搜索条

模拟数据 asset.dart

const searchList = [
  "jiejie-大长腿",
  "jiejie-水蛇腰",
  "gege1-帅气欧巴",
  "gege2-小鲜肉"
];

const recentSuggest = [
  "推荐-1",
  "推荐-2"
];

自定义Class SearchBarDelegate继承自 SearchDelegate,并重写四个方法

import 'package:flutter/material.dart';
import 'asset.dart';


class SearchBarDemo extends StatefulWidget {
  _SearchBarDemoState createState() => _SearchBarDemoState();
}

class _SearchBarDemoState extends State {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar:AppBar(
        title:Text('SearchBarDemo'),
        actions:[
          IconButton(
            icon:Icon(Icons.search),
            onPressed: (){
               showSearch(context:context,delegate: searchBarDelegate());
            }
            // showSearch(context:context,delegate: searchBarDelegate()),
          ),
        ]
      )
    );

  }
}

class searchBarDelegate extends SearchDelegate{

//右侧清空按钮
  @override
  List buildActions(BuildContext context){
    return [
      IconButton(
        icon:Icon(Icons.clear),
        onPressed: ()=>query = "",)
      ];
  }
  
  //左侧返回按钮
  @override
  Widget buildLeading(BuildContext context) {
    return IconButton(
        icon: AnimatedIcon(
            icon: AnimatedIcons.menu_arrow, progress: transitionAnimation),
        onPressed: () => close(context, null));
  }


//搜索到内容的展示
  @override
  Widget buildResults(BuildContext context) {
    return Container(
      width: 100.0,
      height: 100.0,
      child: Card(
        color: Colors.redAccent,
        child: Center(
          child: Text(query),
        ),
      ),
    );
  }


//推荐展示
   @override
  Widget buildSuggestions(BuildContext context) {
    final suggestionList = query.isEmpty
        ? recentSuggest
        : searchList.where((input) => input.startsWith(query)).toList();
    return ListView.builder(
        itemCount: suggestionList.length,
        itemBuilder: (context, index) => ListTile(
              title: RichText(
                  text: TextSpan(
                      text: suggestionList[index].substring(0, query.length),
                      style: TextStyle(
                          color: Colors.black, fontWeight: FontWeight.bold),
                      children: [
                    TextSpan(
                        text: suggestionList[index].substring(query.length),
                        style: TextStyle(color: Colors.grey))
                  ])),
            ));
  }


}  

标题

调用

showSearch(context:context,delegate:searchBarDelegate());