Showing BottonNavigatorBar on All Pages in Flutter - flutter

In my app I have two pages Page1 and Page2. I also have tab bar which is displayed at the bottom of the screen. The problem is that the TabBar goes away when I use Navigator.push from one of the pages. Check out the animations below:
Here is all my code:
void main() => runApp(App());
class App extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: "Hello",
home: DefaultTabController(
length: 2,
child: Scaffold(
bottomNavigationBar: TabBar(tabs: <Widget>[
Tab(icon: Icon(Icons.directions_car)),
Tab(icon: Icon(Icons.do_not_disturb))
],
labelColor: Colors.black
)
,
body: TabBarView(children: <Widget>[
Page1(),
Page2()
])
)
)
);
}
}
class Page1 extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Page 1'),
),
body: FlatButton(
child: Text('Go to Page 2'),
onPressed: () {
Navigator.push(context, MaterialPageRoute(
builder: (context) {
return Page2();
}
));
},
color: Colors.orange
)
);
}
}
class Page2 extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Page 2'),
),
body: FlatButton(
child: Text('Go to Page 1'),
onPressed: () {
Navigator.push(context, MaterialPageRoute(
builder: (context) {
return Page1();
}
));
},
color: Colors.purple
)
);
}
}

what you want can be easily done with the help of cupertino widgets.
Example Code:
import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
void main() => runApp(MainPage());
class MainPage extends StatefulWidget {
#override
_MainPageState createState() => _MainPageState();
}
class _MainPageState extends State<MainPage> {
int _currentIndex = 0;
#override
Widget build(BuildContext context) {
return CupertinoApp(
debugShowCheckedModeBanner: false,
title: 'Demo App',
home: CupertinoTabScaffold(
tabBar: CupertinoTabBar(
items: [
BottomNavigationBarItem(
icon: Icon(Icons.event), title: Text("Tab 1")),
BottomNavigationBarItem(
icon: Icon(Icons.group), title: Text("Tab 2")),
],
currentIndex: _currentIndex,
onTap: (int) {
setState(() {
_currentIndex = int;
});
},
),
tabBuilder: (context, int) {
switch (int) {
case 0:
{
return CupertinoTabView(
builder: (context) {
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: Text('Tab 1 Content'),
),
CupertinoButton.filled(
child: Text('Goto next Page in Tab1'),
onPressed: () {
Navigator.push(context,
CupertinoPageRoute(builder: (context) {
return Body(int);
}));
})
],
),
);
},
);
}
break;
case 1:
{
return CupertinoTabView(
builder: (context) {
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: Text('Tab 2 Content'),
),
CupertinoButton.filled(
child: Text('Goto next Page in Tab2'),
onPressed: () {
Navigator.push(context,
CupertinoPageRoute(builder: (context) {
return Body(int);
}));
})
],
),
);
},
);
}
break;
}
},
),
);
}
}
class Body extends StatefulWidget {
final int index;
Body(this.index);
#override
_BodyState createState() => _BodyState();
}
class _BodyState extends State<Body> {
#override
Widget build(BuildContext context) {
return CupertinoPageScaffold(
navigationBar: CupertinoNavigationBar(
middle: Text('Page2 of Tab${widget.index}'),
),
child: Center(
child: Container(
child: Text('Page 2'),
),
));
}
}

