cpd_2022_zi/lib/widgets/slider.dart

import 'package:flutter/material.dart';

double _currentSliderValue = 50;

class MySlider extends StatefulWidget {
  final String _title;
  const MySlider(this._title, {super.key});

  @override
  State<StatefulWidget> createState() => SliderState();

  double getSliderValue() {
    return _currentSliderValue;
  }
}

class SliderState extends State<MySlider> {
  TextEditingController _textFieldController = TextEditingController();
  String? _errorText;

  @override
  void initState() {
    super.initState();
    _textFieldController.text = _currentSliderValue.toString();
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        Text(widget._title),
        Row(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Slider(
                value: _currentSliderValue,
                min: 1,
                max: 100,
                divisions: 99,
                label: _currentSliderValue.round().toString(),
                onChanged: (double value) {
                  setState(() {
                    _currentSliderValue = value;
                    _textFieldController.text = _currentSliderValue.toString();
                    _errorText = null;
                  });
                }),
            Text(_currentSliderValue.round().toString())
          ],
        ),
        SizedBox(height: 16),
        TextFormField(
          controller: _textFieldController,
          keyboardType: TextInputType.number,
          decoration: InputDecoration(
            labelText: 'Enter value',
            errorText: _errorText,
          ),
          onChanged: (text) {
            if (text.isEmpty) {
              _currentSliderValue = 0;
              setState(() {
                _errorText = null;
              });
              return;
            }
            final value = double.tryParse(text);
            if (value == null || value < 1 || value > 100) {
              setState(() {
                _textFieldController.clear();
                _errorText = 'Please enter a value between 1 and 100.';
              });
              return;
            }
            setState(() {
              _currentSliderValue = value;
              _errorText = null;
            });
          },
        ),
      ],
    );
  }
}