Flutter自动补全翻转插件flutter_flipped_autocomplete的使用

Flutter自动补全翻转插件flutter_flipped_autocomplete的使用

在Flutter开发过程中，有时我们需要一个自动补全功能，并且希望选项出现在文本框上方。这可以通过flutter_flipped_autocomplete插件来实现。以下是如何使用该插件的详细指南。

1. 添加依赖

首先，在你的pubspec.yaml文件中添加flutter_flipped_autocomplete依赖：

dependencies:
  flutter:
    sdk: flutter
  flutter_flipped_autocomplete: ^1.0.0

然后运行flutter pub get命令以安装该依赖。

2. 使用示例

接下来，我们来看一个完整的示例代码，展示如何在Flutter应用中使用flutter_flipped_autocomplete插件。

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

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Flipped Autocomplete 示例'),
        ),
        body: Padding(
          padding: EdgeInsets.all(16.0),
          child: FlippedAutocomplete<String>(
            optionsViewBuilder: (context, onSelected, options) {
              return ListView.builder(
                itemCount: options.length,
                itemBuilder: (BuildContext context, int index) {
                  final String option = options.elementAt(index);
                  return ListTile(
                    title: Text(option),
                    onTap: () {
                      onSelected(option);
                    },
                  );
                },
              );
            },
            optionsBuilder: (TextEditingValue textEditingValue) {
              if (textEditingValue.text == '') {
                return const Iterable<String>.empty();
              }
              return ['Apple', 'Banana', 'Cherry', 'Date', 'Elderberry']
                  .where((String option) => option.contains(textEditingValue.text.toLowerCase()));
            },
            onSelected: (String selection) {
              print('Selected: $selection');
            },
            decoration: InputDecoration(
              labelText: '输入水果名称',
              border: OutlineInputBorder(),
            ),
          ),
        ),
      ),
    );
  }
}

3. 代码解释

• 导入必要的库：

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

• 定义主应用类：

  void main() {
    runApp(MyApp());
  }
  
  class MyApp extends StatelessWidget {
    @override
    Widget build(BuildContext context) {
      return MaterialApp(
        home: Scaffold(
          appBar: AppBar(
            title: Text('Flipped Autocomplete 示例'),
          ),
          body: Padding(
            padding: EdgeInsets.all(16.0),
            child: FlippedAutocomplete<String>(
              // 插件核心配置
            ),
          ),
        ),
      );
    }
  }
  

• 配置FlippedAutocomplete组件：

  FlippedAutocomplete<String>(
    optionsViewBuilder: (context, onSelected, options) {
      // 自定义下拉选项视图
      return ListView.builder(
        itemCount: options.length,
        itemBuilder: (BuildContext context, int index) {
          final String option = options.elementAt(index);
          return ListTile(
            title: Text(option),
            onTap: () {
              onSelected(option);
            },
          );
        },
      );
    },
    optionsBuilder: (TextEditingValue textEditingValue) {
      // 定义搜索逻辑
      if (textEditingValue.text == '') {
        return const Iterable<String>.empty();
      }
      return ['Apple', 'Banana', 'Cherry', 'Date', 'Elderberry']
          .where((String option) => option.contains(textEditingValue.text.toLowerCase()));
    },
    onSelected: (String selection) {
      // 用户选择后的回调
      print('Selected: $selection');
    },
    decoration: InputDecoration(
      labelText: '输入水果名称',
      border: OutlineInputBorder(),
    ),
  )