EDIT
Sorry I misunderstood the question, this may be a duplicate of Flutter: Keep BottomNavigationBar When Push to New Screen with Navigator
Original answer
Use a single master page and replace the body dynamically with each sub page (containing their own content) :
Example :
import 'package:flutter/material.dart';
class HomePage extends StatefulWidget {
HomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_HomePageState createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
// current page index of the bottom navigation bar
int _currentIndex = 0;
// update the state of the index on tab tap
void onTabTapped(int index) {
setState(() {
_currentIndex = index;
});
}
#override
Widget build(BuildContext context) {
// list of pages of the bottom navigation bar
final List<Widget> _children = [
FirstPage(title: "My page 1"),
SecondPage(title: "My page 2"),
ThirdPage(title: "My page 3"),
];
return Scaffold(
backgroundColor: Colors.transparent,
appBar: AppBar(
title: Text(widget.title),
),
body: _children[_currentIndex],
bottomNavigationBar: BottomNavigationBar(
onTap: onTabTapped,
currentIndex: _currentIndex,
type: BottomNavigationBarType.shifting,
items: [
BottomNavigationBarItem(icon: Icon(Icons.event), title: Text("Page 1")),
BottomNavigationBarItem(icon: Icon(Icons.group), title: Text("Page 2")),
BottomNavigationBarItem(icon: Icon(Icons.camera_alt), title: Text("Page 3")),
],
),
);
}
}
Then FirstPage, SecondPage, ThirdPage can content only their own content :
import 'package:flutter/material.dart';
class FirstPage extends StatefulWidget {
FirstPage({Key key, this.title}) : super(key: key);
final String title;
#override
_FirstPageState createState() => _FirstPageState();
}
class _FirstPageState extends State<FirstPage> {
#override
Widget build(BuildContext context) {
return Scaffold(
body: // your body content
);
}
}

Pushing a route will set the Widget as the child of the MaterialApp. Every screen should contain it's own scaffold with it's own BottonNavigatorBar.

Related

Is there a way to display the BottomNavigationBar on every View?

