Flutter-SearchDelegate搜索框

搜索欄

import 'package:flutter/material.dart';

typedef SearchItemCall = void Function(String item);

class SearchBarDelegate extends SearchDelegate<String> {

  @override
  List<Widget> buildActions(BuildContext context) {
    //右侧显示内容 这里放清除按钮
    return [
      IconButton(
        icon: Icon(Icons.clear),
        onPressed: () {
          query = "";
          showSuggestions(context);
        },
      ),
    ];
  }

  @override
  Widget buildLeading(BuildContext context) {
    //左侧显示内容 这里放了返回按钮
    return IconButton(
      icon: AnimatedIcon(
          icon: AnimatedIcons.menu_arrow, progress: transitionAnimation),
      onPressed: () {
        if (query.isEmpty) {
          close(context, null);
        } else {
          query = "";
          showSuggestions(context);
        }
      },
    );
  }

  @override
  Widget buildResults(BuildContext context) {
    //点击了搜索显示的页面
    return Center(
      child: Text('123'),
    );
  }

  @override
  Widget buildSuggestions(BuildContext context) {
    //点击了搜索窗显示的页面
    return SearchContentView();
  }

  @override
  ThemeData appBarTheme(BuildContext context) {
    return super.appBarTheme(context);
  }
}

class SearchContentView extends StatefulWidget {
  @override
  _SearchContentViewState createState() => _SearchContentViewState();
}

class _SearchContentViewState extends State<SearchContentView> {
  @override
  Widget build(BuildContext context) {
    return Container(
      padding: EdgeInsets.all(10),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: <Widget>[
          Container(
            child: Text(
              '大家都在搜',
              style: TextStyle(fontSize: 16),
            ),
          ),
          SearchItemView(),
          Container(
            margin: EdgeInsets.only(top: 20),
            child: Text(
              '历史记录',
              style: TextStyle(fontSize: 16),
            ),
          ),
          SearchItemView()
        ],
      ),
    );
  }
}

class SearchItemView extends StatefulWidget {
  @override
  _SearchItemViewState createState() => _SearchItemViewState();
}

class _SearchItemViewState extends State<SearchItemView> {
  List<String> items = [
    'index',
    'order',
    'main',
    '123123',
    '5test',
  ];
  @override
  Widget build(BuildContext context) {
    return Container(
      child: Wrap(
        spacing: 10,
        // runSpacing: 0,
        children: items.map((item) {
          return SearchItem(title: item);
        }).toList(),
      ),
    );
  }
}

class SearchItem extends StatefulWidget {
  @required
  final String title;
  const SearchItem({Key key, this.title}) : super(key: key);
  @override
  _SearchItemState createState() => _SearchItemState();
}

class _SearchItemState extends State<SearchItem> {
  @override
  Widget build(BuildContext context) {
    return Container(
      child: InkWell(
        child: Chip(
          label: Text(widget.title),
          shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(10)
          ),
        ),
        onTap: () {
          print(widget.title);
        },
      ),
      color: Colors.white,
    );
  }
}

main

body: Center(
          child: InkWell(
            child: Icon(Icons.search),
            onTap: (){
              showSearch(context: context,delegate: SearchBarDelegate());
            },
          )
      ),

 demo

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

class SearchBar extends StatefulWidget {
  @override
  _SearchBarState createState() => _SearchBarState();
}

class _SearchBarState extends State<SearchBar> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('SearchBar'),
        actions: <Widget>[
          IconButton(
            icon: Icon(Icons.search),
            onPressed: (){
                showSearch(context: context, delegate: SearchBarDelegate());
            },
          ),
        ],
      ),
    );
  }
}

class SearchBarDelegate extends SearchDelegate<String>{
  //重寫交叉按鈕清空數據
  @override
  List<Widget> buildActions(BuildContext context) {
    // TODO: implement buildActions
    return [
      IconButton(
        icon: Icon(Icons.clear),
        onPressed: ()=> query = '',
      )
    ];
  }
  //重寫左邊按鈕
  @override
  Widget buildLeading(BuildContext context) {
    // TODO: implement buildLeading
    return IconButton(
      icon: AnimatedIcon(
        icon: AnimatedIcons.menu_arrow,//動態圖表
        progress: transitionAnimation,
      ),
      onPressed: () => close(context,null),
    );
  }
  //重寫返回結果
  @override
  Widget buildResults(BuildContext context) {
    // TODO: implement buildResults
    return Container(
       100,
      height: 100,
      child: Card(
        color: Colors.blueAccent,
        child: Text(query),
      ),
    );
  }
  //推薦
  @override
  Widget buildSuggestions(BuildContext context) {
    final suggestionList = query.isEmpty//判斷是否為空
      ? recentSuggest:searchList.where((input)=> input.startsWith(query)).toList();
    // TODO: implement buildSuggestions
    return ListView.builder(
      itemCount: suggestionList.length,
      itemBuilder: (context,index)=>ListTile(
        title: RichText(
          text: TextSpan(
            //被搜索的
            text: suggestionList[index].substring(0,query.length),
            style: TextStyle(
              color: Colors.black,
              fontWeight: FontWeight.bold,
            ),
            //未被搜索的
            children: [
              TextSpan(
                text: suggestionList[index].substring(query.length),
                style: TextStyle(color: Colors.grey)
              )
            ]
          ),
        ),
      ),
    );
  }
}

數據

const searchList = [
  'test-1',
  'test-2',
  'test-3',
  'test-4',
  'test-5'
];

const recentSuggest = [
  '推薦 - 1',
  '推薦 - 2'
];