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Is it possible we can add onPressed action on the logo and start another activity?
I am creating a simple flutter app where I have used AppBar and in leading icon I have used a custom logo. I am not sure how to perform onPressed method so that it starts another activity. Anyone please help me here. Below is my app bar code.
class SecondScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
leading: Padding(
padding: const EdgeInsets.all(8.0),
child: Image.asset(
"assets/images/logo.png",
),
),
title: Text('Safe Outs Business'),
),
body: Center(
child: Text('Admin HomePage'),
),
);
}
}
Click here to see a sample Image of the layout I am trying to build in flutter
You can embed your logo inside a GestureDetector:
return Scaffold(
appBar: AppBar(
leading: Padding(
padding: const EdgeInsets.all(8.0),
child: GestureDetector(
onTap: () => print('TAPPED!'),
child: Image.asset(
"assets/images/logo.png",
),
),
),
title: Text('Safe Outs Business'),
),
body: Center(
child: Text('Admin HomePage'),
),
);
I want to open a drawer after pushing on the custom button in BottomMenu I have trouble with Scaffold.of(context).openDrawer(), it doesn't work. My BottomMenu is a separate widget class. As I understand, it doesn't work because it's a separate context. How can I get the right context? Or perhaps someone knows another solution.
Here my code reproducer:
import 'package:flutter/material.dart';
void main() => runApp(MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
home: MyHomePage(title: 'Flutter Drawer'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
bottomNavigationBar: BottomMenu(),
endDrawer: SizedBox(
width: double.infinity,
child: Drawer(
elevation: 16,
child: Container(
color: Colors.black,
child: ListView(
padding: EdgeInsets.zero,
children: <Widget>[
ListTile(
title: Text('Some context here',
style: TextStyle(color: Colors.white))),
ListTile(
title: Text('Some context here',
style: TextStyle(color: Colors.white))),
],
),
),
),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'Call Drawer form menu reproducer',
)
],
),
),
);
}
}
class BottomMenu extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Padding(
padding: const EdgeInsets.symmetric(horizontal: 15),
child: Wrap(
alignment: WrapAlignment.center,
children: <Widget>[
Divider(color: Colors.black, height: 1),
Padding(
padding: const EdgeInsets.symmetric(vertical: 2),
child: Row(
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
InkWell(
borderRadius: new BorderRadius.circular(20.0),
customBorder: Border.all(color: Colors.black),
child: Container(
padding: EdgeInsets.only(
left: 3, right: 6, bottom: 15, top: 11),
child: Row(
children: <Widget>[
Icon(Icons.menu),
Text('Show menu', style: TextStyle(fontSize: 15, fontWeight: FontWeight.bold)),
],
),
),
onTap: () {
Scaffold.of(context).openDrawer();
},
),
],
),
),
],
),
);
}
}
In my case, this worked.
return Scaffold(
key: _scaffoldKey,
endDrawerEnableOpenDragGesture: false, // This!
appBar: AppBar(
iconTheme: IconThemeData(color: Colors.white),
leading: IconButton(
icon: Icon(Icons.menu, size: 36),
onPressed: () => _scaffoldKey.currentState.openDrawer(), // And this!
),
),
drawer: DrawerHome(),
....
and _scaffoldKey must be initialized as,
final GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey<ScaffoldState>();
under the class.
The problem is that you specified endDrawer on Scaffold yet you're calling Scaffold.of(context).openDrawer().
openDrawer() documentation states:
If the scaffold has a non-null Scaffold.drawer, this function will cause the drawer to begin its entrance animation.
Since your drawer is null, nothing happens.
In contrast, openEndDrawer() informs us:
If the scaffold has a non-null Scaffold.endDrawer, this function will cause the end side drawer to begin its entrance animation.
Since your endDrawer is not null you should use openEndDrawer() method. Alternatively, if you don't care which side the drawer slides in from, you can use drawer instead of endDrawer when building Scaffold.
My problem solved that instead of
Scaffold.of(context).openEndDrawer()
I give key to Scaffold and then I call by state like below
_scaffoldkey.currentState.openEndDrawer()
It solved my problem I hope It also works for you
Scaffold.of(context).openEndDrawer()
The Problem
This issue can occur when you do not use the correct BuildContext when calling Scaffold.of(context).openDrawer() (or openEndDrawer()).
Easiest Solution
Simply wrap whatever calls openDrawer() (or openEndDrawer()) with a Builder widget. This will give it a working context.