I am trying to display the BottomNavigationBar on every View I have, it's working but this is a "dumb" way to do that...
I have a custom BottomNavigationBar which I am inserting in every View.
var selectedIndex = 0;
class CustomBottombar extends StatefulWidget {
CustomBottombar({Key key}) : super(key: key);
#override
_CustomBottombarState createState() => _CustomBottombarState();
}
class _CustomBottombarState extends State<CustomBottombar> {
List _viewList = [FirstView(), SecondView()];
#override
Widget build(BuildContext context) {
return BottomNavigationBar(
currentIndex: selectedIndex,
onTap: _onItemTapped,
items: _items,
);
}
void _onItemTapped(int index) {
setState(() {
selectedIndex = index;
Navigator.of(context).popUntil((route) => route.isFirst
);
Navigator.pushReplacement(
context,
MaterialPageRoute(builder: (context) => _viewList[index]),
);
});
}
final _items = [
BottomNavigationBarItem(
icon: Icon(
Icons.refresh,
color: Color(0xFFACACAC),
size: 35,
),
title: Text("first")),
BottomNavigationBarItem(
icon: Icon(
Icons.phone,
color: Color(0xFFACACAC),
size: 35,
),
title: Text("second"),
),
BottomNavigationBarItem(
icon: Icon(
Icons.add_shopping_cart,
color: Color(0xFFACACAC),
size: 35,
),
title: Text("thrid"),
),
];
}
in the _onItemTapped function I pop everything from the "Navigationstack" and then I am displaying the Screen that is in my Items.
in my FirstView() I have then this code
class FirstView extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: CustomAppBar(""),
bottomNavigationBar: CustomBottombar(),
endDrawer: CustomDrawer(),
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(builder: (context) => ContactView()),
);
},
child: Text('First'),
),
),
);
}
}
Now I want to move to "ContactView" which is not an Item in the BottomNavigationBar
class ContactState extends State<ContactView> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: CustomAppBar("title"),
endDrawer: CustomDrawer(),
bottomNavigationBar: CustomBottombar(),
body: SafeArea(
bottom: true,
child: SingleChildScrollView(
child: Container(child: Text("Contact"),),
)),
);
}
}
I'll also have a lot of other views which are not in the items array but I want to display the BottomNavigationBar on.
My Issue is really this function.
void _onItemTapped(int index) {
setState(() {
selectedIndex = index;
Navigator.of(context).popUntil((route) => route.isFirst
);
Navigator.pushReplacement(
context,
MaterialPageRoute(builder: (context) => _viewList[index]),
);
});
}
because here I'm deleting the navigation history to display the View which is in the Items Array.
Is there a standard way to do this, Hopefully, someone can help.
EDIT:
For clarification: I have like 10 Screens. Only 3 of those are navigatiable via BottomNavigationBar, Let's say the first 3 of those 10. now I want to Navigate to Screen4 from Screen1. The navigationbar disappears on screen4. I want Want to keep the Navigationbar on all Screens.
Edit 2
#Dhaval Kansara answer worked for me but I got a new Problem.
I have an enddrawer, before the fix it was above the BottomNavigationBar now the BottomNavigationBar is above.
but I want it like this
Use CupertinoTabBar as shown below for the static BottomNavigationBar.
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:mqttdemo/Screen2.dart';
import 'package:mqttdemo/Screen3.dart';
import 'Screen1.dart';
class Home extends StatefulWidget {
#override
_HomeState createState() => _HomeState();
}
class _HomeState extends State<Home> {
int _currentIndex;
List<Widget> _children;
#override
void initState() {
_currentIndex = 0;
_children = [
Screen1(),
Screen2(),
Screen3(),
];
super.initState();
}
#override
Widget build(BuildContext context) {
return CupertinoTabScaffold(
tabBar: CupertinoTabBar(
currentIndex: _currentIndex,
onTap: onTabTapped,
items: [
BottomNavigationBarItem(
icon: Icon(Icons.home),
title: Text("Screen 1"),
),
BottomNavigationBarItem(
icon: Icon(Icons.home),
title: Text("Screen 2"),
),
BottomNavigationBarItem(
icon: Icon(Icons.home), title: Text("Screen 3")),
],
),
tabBuilder: (BuildContext context, int index) {
return CupertinoTabView(
builder: (BuildContext context) {
return SafeArea(
top: false,
bottom: false,
child: CupertinoApp(
home: CupertinoPageScaffold(
resizeToAvoidBottomInset: false,
child: _children[_currentIndex],
),
),
);
},
);
}
);
}
void onTabTapped(int index) {
setState(() {
_currentIndex = index;
});
}
}
Navigate to screen4 from Screen3 as shown below:
class Screen3 extends StatefulWidget {
#override
_Screen3State createState() => _Screen3State();
}
class _Screen3State extends State<Screen3> {
#override
Widget build(BuildContext context) {
return Container(
color: Colors.black,
child: Center(
child: RaisedButton(
child: Text("Click me"),
onPressed: () {
Navigator.of(context, rootNavigator: false).push(MaterialPageRoute(
builder: (context) => Screen4(), maintainState: false));
},
),
),
);
}
}

Flutter: value of currentIndex property in BottomNavigationBar doesn't update when the state updates

