Toggle Bar In Flutter

Toggle Bar In Flutter :

Screenshot :

Toggle Bar In Flutter

toggle_bar.dart

library toggle_bar;

import 'dart:collection';

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

class ToggleBar extends StatefulWidget {
  final TextStyle labelTextStyle;
  final Color backgroundColor;
  final BoxBorder backgroundBorder;
  final Color selectedTabColor;
  final Color selectedTextColor;
  final Color textColor;
  final List<String> labels;
  final Function(int) onSelectionUpdated;

  ToggleBar(
      {@required this.labels,
      this.backgroundColor = Colors.black,
      this.backgroundBorder,
      this.selectedTabColor = Colors.deepPurple,
      this.selectedTextColor = Colors.white,
      this.textColor = Colors.black,
      this.labelTextStyle = const TextStyle(),
      this.onSelectionUpdated});

  @override
  State<StatefulWidget> createState() {
    return _ToggleBarState();
  }
}

class _ToggleBarState extends State<ToggleBar> {
  LinkedHashMap<String, bool> _hashMap = LinkedHashMap();
  int _selectedIndex = 0;

  @override
  void initState() {
    _hashMap = LinkedHashMap.fromIterable(widget.labels,
        value: (value) => value = false);
    _hashMap[widget.labels[0]] = true;

    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Container(
        height: 48,
        margin: EdgeInsets.all(8.0),
        padding: EdgeInsets.all(8.0),
        decoration: BoxDecoration(
            color: widget.backgroundColor,
            border: widget.backgroundBorder,
            borderRadius: BorderRadius.circular(50)),
        child: ListView.builder(
            itemCount: widget.labels.length,
            scrollDirection: Axis.horizontal,
            itemBuilder: (context, index) {
              return GestureDetector(
                  child: Container(
                      width: (MediaQuery.of(context).size.width - 32) /
                          widget.labels.length,
                      padding:
                          EdgeInsets.only(left: 8, right: 8, top: 8, bottom: 8),
                      child: Text(_hashMap.keys.elementAt(index),
                          textAlign: TextAlign.center,
                          style: widget.labelTextStyle.apply(
                              color: _hashMap.values.elementAt(index)
                                  ? widget.selectedTextColor
                                  : widget.textColor)),
                      decoration: BoxDecoration(
                          color: _hashMap.values.elementAt(index)
                              ? widget.selectedTabColor
                              : null,
                          borderRadius: BorderRadius.circular(50))),
                  onHorizontalDragUpdate: (dragUpdate) async {
                    int calculatedIndex = ((widget.labels.length *
                                    (dragUpdate.globalPosition.dx /
                                        (MediaQuery.of(context).size.width -
                                            32)))
                                .round() -
                            1)
                        .clamp(0, widget.labels.length - 1);

                    if (calculatedIndex != _selectedIndex) {
                      _updateSelection(calculatedIndex);
                    }
                  },
                  onTap: () async {
                    if (index != _selectedIndex) {
                      _updateSelection(index);
                    }
                  });
            }));
  }

  _updateSelection(int index) {
    setState(() {
      _selectedIndex = index;
      widget.onSelectionUpdated(_selectedIndex);
      _hashMap.updateAll((label, selected) => selected = false);
      _hashMap[_hashMap.keys.elementAt(index)] = true;
    });
  }
}

main.dart

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

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Tutorial',
      theme: ThemeData(
        primarySwatch: Colors.deepPurple,
      ),
      debugShowCheckedModeBanner: false,
      home: MyHomePage(title: 'Toggle Bar in Flutter'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  List<String> labels = ["Apples", "Bananas", "Oranges", "Papayas"];
  int currentIndex = 0;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text(widget.title),
        ),
        body: Column(
            mainAxisAlignment: MainAxisAlignment.start,
            children: <Widget>[
              ToggleBar(
                labels: labels,
                backgroundColor: Colors.grey.withOpacity(0.1),
                onSelectionUpdated: (index) =>
                    setState(() => currentIndex = index),
              ),
              Text(
                labels[currentIndex],
                style: Theme.of(context).textTheme.display1,
              )
            ]));
  }
}

The flutter tutorial  is a website that bring you the latest and amazing resources of code. All the languages codes are included in this website. The languages like flutter, android, java,kotlin etc.with the help of this languages any user can develop the beautiful application

For more information about Flutter. visit www.fluttertutorial.in