英]How to change SearchDelegate StatusBarIcons Color or buildSuggestions body Color in flutter?
[英]how to trigger search automatically when using SearchDelegate buildSuggestions in flutter
現在我在 flutter 2.0.1 中使用 SearchDelegate,這是我的 buildSuggestions 代碼:
@override
Widget buildSuggestions(BuildContext context) {
var channelRequest = new ChannelRequest(pageNum: 1, pageSize: 10, name: query);
if (query.isEmpty) {
return Container();
}
return FutureBuilder(
future: ChannelAction.fetchSuggestion(channelRequest),
builder: (context, AsyncSnapshot snapshot) {
if (snapshot.hasData) {
List<ChannelSuggestion> suggestions = snapshot.data;
return buildSuggestionComponent(suggestions, context);
} else {
return Text("");
}
});
}
Widget buildSuggestionComponent(List<ChannelSuggestion> suggestions, BuildContext context) {
return ListView.builder(
itemCount: suggestions.length,
itemBuilder: (context, index) {
return ListTile(
title: Text('${suggestions[index].name}'),
onTap: () async {
query = '${suggestions[index].name}';
},
);
},
);
}
當 select 是推薦文本時,我想自動觸發搜索事件(當我點擊建議文本時,觸發搜索,從服務器端獲取數據並將結果呈現給用戶界面)所以我不需要點擊搜索按鈕。 這是我的搜索代碼:
@override
Widget buildResults(BuildContext context) {
var channelRequest = new ChannelRequest(pageNum: 1, pageSize: 10, name: query);
return buildResultImpl(channelRequest);
}
Widget buildResultImpl(ChannelRequest channelRequest) {
return FutureBuilder(
future: ChannelAction.searchChannel(channelRequest),
builder: (context, AsyncSnapshot snapshot) {
if (snapshot.hasData) {
List<Channel> channels = snapshot.data;
return buildResultsComponent(channels, context);
} else {
return Text("");
}
return Center(child: CircularProgressIndicator());
});
}
我應該怎么做才能實施它? 我試過在 buildSuggestionComponent 中調用buildResults
buildSuggestionComponent
但它似乎不起作用。
要根據查詢更新數據,您可以在單擊建議時調用 API 以獲取結果,然后使用StreamController
將 stream 的結果傳遞給buildResults()
方法並調用showResults()
。
我在這里創建一個簡單的應用程序進行演示:
import 'dart:async';
import 'package:flutter/material.dart';
void main() {
runApp(MaterialApp(home: Home()));
}
class Home extends StatefulWidget {
@override
_HomeState createState() => _HomeState();
}
class _HomeState extends State<Home> {
final _controller = StreamController.broadcast();
@override
dispose() {
super.dispose();
_controller.close();
}
Future<void> _showSearch() async {
await showSearch(
context: context,
delegate: TheSearch(context: context, controller: _controller),
query: "any query",
);
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Search Demo"),
actions: <Widget>[
IconButton(
icon: Icon(Icons.search),
onPressed: _showSearch,
),
],
),
);
}
}
class TheSearch extends SearchDelegate<String> {
TheSearch({this.context, this.controller});
BuildContext context;
StreamController controller;
final suggestions =
List<String>.generate(10, (index) => 'Suggestion ${index + 1}');
@override
List<Widget> buildActions(BuildContext context) {
return [IconButton(icon: Icon(Icons.clear), onPressed: () => query = "")];
}
@override
Widget buildLeading(BuildContext context) {
return IconButton(
icon: AnimatedIcon(
icon: AnimatedIcons.menu_arrow,
progress: transitionAnimation,
),
onPressed: () {
close(context, null);
},
);
}
@override
Widget buildResults(BuildContext context) {
return StreamBuilder(
stream: controller.stream,
builder: (context, snapshot) {
if (!snapshot.hasData)
return Container(
child: Center(
child: Text('Empty result'),
));
return Column(
children: List<Widget>.generate(
snapshot.data.length,
(index) => ListTile(
onTap: () => close(context, snapshot.data[index]),
title: Text(snapshot.data[index]),
),
),
);
},
);
}
@override
Widget buildSuggestions(BuildContext context) {
final _suggestions = query.isEmpty ? suggestions : [];
return ListView.builder(
itemCount: _suggestions.length,
itemBuilder: (content, index) => ListTile(
onTap: () {
query = _suggestions[index];
// Make your API call to get the result
// Here I'm using a sample result
controller.add(sampleResult);
showResults(context);
},
title: Text(_suggestions[index])),
);
}
}
final List<String> sampleResult =
List<String>.generate(10, (index) => 'Result ${index + 1}');
我已經通過一個簡單的解決方法完成了
只需在數據庫調用后添加此行
query = query
但要小心調用循環
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.