Minimal Working Example
// your build method
#override
Widget build(BuildContext context) {
return Scaffold(
floatingActionButton: Builder(builder: (context) { // this uses the new context to open the drawer properly provided by the Builder
return FloatingActionButton(onPressed: (() => Scaffold.of(context).openDrawer()));
}),
drawer: const Drawer(
child: Text("MY DRAWER"),
),
);
}
Similar problem here. Clicked on button and nothing happened. The problem is I was using the context of the widget that instantiated Scaffold. Not the context of a child of Scaffold.
Here is how I solved it:
// body: Column(
// children: <Widget>[
// Row(
// children: <Widget>[
// IconButton(
// icon: Icon(Icons.filter_list),
// onPressed: () => Scaffold.of(context).openEndDrawer(), (wrong context)
// ),
// ],
// ),
// ],
// )
To:
body: Builder(
builder: (context) => Column(
children: <Widget>[
Row(
children: <Widget>[
IconButton(
icon: Icon(Icons.filter_list),
onPressed: () => Scaffold.of(context).openEndDrawer(),
),
],
),
],
)),
),
Assign Drawer to drawer property in scaffold. Wrap your specific Widget/Button(where you want to open drawer on its click method) with Builder. Use below method on click property:
enter image description here
Scaffold.of(context).openDrawer();
If you have the appbar widget with an action button to launch the drawer and the drawer is never pushed please remember that you need to define after appbar: ... the endDrawer: YOURAppDrawerWIDGET(), or else using the Scaffold.of(context).openEndDrawer() will not work.
Scaffold(
appBar: AppBar(title: Text(_title)),
endDrawer: AppDrawer(), // <-- this is required or else it will not know what is opening
body: SingleChildScrollView(
///...
Working on an App that will require multiple screens. The below right now shows only two icons, more later, and i need them the be able to go the a corresponding screen when pressed. Everything works but the onPressed function. The error I get is
The named parameter "onPressed" is not defined
Do I have the onPressed function in the wrong spot? I have tried moving it between other functions but I get the same error.
Any help is appreciated
main.dart
import 'package:flutter/material.dart';
import './food_screen.dart';
void main(List<String> args) {
runApp(new MaterialApp(
home : MyApp(),
));
}
class MyApp extends StatefulWidget {
#override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: new AppBar(
title :Text('Main Title'),
backgroundColor: Colors.blue,
),
backgroundColor: Colors.blue[100],
body: Container(
padding: EdgeInsets.all(30.0),
child: GridView.count(
crossAxisCount: 2,
children: <Widget>[
Card(
margin: EdgeInsets.all(8.0),
child: InkWell(
onTap: (){
Navigator.push(context,
MaterialPageRoute(builder: (context)=>FoodScreen())
);
},
splashColor: Colors.blue,
child: Center(
child: Column(
children: <Widget>[
Icon(Icons.fastfood, size: 70.0),
Text("FOOD", style: new TextStyle(fontSize: 28.0))
]
)
),
),
),
Card(
margin: EdgeInsets.all(8.0),
child: InkWell(
onTap: (){},
splashColor: Colors.blue,
child: Center(
child: Column(
children: <Widget>[
Icon(Icons.directions_car, size: 70.0),
Text("VEHILCES", style: new TextStyle(fontSize: 28.0))
],
),
),
),
),
]
)
)
);
}
}
food_screen.dart
import 'package:flutter/material.dart';
import './main.dart';
class FoodScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Second Screen"),
),
);
}
}
Card doesn't support onPressed property, you already have InkWell which has onTap, you can put onPressed method action inside it.
onTap: () {
Navigator.push(context,
MaterialPageRoute(builder: (context)=>FoodScreen())
);
}
Card doesn't have any property of onpressed()
you can add a floating button and Route it to the the second page i.e food_screen.dart
https://api.flutter.dev/flutter/material/Card-class.html
if you want to add a tap on Card Widget just wrap the card with GestureDetector.
I have this problem with actions of AlertDialog
AlertDialog(
title: ...,
content: ...,
actions: <Widget>[
FlatButton(onPressed: ...,
child: Text(btn_download)),
FlatButton(onPressed: ...,
child: Text('btn_select')),
FlatButton(onPressed: ...,
child: Text(btn_qr)),
FlatButton(onPressed: ...,
child: Text(btn_cancel)),
],
);
When I show this dialog I get this:
I tried to use Wrap or other scrolling and multi-child widets, but nothing helps.
Found the same issue here, but no answer yet
Does anybody knows how this can be fixed?
