Flutter layout without AppBar - flutter

I need a layout without an appbar, so the most obvious approach is to just leave out the appbar tag on the Scaffold but if I do that the content goes underneath the status bar like this:
As you can see my container which is colored in blue starts right from underneath the status bar which shouldn't be the case, so I had to manually set the margin of the container which is not so nice, this is the results:
I have this feeling that devices might have status bars with varying heights so setting my top margin to fixed size might not render properly on other devices. Is there a way for flutter to position my content automatically below the status like it positions the AppBar nicely below the status bar.
Here is my scaffold code:
return new Scaffold(
body: new Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
new HeaderLayout(),
],
),
);
This is my header container:
class HeaderLayout extends StatelessWidget{
#override
Widget build(BuildContext context) {
return new Container(
color: Colors.blue,
margin: const EdgeInsets.only(top: 30.0),
child: new SizedBox(
height: 80.0,
child: new Center(
child: new Text(
"Recommended Courses",
style: new TextStyle(color: Colors.white),
),
),
)
);
}
}

Wrap your Column with SafeArea
body: new SafeArea(
child: new Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
new HeaderLayout(),
],
)
) ,
SafeArea is a widget that insets its child by sufficient padding to avoid intrusions by the operating system.
For example, this will indent the child by enough to avoid the status bar at the top of the screen.

You can get the OS padding with MediaQuery.
You'd have to replace your
margin: const EdgeInsets.only(top: 30.0),
by
margin: MediaQuery.of(context).padding,
Another solution is to wrap your content inside a SafeArea. Which basically does the same thing.

void main() {
SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle(
systemNavigationBarColor: Colors.blue, // navigation bar color
statusBarColor: Colors.pink, // status bar color
));
}

Related

can't figure out where pixels are overlflow even thought I use MediaQuery height

As a demo, I have taken two container inside Column and I have used MediaQuery height for both container and deducting size of appear..eventhought it is showing 24 pixel overflow...and if I wrap column with SingleChildScrollView..it scrolls which should be not scrolled as both container's height sum is 1.
here is my demo code
import 'package:flutter/material.dart';
class HomeScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
final appbar=AppBar();
return Scaffold(
appBar: appbar,
body: SingleChildScrollView(
child: Column(
children: [
Container(
height: (MediaQuery.of(context).size.height-appbar.preferredSize.height)*0.40 ,
color: Colors.green,
),
Container(
height: (MediaQuery.of(context).size.height-appbar.preferredSize.height)*0.60 ,
color: Colors.red,
),
],
),
)
);
}
}
Column has property 'mainAxisSize', setting that to MainAxisSize.min will solve the problem.
Column(
mainAxisSize: MainAxisSize.min,
children: [
Container(
height: (MediaQuery.of(context).size.height-appbar.preferredSize.height)*0.40 ,
color: Colors.green,
),
In this case Column just stretches to infinity as ScrollView above allows it.
I got my answer from stack overflows history ....
here what I missed to deduct status bar height
height: (MediaQuery.of(context).size.height-appbar.preferredSize.height-MediaQuery.of(context).viewPadding.top)*0.60 ,

Flutter strange padding on top of status bar

I want to remove the strange padding on top of the status bar. I am simply using an image and want to put that image on top of the screen that is behind the status bar. So that the status bar icons should be overlayed on the image.
Simply using Scaffold as a parent widget and then simple an Image. Screen shot is here!
The icons are not properly overlapping the image, and there is a white padding on top head!
I am using an Android Emulator right now, can somebody please figure out what I am missing.
class PreSignInScreen extends StatelessWidget {
final PreSignInController controller = Get.put(PreSignInController());
#override
Widget build(BuildContext context) {
return Scaffold(
body: SingleChildScrollView(
child: Column(
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: [
const SizedBox(
height: 10,
),
getRedCarBox(context),
]
);
)
}
Thanks & Advance
Try below code, I have tried
- Scaffold
- Column
- Container
- Image
Your Widget:
Scaffold(
body: Column(
children: [
Container(
width: double.infinity,
height: 300,
decoration: BoxDecoration(
image: DecorationImage(
fit: BoxFit.fill,
image: NetworkImage(
'https://cdn.pixabay.com/photo/2022/03/27/11/23/cat-7094808__340.jpg',
),
),
),
),
//Add your other widgets here
],
),
),
Or Using SafeArea, top property false
SafeArea(
top: false,
child: Container(),
),
Result Screen->
Try this:
#override
Widget build(BuildContext context) {
return WillPopScope(
onWillPop: () async {
return false;
},
child: Scaffold(
body: SafeArea(
top: false,
bottom: false,
child: _buildBody(),
),
),
);
}
Scaffold(
body: SafeArea(
top: false,
bottom: false,
child: _yourBody(),
),
Why to use SafeArea :
SafeArea class Null safety. A widget that insets its child by sufficient padding to avoid intrusions by the operating system. For example, this will indent the child by enough to avoid the status bar at the top of the screen.

