Flutter background of unsafe area in SafeArea widget. - dart

When I provide the SafeArea to a Widget, then it gets some margin from the notches and home button (horizontal line in iPhone X +). How can I change the background of the unsafe area ? (The margin portion)?

Wrap your SafeArea into a widget that adds a background:
Container(
color: Colors.red,
child: SafeArea(...),
),

Another way to do it.
import 'package:flutter/services.dart';
Scaffold(
body: AnnotatedRegion<SystemUiOverlayStyle>(
value: SystemUiOverlayStyle.light.copyWith(
statusBarColor: Theme.of(context).primaryColor
),
child: SafeArea(
child: Container(...),
),
),
)

Following on from Rémi Rousselet's answer...
In my case, I created a new widget called ColoredSafeArea:
import 'package:flutter/material.dart';
class ColoredSafeArea extends StatelessWidget {
final Widget child;
final Color? color;
const ColoredSafeArea({
Key? key,
required this.child,
this.color,
}) : super(key: key);
#override
Widget build(BuildContext context) {
return Container(
color: color ?? Theme.of(context).appBarTheme.backgroundColor,
child: SafeArea(
child: Container(
color: Theme.of(context).colorScheme.background,
child: child,
),
),
);
}
}
And use this in place of SafeArea in my Scaffold. I have it set up to use the current AppBar colour from my theme, by default. But you can use whatever works for you, of course.
Basically, this widget will change the SafeArea colour without affecting your app background colour, due to the Container within, which takes the background colour from the current theme's colorScheme. The advantage of this is that the background colour will work with any dark or light themes you have set up.

This is probably the easiest way to accomplish this:
const Scaffold(
backgroundColor: Colors.white,
body: SafeArea(
child: Text(
"White scaffold background that also applies to status bar",
style: TextStyle(fontSize: 20),
),
),
);
Basically use SafeArea as a child of Scaffold and set the scaffold's background color to whatever you want or use ThemeData to set it globally using the scaffoldBackgroundColor prop

I have combined both the above answers to achieve
the system theme set (dark/light)
the color/gradient of unsafe area
The code I've used is
var brightness = SchedulerBinding.instance.window.platformBrightness;
bool isDarkModeOn = brightness == Brightness.dark;
Widget build(BuildContext context) {
return Scaffold(
body: AnnotatedRegion<SystemUiOverlayStyle>(
value: isDarkModeOn
? SystemUiOverlayStyle.dark.copyWith(
statusBarColor: Theme.of(context).primaryColor,
)
: SystemUiOverlayStyle.light.copyWith(
statusBarColor: Theme.of(context).primaryColor,
),
child: Container(
decoration: getScreenGradient(),
child: SafeArea(
child: Container(
child: Center(
child: Stack(
children: [
getBackgroundImage(),
getBody(),
],
),
),
),
),
),
),
);
}

Related

Animated widget pushes other widgets

I have an animated widget (image) located top of the page and under the widget there should be a text.
I use size transition widget and it pushes all the widgets under itself. I don't want my animation to push any other widgets. Everything should stay where they are. I expect something like this:
layout
Widget _animation() {
Image img= Image.asset(
'assets/images/myImg.jpg',
);
_controller.forward(from: 0);
return SizeTransition(
child: img,
sizeFactor: CurvedAnimation(
curve: Curves.fastOutSlowIn,
parent: _controller,
),
);
}
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Column(
crossAxisAlignment: CrossAxisAlignment.center,
children: <Widget>[
_animation(),
Text(
"My Text",
style: TextStyle(color: Colors.black87, fontSize: 30),
),
],
),
),
);
}
Actually the SizeTransition won't work if you have given it's parent a fixed size. I am showing you how to do it using Stack.
#override
Widget build(BuildContext context) {
return SafeArea(
child: Scaffold(
body: Stack(
children: <Widget>[
Positioned(left: 0, child: _animation()),
Positioned(top: 100, child: Text("This is your text",)),
],
),
),
);
}
Try using a Stack and Positioned element, so that your element will clip above the elements that you're "moving". Think of it as a position: absolute in html.
Try using SlideTransition instead of SizeTransition because you want to move your image from top to real position.
Widget _animation() {
Image img= Image.asset(
'assets/images/myImg.jpg',
);
_controller.forward(from: 0);
return SlideTransition(
child: img,
position: Tween<Offset>(begin: Offset(0.0, -1.0), end: Offset.zero)
.animate(_controller),
);
}
More info here:
https://docs.flutter.io/flutter/widgets/SlideTransition-class.html

Flutter - Is there a way to use just IconButton (without creating an app bar) to open the drawer?