I have a BottomNavigationBar that navigates to other pages when pressing an icon. This works fine, except the value of the currentIndex property in BottomNavigationBar doesn't update when the state updates, which means there is no change on the acual BottomNavigationBar. enter image description here
I'm using a vaiable (_selectedPage) to keep track of the selected index in the BottomNavigationBar, and the value changes when tapping an item, but it's not updating the currentIndex property when the state updates.. why is that?
import 'package:flutter/material.dart';
import 'package:independentproject/pages/home_page.dart';
import 'package:independentproject/pages/cook_recipe.dart';
class PageNavigationBar extends StatefulWidget {
#override
_PageNavigationBarState createState() => _PageNavigationBarState();
}
class _PageNavigationBarState extends State<PageNavigationBar> {
//default page showing in bottom navigation bar will be CookRecipe()
int _selectedPage = 1;
//all pages optional in bottom navigation bar
final List<Widget> _pageOptions = [
HomePage(),
CookRecipe(),
];
void onTapped(int pageTapped) {
setState(() {
//print(pageTapped);
_selectedPage = pageTapped;
Navigator.push(context, MaterialPageRoute(builder: (context) => _pageOptions[pageTapped]));
//print(_selectedPage);
});
}
#override
Widget build(BuildContext context) {
return BottomNavigationBar(
//TODO: currentIndex: doesn't update when the state updates, why?
currentIndex: _selectedPage,
//items showing in bottom navigation bar
items: [
BottomNavigationBarItem(
icon: Icon(Icons.home),
title: Text('Homepage'),
),
BottomNavigationBarItem(
icon: Icon(Icons.search),
title: Text('Search recipe'),
),
],
onTap: (int pageTapped) {
onTapped(pageTapped);
},
);
}
}
import 'package:flutter/material.dart';
import 'package:independentproject/page_navigation_bar.dart';
class HomePage extends StatefulWidget {
#override
_HomePageState createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
title: Text('Home page'),
),
body: Center(
child: Text('Home page'),
),
bottomNavigationBar: PageNavigationBar(),
),
);
}
}
import 'package:flutter/material.dart';
import 'package:independentproject/page_navigation_bar.dart';
class CookRecipe extends StatefulWidget {
#override
_CookRecipeState createState() => _CookRecipeState();
}
class _CookRecipeState extends State<CookRecipe> {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBar(
title: Text('Search recipe'),
),
body: Center(
child: Text('Search recipes'),
),
bottomNavigationBar: PageNavigationBar(),
),
);
}
}
I would advise you to create a widget that will contain the BottomNavigationBar and also PageView that would allow you to switch pages with PageController.
For example:
class _MainScreenState extends State<MainScreen> {
PageController _pageController;
int _page = 1;
Duration pageChanging = Duration(milliseconds: 300);//this is for page animation-not necessary
Curve animationCurve = Curves.linear;//this is for page animation-not necessary
_MainScreenState();
#override
void initState() {
super.initState();
_pageController = PageController(initialPage: 1);
}
Widget build(BuildContext context) {
return Scaffold(
body: PageView(
physics: BouncingScrollPhysics(),
scrollDirection: Axis.horizontal,
controller: _pageController,
onPageChanged: onPageChanged,
children: <Widget>[
//here are all the pages you need:
//CookRecipe(),
],
),
bottomNavigationBar: BottomNavigationBar(
