// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Flutter code sample for [NavigationRail].

import 'package:flutter/material.dart';

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

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return const MaterialApp(
      home: NavRailExample(),
    );
  }
}

class NavRailExample extends StatefulWidget {
  const NavRailExample({super.key});

  @override
  State<NavRailExample> createState() => _NavRailExampleState();
}

class _NavRailExampleState extends State<NavRailExample> {
  int _selectedIndex = 0;
  NavigationRailLabelType labelType = NavigationRailLabelType.all;
  bool showLeading = false;
  bool showTrailing = false;
  double groupAligment = -1.0;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Row(
        children: <Widget>[
          NavigationRail(
            selectedIndex: _selectedIndex,
            groupAlignment: groupAligment,
            onDestinationSelected: (int index) {
              setState(() {
                _selectedIndex = index;
              });
            },
            labelType: labelType,
            leading: showLeading ? FloatingActionButton(
              elevation: 0,
              onPressed: () {
                // Add your onPressed code here!
              },
              child: const Icon(Icons.add),
              ) : const SizedBox(),
            trailing: showTrailing ? IconButton(
              onPressed: () {
                // Add your onPressed code here!
              },
              icon: const Icon(Icons.more_horiz_rounded),
              ) : const SizedBox(),
            destinations: const <NavigationRailDestination>[
              NavigationRailDestination(
                icon: Icon(Icons.favorite_border),
                selectedIcon: Icon(Icons.favorite),
                label: Text('First'),
              ),
              NavigationRailDestination(
                icon: Icon(Icons.bookmark_border),
                selectedIcon: Icon(Icons.book),
                label: Text('Second'),
              ),
              NavigationRailDestination(
                icon: Icon(Icons.star_border),
                selectedIcon: Icon(Icons.star),
                label: Text('Third'),
              ),
            ],
          ),
          const VerticalDivider(thickness: 1, width: 1),
          // This is the main content.
            Expanded(
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: <Widget>[
                  Text('selectedIndex: $_selectedIndex'),
                  const SizedBox(height: 20),
                  Text('Label type: ${labelType.name}'),
                  const SizedBox(height: 10),
                  OverflowBar(
                    spacing: 10.0,
                    children: <Widget>[
                      ElevatedButton(
                        onPressed: () {
                          setState(() {
                            labelType = NavigationRailLabelType.none;
                          });
                        },
                        child: const Text('None'),
                      ),
                      ElevatedButton(
                        onPressed: () {
                          setState(() {
                            labelType = NavigationRailLabelType.selected;
                          });
                        },
                        child: const Text('Selected'),
                      ),
                      ElevatedButton(
                        onPressed: () {
                          setState(() {
                            labelType = NavigationRailLabelType.all;
                          });
                        },
                        child: const Text('All'),
                      ),
                    ],
                  ),
                  const SizedBox(height: 20),
                  Text('Group alignment: $groupAligment'),
                  const SizedBox(height: 10),
                  OverflowBar(
                    spacing: 10.0,
                    children: <Widget>[
                      ElevatedButton(
                        onPressed: () {
                          setState(() {
                            groupAligment = -1.0;
                          });
                        },
                        child: const Text('Top'),
                      ),
                      ElevatedButton(
                        onPressed: () {
                          setState(() {
                            groupAligment = 0.0;
                          });
                        },
                        child: const Text('Center'),
                      ),
                      ElevatedButton(
                        onPressed: () {
                          setState(() {
                            groupAligment = 1.0;
                          });
                        },
                        child: const Text('Bottom'),
                      ),
                    ],
                  ),
                  const SizedBox(height: 20),
                  OverflowBar(
                    spacing: 10.0,
                    children: <Widget>[
                      ElevatedButton(
                        onPressed: () {
                          setState(() {
                            showLeading = !showLeading;
                          });
                        },
                        child: Text(showLeading ? 'Hide Leading' : 'Show Leading'),
                      ),
                      ElevatedButton(
                        onPressed: () {
                          setState(() {
                            showTrailing = !showTrailing;
                          });
                        },
                        child: Text(showTrailing ? 'Hide Trailing' : 'Show Trailing'),
                      ),
                    ],
                  ),
                ],
              ),
            ),
        ],
      ),
    );
  }
}