I'm trying to use the IconButton that can open the drawer on my app page, so when I tap the icon button, I expect to see the drawer. I've been looking up a way to do so online, but seemed like there're only two solutions: I can either use the appbar to put the IconButton in, or I can try the floating action button. But they're not what I'm looking for, I want just the IconButton to open the drawer. Is it possible do it?
Yes, you can easily open the drawer through IconButton without using appBar.
You need to use Key like I had used _scaffoldKey and use _scaffoldKey.currentState.openDrawer() method to open the drawer in IconButton widget.
class HomeState extends StatelessWidget {
final GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey<ScaffoldState>();
#override
Widget build(BuildContext context) {
return Scaffold(
key: _scaffoldKey,
drawer: Drawer(
child: ListView(
children: <Widget>[
ListTile(
title: Text("Ttem 1"),
trailing: Icon(Icons.arrow_forward),
),
ListTile(
title: Text("Item 2"),
trailing: Icon(Icons.arrow_forward),
),
],
),
),
body: ListView(
children:[
Container(
margin: EdgeInsets.only(left: 15.0,top:100.0),
child: IconButton(
icon: Icon(Icons.menu),
onPressed: () {
_scaffoldKey.currentState.openDrawer();
},
),
),
]
),
);}
}

Flutter: change theme brightess on part of screen?

How can I make a theme get a Dark brightess on only a part of the screen? The brightness doest not work on the text.
#override
Widget build(BuildContext context) {
return Center(
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Theme(
data: ThemeData(brightness: Brightness.light),
child: Container(
child: Text("Bright Text"),
),
),
Theme(
data: ThemeData(brightness: Brightness.dark),
child: Container(
child: Text("Dark Text"),
),
),
],
),
);
}
It seems that this solution actually works, the reason you can't observe it in your original example is because the default text color in both color modes is the same — black (at least that's what I've got experimenting with it).
If you change your example to use a widget that uses a color that actually changes, you can clearly see it's working:
#override
Widget build(BuildContext context) {
return Center(
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
Theme(
data: ThemeData(brightness: Brightness.light),
child: Container(
child: Icon(Icons.audiotrack), // always renders a black icon
),
Theme(
data: ThemeData(brightness: Brightness.dark),
child: Container(
child: Icon(Icons.audiotrack), // always renders a white icon
),
),
],
),
);
}
Sometimes you need to get the brightness of the current context to do some intricate configuration; the common way to do this: MediaQuery.of(context).platformBrightness will always give you the current color mode of the device/platform.
If you want to get the brightness that was "overridden" by the method above, you need to use Theme.of(context).brightness instead.