type: BottomNavigationBarType.fixed,
items: <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(
Icons.message,
),
title: Container(height: 0.0),
),
BottomNavigationBarItem(
icon: Icon(
Icons.home,
),
title: Container(height: 0.0),
),
BottomNavigationBarItem(
icon: Icon(
Icons.person,
),
title: Container(height: 0.0),
),
],
onTap: navigationTapped,
selectedItemColor: Theme.of(context).backgroundColor,
currentIndex: _page,
),
),
);
}
void navigationTapped(int page) {
_pageController.animateToPage(page,duration: pageChanging,
curve: animationCurve,);
}
#override
void dispose() {
super.dispose();
_pageController.dispose();
}
void onPageChanged(int page) {
if (this.mounted){
setState(() {
this._page = page;
});
}}
You can also do this without the PageView,and use only the controller to switch pages.
BTW-you create new instance of the navigation bar when you load a page which is bad practice
it is because PageNavigationBar is a own class, when you call there a setstate only this class updates
take a look at the Provider
a very usefull state management Package
or you can also handle your Page, when the NavBar is your Main Page and you have only one Page
return MaterialApp(
home: Scaffold(
appBar: ownAppBar(_selectedPage),
body: _bodyOptions[_selectedPage],
bottomNavigationBar: BottomNavigationBar(
currentIndex: _selectedPage,
items: [
BottomNavigationBarItem(
icon: Icon(Icons.home),
title: Text('Homepage'),
),
BottomNavigationBarItem(
icon: Icon(Icons.search),
title: Text('Search recipe'),
),
],
onTap: (int pageTapped) {
onTapped(pageTapped);
},
)
),
);
final List<Widget> _bodyOptions = [
HomePage(),
CookRecipe(),
];
You don't need to use Navigator to change pages, I modified your code just try.
import 'package:flutter/material.dart';
main() {
runApp(MaterialApp(home: PageNavigationBar()));
}
class PageNavigationBar extends StatefulWidget {
#override
_PageNavigationBarState createState() => _PageNavigationBarState();
}
class _PageNavigationBarState extends State<PageNavigationBar> {
//default page showing in bottom navigation bar will be CookRecipe()
int _selectedPage = 1;
//all pages optional in bottom navigation bar
final List<Widget> _pageOptions = [
HomePage(),
CookRecipe(),
];
void onTapped(int pageTapped) {
setState(() {
//print(pageTapped);
_selectedPage = pageTapped;
// Navigator.push(context, MaterialPageRoute(builder: (context) => _pageOptions[pageTapped]));
//print(_selectedPage);
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: _pageOptions[_selectedPage],
bottomNavigationBar: BottomNavigationBar(
//TODO: currentIndex: doesn't update when the state updates, why?
currentIndex: _selectedPage,
//items showing in bottom navigation bar
items: [
BottomNavigationBarItem(
icon: Icon(Icons.home),
title: Text('Homepage'),
),
BottomNavigationBarItem(
icon: Icon(Icons.search),
title: Text('Search recipe'),
),
],
onTap: (int pageTapped) {
onTapped(pageTapped);
},
),
);
}
}
class CookRecipe extends StatefulWidget {
#override
_CookRecipeState createState() => _CookRecipeState();
}
class _CookRecipeState extends State<CookRecipe> {
#override
Widget build(BuildContext context) {
return Center(
child: Text('Search recipes'),
);
}
}
class HomePage extends StatefulWidget {
#override
_HomePageState createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
#override
Widget build(BuildContext context) {
return Center(
child: Text('Home page'),
);
}
}