I don't have access to AndroidStudio to validate my hypothesis, but I'd try something like this:
AlertDialog(
title: ...,
content: ...,
actions: <Widget>[
new Container (
child: new Column (
children: <Widget>[
FlatButton(onPressed: ...,
child: Text(btn_download)),
FlatButton(onPressed: ...,
child: Text('btn_select'))
),
new Container (
child: new Column (
children: <Widget>[
FlatButton(onPressed: ...,
child: Text(btn_gr)),
FlatButton(onPressed: ...,
child: Text('btn_cancel'))
),
),
],
);
Edit: this code works, but you have to use a width-constrained Container, even though it seems that a 75% screen width is somewhat of a sweet spot, since it works both in portrait and landscape mode.
import 'package:flutter/material.dart';
import 'dart:async';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Flutter Demo',
theme: new ThemeData(
primarySwatch: Colors.blue,
),
home: new MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counter = 0;
Future<Null> _neverSatisfied() async {
double c_width = MediaQuery.of(context).size.width*0.75;
return showDialog<Null>(
context: context,
barrierDismissible: false, // user must tap button!
builder: (BuildContext context) {
return new AlertDialog(
title: new Text('Rewind and remember'),
content: new SingleChildScrollView(
child: new ListBody(
children: <Widget>[
new Text('You will never be satisfied.'),
new Text('You\’re like me. I’m never satisfied.'),
],
),
),
actions: <Widget>[
new Container(
width: c_width,
child: new Wrap(
spacing: 4.0,
runSpacing: 4.0,
children: <Widget>[
new FlatButton(
child: new Text('The Lamb'),
onPressed: () {
Navigator.of(context).pop();
},
),
new FlatButton(
child: new Text('Lies Down'),
onPressed: () {
Navigator.of(context).pop();
},
),
new FlatButton(
child: new Text('On'),
onPressed: () {
Navigator.of(context).pop();
},
),
new FlatButton(
child: new Text('Broadway'),
onPressed: () {
Navigator.of(context).pop();
},
),
],
)
)
],
);
},
);
}
void _doNeverSatisfied() {
_neverSatisfied()
.then( (Null) {
print("Satisfied, at last. ");
});
}
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text(widget.title),
),
body: new Center(
child: new Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
new Text(
'You have pushed the button this many times:',
),
new Text(
'$_counter',
style: Theme.of(context).textTheme.display1,
),
],
),
),
floatingActionButton: new FloatingActionButton(
onPressed: _doNeverSatisfied,
tooltip: 'Call dialog',
child: new Icon(Icons.add),
), // This trailing comma makes auto-formatting nicer for build methods.
);
}
}
The ButtonBar is not made for so many buttons.
Place your buttons in a Wrap widget or a Column.
I'm trying to center the title text in an app bar that has both a leading and trailing actions.
#override
Widget build(BuildContext context) {
final menuButton = new PopupMenuButton<int>(
onSelected: (int i) {},
itemBuilder: (BuildContext ctx) {},
child: new Icon(
Icons.dashboard,
),
);
return new Scaffold(
appBar: new AppBar(
// Here we take the value from the MyHomePage object that
// was created by the App.build method, and use it to set
// our appbar title.
title: new Text(widget.title, textAlign: TextAlign.center),
leading: new IconButton(
icon: new Icon(Icons.accessibility),
onPressed: () {},
),
actions: [
menuButton,
],
),
body: new Center(
child: new Text(
'Button tapped $_counter time${ _counter == 1 ? '' : 's' }.',
),
),
floatingActionButton: new FloatingActionButton(
onPressed: _incrementCounter,
tooltip: 'Increment',
child: new Icon(Icons.add),
), // This trailing comma makes auto-formatting nicer for build methods.
);
}
This works well except the title is aligned on the left as is shown in this picture:
As I try to include the title in the center, it appears that it's too much to the left:
#override
Widget build(BuildContext context) {
final menuButton = new PopupMenuButton<int>(
onSelected: (int i) {},
itemBuilder: (BuildContext ctx) {},
child: new Icon(
Icons.dashboard,
),
);
return new Scaffold(
appBar: new AppBar(
// Here we take the value from the MyHomePage object that
// was created by the App.build method, and use it to set
// our appbar title.
title: new Center(child: new Text(widget.title, textAlign: TextAlign.center)),
leading: new IconButton(
icon: new Icon(Icons.accessibility),
onPressed: () {},
),
actions: [
menuButton,
],
),
body: new Center(
child: new Text(
'Button tapped $_counter time${ _counter == 1 ? '' : 's' }.',
),
),
floatingActionButton: new FloatingActionButton(
onPressed: _incrementCounter,
tooltip: 'Increment',
child: new Icon(Icons.add),
), // This trailing comma makes auto-formatting nicer for build methods.
);
}
I would love a solution to get the title text centered perfectly between the 2 icons.
Centering the title is the default on iOS. On Android, the AppBar's title defaults to left-aligned, but you can override it by passing centerTitle: true as an argument to the AppBar constructor.
Example:
AppBar(
centerTitle: true, // this is all you need
...
