探索 Flutter Picker：一个高效、灵活的下拉选择组件

import 'package:flutter/material.dart';
import 'package:flutter_picker/flutter_picker.dart';
 
class PickerExample extends StatefulWidget {
  @override
  _PickerExampleState createState() => _PickerExampleState();
}
 
class _PickerExampleState extends State<PickerExample> {
  // 选择器的数据
  List<String> fruits = ['Apple', 'Banana', 'Cherry'];
  List<String> colors = ['Red', 'Yellow', 'Purple'];
 
  // 选择器当前选中的值
  String selectedFruit;
  String selectedColor;
 
  // 选择器的显示与隐藏状态
  bool isFruitPickerShown = false;
  bool isColorPickerShown = false;
 
  void showPicker(List<String> items, String currentValue, bool isShown, ValueChanged<String> onChanged) {
    Picker(
      adapter: PickerAdapter(pickerData: items),
      selecteds: items.indexOf(currentValue),
      onConfirm: (Picker picker, List<int> selecteds) {
        onChanged(items[selecteds[0]]);
        Navigator.of(context).pop(); // 关闭选择器
      },
    ).showModal(context);
  }
 
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Picker Example'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text('Selected Fruit: $selectedFruit'),
            SizedBox(height: 20.0),
            Text('Selected Color: $selectedColor'),
            SizedBox(height: 20.0),
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: <Widget>[
                FlatButton(
                  child: Text('Select Fruit'),
                  onPressed: () {
                    showPicker(fruits, selectedFruit ?? fruits.first, isFruitPickerShown, (newValue) {
                      setState(() {
                        selectedFruit = newValue;
                      });
                    });
                  },
                ),
                SizedBox(width: 20.0),
                FlatButton(
                  child: Text('Select Color'),
                  onPressed: () {
                    showPicker(colors, selectedColor ?? colors.first, isColorPickerShown, (newValue) {
                      setState(() {
                        selectedColor = newValue;
                      });
                    });
                  },
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

这段代码使用了\`f