Is it possible for me to choose to show or hide bottom navigation bar when I move to new page with navigator in flutter?

everyone.
I'm making an app which has bottom navigation bar with two items, and each item has buttons to move new pages.
Let's say each of those item is called for A and B.
A has a button for moving to new Page C. C shows today's weather. And I want to see bottom navigation bar in C as well.
B also has a button for moving to new Page D. D is login page. And I don't want to see bottom navigation bar in D.
I tried to use IndexedStack and GlobalKey, and it did work for showing bottom navigation bar in C. But I failed to hide bottom navigation bar with it in D.
I also read many articles here and there but never worked.
Can anybody help me?
class HomePage extends StatefulWidget {
#override
_HomePageState createState() => _HomePageState();
}
class _HomePageState extends State<HomePage> {
int _currentTab;
List<Widget> _tabList = [
FirstTab(),
SecondTab()
];
#override
void initState() {
super.initState();
_currentTab = 0;
}
void onItemTapped(int index) {
setState(() {
_currentTab = index;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: _tabList[_currentTab],
bottomNavigationBar: BottomNavigationBar(
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(Icons.calendar_today),
title: Text('Weather')
),
BottomNavigationBarItem(
icon: Icon(Icons.person),
title: Text('Login')
)
],
onTap: onItemTapped,
currentIndex: _currentTab,
),
);
}
}
class FirstTab extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.push(context, MaterialPageRoute(builder: (context) => WeatherPage()));
},
child: Text('To see the weather today'),
),
),
);
}
}
class SecondTab extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.push(context, MaterialPageRoute(builder: (context) => LoginPage()));
},
child: Text('To Login'),
),
),
);
}
}
class WeatherPage extends StatelessWidget { // This page needs bottom navigation bar
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: Text('Rainy'),
),
);
}
}
class LoginPage extends StatelessWidget { // There is no bottom navigation bar on this page
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: Text('Click to login'),
),
);
}
}
Edit:
Have a new bottomNavbar in the WeatherPage (first solution in comment section):
import 'package:flutter/material.dart';
class StackOverflow2 extends StatefulWidget {
#override
_StackOverflow2State createState() => _StackOverflow2State();
}
class _StackOverflow2State extends State<StackOverflow2> {
int _currentTab;
List<Widget> _tabList = [FirstTab(), SecondTab()];
#override
void initState() {
super.initState();
_currentTab = 0;
}
void onItemTapped(int index) {
setState(() {
_currentTab = index;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: _tabList[_currentTab],
bottomNavigationBar: BottomNavigationBar(
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(Icons.calendar_today), title: Text('Weather')),
BottomNavigationBarItem(
icon: Icon(Icons.person), title: Text('Login'))
],
onTap: onItemTapped,
currentIndex: _currentTab,
),
);
}
}
class WeatherPage extends StatefulWidget {
// Th
#override
_WeatherPageState createState() => _WeatherPageState();
}
class _WeatherPageState extends State<WeatherPage> {
int _currentTab;
Widget myCenter = Center(
child: Text('Rainy'),
);
List<Widget> _tabList;
#override
void initState() {
super.initState();
_tabList = [myCenter, SecondTab()];
_currentTab = 0;
}
void onItemTapped(int index) {
setState(() {
_currentTab = index;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: _tabList[_currentTab],
bottomNavigationBar: BottomNavigationBar(
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(Icons.calendar_today), title: Text('Weather')),
BottomNavigationBarItem(
icon: Icon(Icons.person), title: Text('Login'))
],
onTap: onItemTapped,
currentIndex: _currentTab,
),
);
}
}
class FirstTab extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.push(context,
MaterialPageRoute(builder: (context) => WeatherPage()));
},
child: Text('To see the weather today'),
),
),
);
}
}
class SecondTab extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.push(
context, MaterialPageRoute(builder: (context) => LoginPage()));
},
child: Text('To Login'),
),
),
);
}
}
class LoginPage extends StatelessWidget {
// There is no bottom navigation bar on this page
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: Text('Click to login'),
),
);
}
}

