Slider in Flutter

Published at

10/4/2024

Categories

4 categories in total

Creating a slider in Flutter is straightforward using the Slider widget. Here’s a simple example that demonstrates how to implement a slider with a label showing the current value:

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: Text('Slider Example')),
        body: Center(
          child: SliderExample(),
        ),
      ),
    );
  }
}

class SliderExample extends StatefulWidget {
  @override
  _SliderExampleState createState() => _SliderExampleState();
}

class _SliderExampleState extends State<SliderExample> {
  double _sliderValue = 0.0;

  @override
  Widget build(BuildContext context) {
    return Column(
      mainAxisAlignment: MainAxisAlignment.center,
      children: <Widget>[
        Slider(
          value: _sliderValue,
          min: 0.0,
          max: 100.0,
          divisions: 10,
          label: _sliderValue.round().toString(),
          onChanged: (double newValue) {
            setState(() {
              _sliderValue = newValue;
            });
          },
        ),
        Text(
          'Slider Value: ${_sliderValue.round()}',
          style: TextStyle(fontSize: 20),
        ),
      ],
    );
  }
}

Explanation
Slider Widget: The main component used to create the slider.

value: Current value of the slider.

min: Minimum value the slider can take.
max: Maximum value the slider can take.
divisions: Optional. Specifies the number of discrete divisions in the slider.
label: Displays the current value of the slider when it’s moved.
onChanged: A callback that is called whenever the slider value changes. State Management: The slider value is managed using a stateful widget, allowing the UI to update whenever the slider value changes.

Text Widget: Displays the current value of the slider beneath it.

Customizing the Slider
You can customize the appearance of the slider further by adjusting properties like activeColor, inactiveColor, or using a SliderTheme. Here’s a quick example of how to customize the slider’s colors:

Slider(
  value: _sliderValue,
  min: 0.0,
  max: 100.0,
  divisions: 10,
  label: _sliderValue.round().toString(),
  activeColor: Colors.blue,
  inactiveColor: Colors.grey,
  onChanged: (double newValue) {
    setState(() {
      _sliderValue = newValue;
    });
  },
)

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Slider in Flutter