Flutter: Transparent clipped AppBar

I have a waved app bar that looks like this:
As you can see the clipped area is not transparent but rather has the (black) canvas color and is blocking some ListView entries.
The code for the app bar looks something like this:
class MainAppBar extends StatelessWidget implements PreferredSizeWidget {
...
#override
Widget build(BuildContext context) {
return PreferredSize(
child: ClipPath(
clipper: WaveClip(),
child: Container(
color: getAppBarColor(),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
...
],
),
),
),
preferredSize: const Size.fromHeight(kToolbarHeight + 60));
}
}
As one can see I am using a ClipPath with a custom clipper to clip a Container. How do I clip it in a transparent manner?
try this:
Scaffold(
extendBodyBehindAppBar: true,
this will make items behind appbar visible

How to change color of Flutter ButtonBar in a Scaffold?

How can I change the color of a ButtonBar in Flutter? There isn't a color in ButtonBarTheme as far as I can tell. I am trying to do something like this:
return Scaffold(
backgroundColor: Colors.red,
body: Center(child: Text('foo')),
// Somehow get the color of these buttons different to backgroundColor
persistentFooterButtons: _buildTextButtons(),
);
The best I can think of at the moment is to somehow reimplement the persistent footer buttons myself, but that is ugly. The problem seems to be that the Scaffold backgroundColor property is used in multiple places, yet is defined in a single widget. This means I can't wrap it in a Theme and override it piecemeal either, as far as I can tell.
Oh, I might have found an answer. I had been using both the bottomNavigationBar and the persistentFooterButtons. persistentFooterButtons are wrapped in a ButtonBar, which appears to limit your styling options.
bottomNavigationBar is a single widget, though, so you can fiddle with it. I switched to just build my own persistentFooterButtons after all.
(I had to edit this from my app, so it might not be copy/paste ready.)
Widget _buildNavigationBar(BuildContext ctx, Color barColor) {
List<Widget> actions = [
// We need the first element to be big, to push everything to the right.
Expanded(
child: Container(),
),
];
actions.addAll(_buildTextButtons(ctx));
Widget actionContainer = ColoredBox(
color: barColor,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Row(
mainAxisSize: MainAxisSize.min,
mainAxisAlignment: MainAxisAlignment.end,
children: actions,
),
),
);
return Column(
mainAxisSize: MainAxisSize.min,
children: [
actionContainer,
// I use this to make space for ads.
Container(
color: barColor,
height: 50,
),
],
);
}
return Scaffold(
backgroundColor: Colors.red,
body: Center(child: Text('foo')),
// removed this persistentFooterButtons: _buildTextButtons(),
// and replaced with this:
bottomNavigationBar: _buildNavigationBar(ctx),
);
you can also wrap that ButtonBar into Container and After that, you can make any type of changes to that ButtonBar, like coloring etc

Color of a widget inside a Stack is always slightly transparent

I display a custom-made bottom app bar in a Stack because of keyboard padding reasons. The custom widget is fully opaque as it should be until it's a child of a Stack in which case, the content behind it starts to be visible since the color's opacity somehow changes.
As you can see, it's only the "main" color that's transparent. Icons remain opaque.
This is the build method of my custom BottomBar widget which is then just regularly put into a Stack. I have tried using a Material and even a simple Container in place of the BottomAppBar widget but the results are the same.
#override
Widget build(BuildContext context) {
return BottomAppBar(
color: Colors.blue.withOpacity(1),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
IconButton(
icon: Icon(MdiIcons.plusBoxOutline),
onPressed: () {},
),
Text('Edited 11:57'),
IconButton(
icon: Icon(MdiIcons.dotsVertical),
onPressed: () {},
),
],
),
);
}
Can you interact with the BottomAppBar ? It looks like an order problem. Try to put the BottomAppBar as last in the Stack children.
Note that BottomAppBar doesn't have a constant size, if you did not add it to Scaffold bottomNavigationBar named parameter has a size if this is not null. Below is peace of code in Scaffold dart file:
double bottomNavigationBarTop;
if (hasChild(_ScaffoldSlot.bottomNavigationBar)) {
final double bottomNavigationBarHeight = layoutChild(_ScaffoldSlot.bottomNavigationBar, fullWidthConstraints).height;
bottomWidgetsHeight += bottomNavigationBarHeight;
bottomNavigationBarTop = math.max(0.0, bottom - bottomWidgetsHeight);
positionChild(_ScaffoldSlot.bottomNavigationBar, Offset(0.0, bottomNavigationBarTop));
}
You can even develop your own Widget without BottomAppBar but if you want things like centerDocked and things like circular notched, you will have to do more stuff (anyway you have flexibility to custom design the way you want).
Here is a simple example to do that(one way to do that):
import 'package:flutter/material.dart';
class CustomBottomBar extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
body: Stack(
children: <Widget>[
Container(
margin: EdgeInsets.only(bottom: 50),
color: Colors.greenAccent, // if you want this color under bottom bar add the margin to list view
child: ListView.builder(
itemCount: 100,
itemBuilder: (_, int index) => Text("Text $index"),
),
),
Positioned(
bottom: 0,
child: Container(
color: Colors.amber.withOpacity(.5),
width: MediaQuery.of(context).size.width,
height: 50,
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: List.generate(4, (int index) => Text("Text $index")), // you can make these clickable by wrapping with InkWell or any gesture widget
),
),
),
],
),
);
}
}