Flutter: Setting the height of the AppBar

How can I simply set the height of the AppBar in Flutter?
The title of the bar should be staying centered vertically (in that AppBar).
You can use PreferredSize:
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Example',
home: Scaffold(
appBar: PreferredSize(
preferredSize: Size.fromHeight(50.0), // here the desired height
child: AppBar(
// ...
)
),
body: // ...
)
);
}
}
Use toolbarHeight:
There's no longer a need to use PreferredSize. Use toolbarHeight with flexibleSpace.
AppBar(
toolbarHeight: 120, // Set this height
flexibleSpace: Container(
color: Colors.orange,
child: Column(
children: [
Text('1'),
Text('2'),
Text('3'),
Text('4'),
],
),
),
)
You can use PreferredSize and flexibleSpace for it:
appBar: PreferredSize(
preferredSize: Size.fromHeight(100.0),
child: AppBar(
automaticallyImplyLeading: false, // hides leading widget
flexibleSpace: SomeWidget(),
)
),
This way you can keep the elevation of AppBar for keeping its shadow visible and have custom height, which is what I was just looking for. You do have to set the spacing in SomeWidget, though.
The easiest way is to use toolbarHeight property in your AppBar
Example :
AppBar(
title: Text('Flutter is great'),
toolbarHeight: 100,
),
You can add flexibleSpace property in your appBar for more flexibility
Output:
For more controls , Use the PreferedSize widget to create your own appBar
Example :
appBar: PreferredSize(
preferredSize: Size(100, 80), //width and height
// The size the AppBar would prefer if there were no other constraints.
child: SafeArea(
child: Container(
height: 100,
color: Colors.red,
child: Center(child: Text('Fluter is great')),
),
),
),
Don't forget to use a SafeArea widget if you don't have a safeArea
Output :
At the time of writing this, I was not aware of PreferredSize. Cinn's answer is better to achieve this.
You can create your own custom widget with a custom height:
import "package:flutter/material.dart";
class Page extends StatelessWidget {
#override
Widget build(BuildContext context) {
return new Column(children : <Widget>[new CustomAppBar("Custom App Bar"), new Container()],);
}
}
class CustomAppBar extends StatelessWidget {
final String title;
final double barHeight = 50.0; // change this for different heights
CustomAppBar(this.title);
#override
Widget build(BuildContext context) {
final double statusbarHeight = MediaQuery
.of(context)
.padding
.top;
return new Container(
padding: new EdgeInsets.only(top: statusbarHeight),
height: statusbarHeight + barHeight,
child: new Center(
child: new Text(
title,
style: new TextStyle(fontSize: 20.0, fontWeight: FontWeight.bold),
),
),
);
}
}
In addition to #Cinn's answer, you can define a class like this
class MyAppBar extends AppBar with PreferredSizeWidget {
#override
get preferredSize => Size.fromHeight(50);
MyAppBar({Key key, Widget title}) : super(
key: key,
title: title,
// maybe other AppBar properties
);
}
or this way
class MyAppBar extends PreferredSize {
MyAppBar({Key key, Widget title}) : super(
key: key,
preferredSize: Size.fromHeight(50),
child: AppBar(
title: title,
// maybe other AppBar properties
),
);
}
and then use it instead of standard one
You can simply use toolbarHeight, as follows:
appBar: AppBar(
toolbarHeight: 70.0, // add this line
centerTitle: true, // add this line
title: Text('your title'),
),
but if you have any actions the code above doesn't work as you want
you can use this code
AppBar(
centerTitle: true,
title: Padding(
padding: const EdgeInsets.all(16.0),
child: Stack(
alignment: Alignment.center,
children: [
Row(
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text('Chats', style: TextStyle(color:Colors.black),),
Icon(Icons.add, color: Colors.black,),
],
),
Align(
alignment: Alignment.centerRight,
child: Icon(Icons.add, color: Colors.black,),
),
],
),
),
)
Cinn's answer is great, but there's one thing wrong with it.
The PreferredSize widget will start immediately at the top of the screen, without accounting for the status bar, so some of its height will be shadowed by the status bar's height. This also accounts for the side notches.
The solution: Wrap the preferredSize's child with a SafeArea
appBar: PreferredSize(
//Here is the preferred height.
preferredSize: Size.fromHeight(50.0),
child: SafeArea(
child: AppBar(
flexibleSpace: ...
),
),
),
If you don't wanna use the flexibleSpace property, then there's no need for all that, because the other properties of the AppBar will account for the status bar automatically.
simply use toolbar height ...
AppBar(
title: Text("NASHIR'S APP"),
toolbarHeight: 100,
),
You can use the toolbarHeight property of Appbar, it does exactly what you want.
class AppBarWidget extends StatelessWidget with PreferredSizeWidget {
final String title;
const AppBarWidget({Key? key, required this.title}) : super(key: key);
#override`enter code here`
Widget build(BuildContext context) {
return AppBar(
title: Text(title),
centerTitle: true,
elevation: 0,
actions: [
Padding(
padding: const EdgeInsets.only(right: 10),
child: IconButton(
icon: const FaIcon(FontAwesomeIcons.language),
onPressed: () {},
),
),
],
);
}
#override
Size get preferredSize => const Size.fromHeight(40);// change
}
You can use PreferredSize, by this use can set multiple children widget inside their
appBar: PreferredSize(
preferredSize: Size(MediaQuery.of(context).size.width, 75),
child: Column(children: [
AppBar(
centerTitle: true,
toolbarHeight: 74,
backgroundColor: Colors.white,
elevation: 0,
title: Column(
children: [
Text(
viewModel.headingText,
style: sfDisplay16500Text,
),
SizedBox(
height: 8.0,
),
Text(
viewModel.url.toString(),
style: sfDisplay10400LightBlackText,
maxLines: 1,
overflow: TextOverflow.ellipsis,
)
],
),
),
]),
),
or just directly use toolbarHeight property for only increase hight of appBar.
appBar: AppBar(
title: Text('AppBar Texr'),
toolbarHeight: 200.0, // double
),
Extend AppBar class and override preferredSize
class AppBarCustom extends AppBar {
#override
Size get preferredSize => Size.fromHeight(100);
}
then use it as you would use AppBar class
class MyHomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
appBar: AppBarCustom(),
body:
),
);
}
}
This is simplest and easiest way to change appbar height without changing original theme.
class AppBarSectionView extends StatefulWidget implements PreferredSizeWidget {
const AppBarSectionView({Key? key}) : super(key: key);
#override
_AppBarSectionViewState createState() => _AppBarSectionViewState();
#override
Size get preferredSize => const Size.fromHeight(kToolbarHeight + 20);
}
class _AppBarSectionViewState extends State<AppBarSectionView> {
#override
Widget build(BuildContext context) {
return AppBar(
toolbarHeight: widget.preferredSize.height ,
backgroundColor: Colors.red,
leading: const Icon(Icons.arrow_back_ios_rounded),
title: const Text("This Is Title"),
);
}
}
If you are in Visual Code, Ctrl + Click on AppBar function.
Widget demoPage() {
AppBar appBar = AppBar(
title: Text('Demo'),
);
return Scaffold(
appBar: appBar,
body: /*
page body
*/,
);
}
And edit this piece.
app_bar.dart will open and you can find
preferredSize = new Size.fromHeight(kToolbarHeight + (bottom?.preferredSize?.height ?? 0.0)),
Difference of height!