MaterialPageRoute goes to a new page without the appbar using it with bottomNavigationBar

I have an app with three routes and uses the bottomNavigationBar to navigate between them. In one of the routes I have a button in the page that will also navigate to one of the pages.
Heres my main page
import 'package:flutter/material.dart';
import 'page_two.dart';
import 'page_three.dart';
void main() {
return runApp(MyApp());
}
/// This Widget is the main application widget.
class MyApp extends StatelessWidget {
static const String _title = 'Flutter Code Sample';
#override
Widget build(BuildContext context) {
return MaterialApp(
title: _title,
home: MyStatefulWidget(),
);
}
}
class MyStatefulWidget extends StatefulWidget {
MyStatefulWidget({Key key}) : super(key: key);
#override
_MyStatefulWidgetState createState() => _MyStatefulWidgetState();
}
class _MyStatefulWidgetState extends State<MyStatefulWidget> {
int _selectedIndex = 0;
List<Widget> _widgetOptions = <Widget>[
Text('Main'),
PageTwo(),
PageThree(),
];
void _onItemTapped(int index) {
setState(() {
_selectedIndex = index;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('BottomNavigationBar Sample'),
),
body: Center(
child: _widgetOptions.elementAt(_selectedIndex),
),
bottomNavigationBar: BottomNavigationBar(
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(Icons.home, color: Colors.black),
title: Text('Home'),
),
BottomNavigationBarItem(
icon: Icon(Icons.business, color: Colors.black),
title: Text('Business'),
),
BottomNavigationBarItem(
icon: Icon(Icons.business, color: Colors.black),
title: Text('Business'),
),
],
currentIndex: _selectedIndex,
selectedItemColor: Colors.amber[800],
onTap: _onItemTapped,
),
);
}
}
Page Two
import 'package:flutter/material.dart';
import 'main.dart';
class PageTwo extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Container(
child: RaisedButton(
child: Text('Go page 1'),
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(builder: (context) => MyApp()),
);
},
),
);
}
}
and Page Three with a button that navigates to page two
import 'package:flutter/material.dart';
import 'page_two.dart';
class PageThree extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Container(
child: RaisedButton(
child: Text('Go page 1'),
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(builder: (context) => PageTwo()),
);
},
),
);
}
}
When I press the button on Page Three, it will go to Page Two without the AppBar and the BottomNavigationBar
Use GlobalKey and In PageTwo Widget call MyStatefulWidgetState's _onItemTapped function
You can see working demo and full code below
code snippet
final scakey = new GlobalKey<_MyStatefulWidgetState>();
...
child: Text('Go page 2'),
onPressed: () {
scakey.currentState._onItemTapped(1);
full code
import 'package:flutter/material.dart';
void main() {
return runApp(MyApp());
}
final scakey = new GlobalKey<_MyStatefulWidgetState>();
/// This Widget is the main application widget.
class MyApp extends StatelessWidget {
static const String _title = 'Flutter Code Sample';
#override
Widget build(BuildContext context) {
return MaterialApp(
title: _title,
home: MyStatefulWidget(key: scakey),
);
}
}
class MyStatefulWidget extends StatefulWidget {
MyStatefulWidget({Key key}) : super(key: key);
#override
_MyStatefulWidgetState createState() => _MyStatefulWidgetState();
}
class _MyStatefulWidgetState extends State<MyStatefulWidget> {
int _selectedIndex = 0;
final myKey = new GlobalKey<_MyStatefulWidgetState>();
List<Widget> _widgetOptions = <Widget>[
Text('Main'),
PageTwo(),
PageThree(),
];
void _onItemTapped(int index) {
setState(() {
_selectedIndex = index;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
key: myKey,
appBar: AppBar(
title: const Text('BottomNavigationBar Sample'),
),
body: Center(
child: _widgetOptions.elementAt(_selectedIndex),
),
bottomNavigationBar: BottomNavigationBar(
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(Icons.home, color: Colors.black),
title: Text('Home'),
),
BottomNavigationBarItem(
icon: Icon(Icons.business, color: Colors.black),
title: Text('Business'),
),
BottomNavigationBarItem(
icon: Icon(Icons.business, color: Colors.black),
title: Text('Business'),
),
],
currentIndex: _selectedIndex,
selectedItemColor: Colors.amber[800],
onTap: _onItemTapped,
),
);
}
}
class PageTwo extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Container(
child: RaisedButton(
child: Text('Go page 1'),
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(builder: (context) => MyApp()),
);
},
),
);
}
}
class PageThree extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Container(
child: RaisedButton(
child: Text('Go page 2'),
onPressed: () {
scakey.currentState._onItemTapped(1);
/*Navigator.push(
context,
MaterialPageRoute(builder: (context) => PageTwo()),
);*/
},
),
);
}
}
When using navigation bar to navigate between pages, you are tapping on BottomNavigationBarItem to change the index by calling setState() and as the result, build method is triggered with a new _selectedIndex and that index is used to render your appropriate widget.
_widgetOptions.elementAt(_selectedIndex)
Navigator.push on the other hand is just pushing a new route on top of the navigation stack. You are not getting an AppBar or BottomNavigationBar since you don't have them on PageTwo. What I would recommend you is to create a callback function in PageTwo and call that function on button tap. You can now use that callback in MyStatefulWidget to change the index with setState. Here is an example
Declare a final like below in your pages.
final void Function(int index) pageChanged;
In the onTap event of your button, call this function.
widget.pageChanged(1); // PageTwo
In MyStatefulWidget, when you are creating pages, pass the function.
PageTwo(pageChanged:(index){
setState(){_selectedIndex = index;}
});