)
I had the same problem and it finally worked when I added the
mainAxisSize: MainAxisSize.min to my Row() widget:
return new Scaffold(
appBar: new AppBar(
// Here we take the value from the MyHomePage object that
// was created by the App.build method, and use it to set
// our appbar title.
title: Row(
mainAxisAlignment: MainAxisAlignment.center,
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Text(
widget.title,
),
],
),
leading: new IconButton(
icon: new Icon(Icons.accessibility),
onPressed: () {},
),
actions: [
menuButton,
],
),
);
}
In my case I wanted to have a logo / image centered instead of a text. In this case, centerTitle is not enough (not sure why, I have an svg file, maybe that's the reason... ), so for example, this:
appBar: AppBar(centerTitle: true, title: AppImages.logoSvg)
will not really center the image (plus the image can be too big, etc.). What works well for me is a code like this:
appBar: AppBar(centerTitle: true,
title: ConstrainedBox(
constraints: BoxConstraints(maxHeight: 35, maxWidth: 200),
child: AppImages.logoSvg)),
You can just use the centerTitle property in the appBar section to center your title
using:
centerTitle: true
Here is how I make centerTitle on my appbar:
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: new AppBar(
centerTitle: true ,
title: new Text("Login"),
),
body: new Container(
padding: EdgeInsets.all(18.0),
key: formkey,
child: ListView(
children: buildInputs() + buildSubmitButton(),
),
)
);
}
Here is a different approach if you want to create a custom app bar title. For example you want an image and a text at the center of app bar then add
appBar: AppBar(
title: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Icon(
Icons.your_app_icon,
color: Colors.green[500],
),
Container(
padding: const EdgeInsets.all(8.0), child: Text('YourAppTitle'))
],
),
)
Here we have created a Row with MainAxisAlignment.center to center the children. Then we have added two children - An Icon and a Container with text. I wrapped Text widget in the Container to add the necessary padding.
You can center the title of an appBar by using centerTitle parameter.
centerTitle is Boolean Datatype, and default value is False.
centerTitle : true
Example :
import 'package:flutter/material.dart';
void main() {
runApp(
MaterialApp(
home: Scaffold(
appBar: AppBar(
title: Text('App Title'),
backgroundColor: Colors.red,
centerTitle: true,
),
),
),
);
}
Yeah but in my case i used centertitle as well as axis alignment then it made it centre , if i am using only onw of it then it is is not making it centre , here is how i am doing it :
import 'package:flutter/material.dart';
import 'package:infintywalls/widgets/widget.dart';
class Home extends StatefulWidget {
#override
_HomeState createState() => _HomeState();
}
class _HomeState extends State<Home> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Row(
mainAxisAlignment: MainAxisAlignment.center,
mainAxisSize: MainAxisSize.min,
children: <Widget>[
appName(),
],
),
elevation: 0.0,
centerTitle: true,
),
);
}
}
and yeah btw appName() is my custom widget not a default builtin one.
home this is helpful to you
thanks
appBar has its own bool condition for title center show or not,
so,
if you set true,
appBar: AppBar(
title: Text(
"header Text",
style: TextStyle(color: Colors.black),
),
centerTitle: true,
),
then it will be centre,other then its default left align (in android)
ios set center(in default).
Try the following code:
AppBar(
centerTitle: true,
…
),
It can be done by using Center class.
appBar: AppBar(
title: const Center(
child: Text("I Am Rich"),
),
),
After trying many solutions this helped me centerTitle: true
adding sample code in addition to #Collin Jackson answer
Example
in build(BuildContext context)
do this
appBar: AppBar(
// Here we take the value from the MyHomePage object that was created by
// the App.build method, and use it to set our appbar title.
title: Text(widget.title),centerTitle: true
),
appbar:AppBar(
centerTitle: true,
title:Text("HELLO")
)
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Title'),
actions: <Widget> [
IconButton(icon: const Icon(Icons.file_upload), onPressed: _pressed),
],
leading: IconButton(icon: const Icon(Icons.list), onPressed: _pressed),
centerTitle: true,
)
body: Text("Content"),
);
}
This can help in making Appbar Title Text in Center.
You can choose to add your desired Styles using Style or comment it if not needed.
appBar: AppBar(
title: const Center(
child: Text(
"App Title",
style: TextStyle( color: Colors.white,fontSize: 20),
),
),
),
On App Display:
It my case this code works:-
appBar: AppBar(
centerTitle: true,
elevation: 2,
title: Center(
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Container(
child: Text(" TINKLE"),
)
],
),
),
),
Hope this was helpful.
Use Center object
appBar: AppBar(
title: Center(
child: const Text('Title Centered')
)
)