Flutter - FloatingActionButton in the center

Is it possible to make the FloatingActionButton in the centre instead of the right side?
import 'package:flutter/material.dart';
import 'number.dart';
import 'keyboard.dart';
class ContaPage extends StatelessWidget {
#override
Widget build(BuildContext context) => new Scaffold(
body: new Column(
children: <Widget>[
new Number(),
new Keyboard(),
],
),
floatingActionButton: new FloatingActionButton(
elevation: 0.0,
child: new Icon(Icons.check),
backgroundColor: new Color(0xFFE57373),
onPressed: (){}
)
);
}
I don't know if this was added since this question was first answered, but there's now floatingActionButtonLocation property on the Scaffold class.
It would work like this in your original question:
class ContaPage extends StatelessWidget {
#override
Widget build(BuildContext context) => new Scaffold(
// ...
floatingActionButton: new FloatingActionButton(
// ...FloatingActionButton properties...
),
// Here's the new attribute:
floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
);
}
Also see the documentation:
Scaffold class (search floatingActionButtonLocation): https://docs.flutter.dev/flutter/material/Scaffold-class.html
...and the FloatingActionButtonLocation class: https://docs.flutter.dev/flutter/material/FloatingActionButtonLocation-class.html
With the new flutter API you do that very easily just change the floatingActionButtonLocation property in the Scaffold to
FloatingActionButtonLocation.centerFloat
Example :
return new Scaffold(
floatingActionButton: new FloatingActionButton(
child: const Icon(Icons.add),
),
floatingActionButtonLocation:
FloatingActionButtonLocation.centerFloat,
bottomNavigationBar: new BottomAppBar(
color: Colors.white,
child: new Row(...),
),
);
Use the Property floatingActionButtonLocation of scaffold class.
floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
Full Example:
import 'package:flutter/material.dart';
final Color darkBlue = Color.fromARGB(255, 18, 32, 47);
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData.dark().copyWith(scaffoldBackgroundColor: darkBlue),
debugShowCheckedModeBanner: false,
home: HomePage()
);
}
}
class HomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(),
body: Container(child: Center(child: Text('Hello World')),),
floatingActionButton: FloatingActionButton(
onPressed: () {},
child: Icon(Icons.camera, color: Colors.white, size: 29,),
backgroundColor: Colors.black,
tooltip: 'Capture Picture',
elevation: 5,
splashColor: Colors.grey,
),
floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
);
}
}
floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
Use this property with floatingActionButtonLocation property in Scaffold.
FloatingActionButton Flutter - More Details
Try wrapping it in a Center widget or use a crossAxisAlignment of CrossAxisAlignment.center on your Column.
You should pick one part of your Column to be wrapped in a Flexible that will collapse to avoid overflow, or replace some or all of it with a ListView so users can scroll to see the parts that are hidden.
You can use Container and Align widgets as below:
#override
Widget build(BuildContext context) {
return new Scaffold(
body: Center(
),
floatingActionButton: Container(
padding: EdgeInsets.only(bottom: 100.0),
child: Align(
alignment: Alignment.bottomCenter,
child: FloatingActionButton.extended(
onPressed: _getPhoneAuthResult,
icon: Icon(Icons.phone_android),
label: Text("Authenticate using Phone"),
),
),
),
floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
);
}
Align(
alignment: Alignment.center,
child: Container(
child: FloatingActionButton(
hoverColor: Colors.black,
elevation: 10,
onPressed: () {},
backgroundColor: Colors.pink,
child: Icon(Icons.add,),
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.all(Radius.circular(20.0))),
),
),
),
Here I used "Align" widget to make the FloatingActionButton center. You can see it here.
after end of the floating action button widget, you can Use floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
For Example
import 'dart:io';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
#override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
File _image;
#override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData.dark(),
title: "Camera App",
home: Scaffold(
appBar: AppBar(
title: Text("Camera App"),
),
body: Center(
child: Center(
child: _image == null
? Text('No image selected.')
: Image.file(_image,
alignment: Alignment.topLeft,
),
),
),
floatingActionButton: FloatingActionButton(