Alert box with multi select chip in flutter

I have a multiselect chip in my app , but when since the data in the AlertDialog depends dynamically, it will be 1 or 100, so I have added SingleChildScrollView over the alert Dialog to give scrolling if there are more entries , but when I added SingleChildScrollView my alert box goes to top of the screen like this, I want it to align in center,
If I removed the SingleChildScrollView then It will come like this which I wanted. but If there are lot of entries I cant select because It cant cover the entire data?
Is there any way where I can align it to center of screen with scroll enabled?
Thanks
showDialog(
context: context,
builder: (BuildContext context) {
return SingleChildScrollView(
child: AlertDialog(
title: Text("choose items"),
content: MultiSelectChip(
reportList,
onSelectionChanged: (selectedList) {
setState(() {
listSelectedItem = selectedList;
});
},
),
actions: <Widget>[
FlatButton(
child: Text("CANCEL"),
onPressed: () {
setState(() {
dropdownSelected = null;
listSelectedItem.clear();
});
Navigator.of(context).pop();
}),
In AlertDialog's content use Container and constraints, and in Container's child wrap SingleChildScrollView then wrap MultiSelectChip
code snippet
return AlertDialog(
title: Text("Report Video"),
content: Container(
constraints: BoxConstraints(
maxHeight: 100.0,
),
child: SingleChildScrollView(
child: MultiSelectChip(
reportList,
onSelectionChanged: (selectedList) {
setState(() {
selectedReportList = selectedList;
});
},
),
),
),
actions: <Widget>[
FlatButton(
child: Text("Report"),
onPressed: () => Navigator.of(context).pop(),
)
],
);
})
full code
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
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> reportList = [
"Not relevant",
"Illegal",
"Spam",
"Offensive",
"Uncivil",
"a123",
"b234",
"c2314",
"aaaa",
"a",
"1Not relevant",
"2Illegal",
"3Spam",
"4Offensive",
"5Uncivil",
"6a123",
"7b234",
"8c2314",
"9aaaa",
"0a",
"Not relevant",
"Illegal",
"Spam",
"Offensive",
"Uncivil",
"a123",
"b234",
"c2314",
"aaaa",
"a",
"1Not relevant",
"2Illegal",
"3Spam",
"4Offensive",
"5Uncivil",
"6a123",
"7b234",
"8c2314",
"9aaaa",
"0a",
];
List<String> selectedReportList = List();
_showReportDialog() {
showDialog(
context: context,
builder: (BuildContext context) {
//Here we will build the content of the dialog
return AlertDialog(
title: Text("Report Video"),
content: Container(
constraints: BoxConstraints(
maxHeight: 100.0,
),
child: SingleChildScrollView(
child: MultiSelectChip(
reportList,
onSelectionChanged: (selectedList) {
setState(() {
selectedReportList = selectedList;
});
},
),
),
),
actions: <Widget>[
FlatButton(
child: Text("Report"),
onPressed: () => Navigator.of(context).pop(),
)
],
);
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
RaisedButton(
child: Text("Report"),
onPressed: () => _showReportDialog(),
),
Text(selectedReportList.join(" , ")),
],
),
),
);
}
}
class MultiSelectChip extends StatefulWidget {
final List<String> reportList;
final Function(List<String>) onSelectionChanged;
MultiSelectChip(this.reportList, {this.onSelectionChanged});
#override
_MultiSelectChipState createState() => _MultiSelectChipState();
}
class _MultiSelectChipState extends State<MultiSelectChip> {
// String selectedChoice = "";
List<String> selectedChoices = List();
_buildChoiceList() {
List<Widget> choices = List();
widget.reportList.forEach((item) {
choices.add(Container(
padding: const EdgeInsets.all(2.0),
child: ChoiceChip(
label: Text(item),
selected: selectedChoices.contains(item),
onSelected: (selected) {
setState(() {
selectedChoices.contains(item)
? selectedChoices.remove(item)
: selectedChoices.add(item);
widget.onSelectionChanged(selectedChoices);
});
},
),
));
});
return choices;
}
#override
Widget build(BuildContext context) {
return Wrap(
children: _buildChoiceList(),
);
}
}