elevation: 50,
hoverColor: Colors.red,
autofocus: true,
onPressed: () {
imagepicker();
},
child: Icon(Icons.camera_alt),
tooltip: 'Pick Image',
),
floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
),
);
}
Future imagepicker() async {
var image = await ImagePicker.pickImage(source: ImageSource.gallery);
setState(() {
_image = image;
});
}
}
The above examples are great, but if you want to have full control over the exact location of the floating action button, you should wrap your FloatingActionButton widget with Align widget and use Alignment(x axis, y axis) to set the exact location.
Align(
alignment: Alignment(0.0, 0.8),
//control the location by changing the numbers here to anything between 1 and -1
child: FloatingActionButton()
)
By changing the logic to use crossAxisAlignment, the mainAxisAlignment and the Flexible the FloatingActionButton were centered at the bottom of the screen
import 'package:flutter/material.dart';
import 'number.dart';
import 'keyboard.dart';
class ContaPage extends StatelessWidget {
#override
Widget build(BuildContext context) => new Scaffold(
body: new Column(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
new Number(),
new Keyboard(),
new Flexible(
child: new Container(
padding: new EdgeInsets.only(bottom: 16.0),
child: new FloatingActionButton(
elevation: 0.0,
child: new Icon(Icons.check),
backgroundColor: new Color(0xFFE57373),
onPressed: (){}
)
)
)
],
),
);
}
For more freedom of alignment and more than 2 FAB use Stack
Stack(
children: <Widget>[
Center(
child: Center(
child: _image == null
? Text('No image selected.')
: Image.file(_image,
alignment: Alignment.topLeft,
),
),
),
Align(
alignment: Alignment.centerLeft,
child: new FloatingActionButton(
child: const Icon(Icons.skip_previous),
onPressed: () {
}),
),
Align(
alignment: Alignment.centerRight,
child: new FloatingActionButton(
child: const Icon(Icons.skip_next),
onPressed: () {
}),
),
],
)
I modified the code, now the button is in the bottom center but I do not know if it will always stay in the bottom, regardless of the size of the screen.
import 'package:flutter/material.dart';
import 'number.dart';
import 'keyboard.dart';
class ContaPage extends StatelessWidget {
#override
Widget build(BuildContext context) => new Scaffold(
body: new Column(
children: <Widget>[
new Number(),
new Keyboard(),
new Stack(
alignment: new FractionalOffset(0.5, 1.0),
children: <Widget>[
new FloatingActionButton(
elevation: 0.0,
child: new Icon(Icons.check),
backgroundColor: new Color(0xFFE57373),
onPressed: (){}
)
],
)
],
),
);
}
Since Scaffold.floatingActionButton just asks for a Widget, you can wrap your FloatingActionButton with the standard classes for more control if the Scaffold.floatingActionButtonLocation property isn't enough (which already gives you many standard placements, that can also play nicely with your appBar or bottomNavigationBar).
Container is a classic component, but a little overkill given that it combines a variety of widgets.
As others mentioned, Align is handy when you want to position relative to the Align widget itself (which if unconstrained fills to its parent). It can take a variety of preset Alignment constants, or use the Alignment constructor to specify your own relative position, e.g. Alignment(0.0, 0.0) represents the center of the rectangle, (1,1) the bottom right corner, and (-1,-1) the upper left. However, the parent of your FAB is influenced by the Scaffold's floatingActionButtonLocation:, so one way to help take it into account is by setting it to FloatingActionButtonLocation.centerDocked, which when used with Align lets you think about positioning relative to the screen's center.
But maybe you like the basic positioning provided by floatingActionButtonLocation, but just want to shift the FAB by a known number of logical pixels, e.g. to compensate for other widgets on the screen. In that case wrapping in a Padding with the appropriate EdgeInsets should work fine.
Depending on your design simply you can use persistentFooterButtons which accepts a list of widgets as children.
just like here for an example:
persistentFooterButtons: [
new Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
child: Align(
alignment: Alignment.center,
child: FloatingActionButton(
onPressed: (){
Navigator.push(context, MaterialPageRoute(builder: (context) => InstallationPage()),);
},
child: new Icon(Icons.add, color: SysColors.ICON_COLOR, size: 34.w,),
),
),
],
)
],

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