Related
Faced a problem. My content does not fit on the page, so I added SingleChildScrollView in the TabBarLibrary. And wrapped in Expanded. As a result, I got scrolling, but also the content size greatly decreased due to Expanded, I attached a screenshot below where you can see that an empty space has appeared. How can I make the content appear on the entire page and be able to scroll?
body
Column(
children: [
const SizedBox(height: 20),
Padding(
padding: const EdgeInsets.symmetric(horizontal: 15),
child: Column(
children: [
TabBarWidget(tabController: _tabController),
],
),
),
const SizedBox(height: 20),
_divider,
TabBarLibrary(
tabController: _tabController,
size: size,
),
],
);
TabBarLibrary
return Expanded(
child: SingleChildScrollView(
child: ConstrainedBox(
constraints: BoxConstraints(maxHeight: widget.size.height * .69),
child: TabBarView(
controller: widget._tabController,
children: [
_tab1(),
Text('Tab2'),
Text('Tab3'),
],
),
),
),
);
}
tab1
return Column(
children: [
_divider,
const Padding(
padding: EdgeInsets.only(left: 24, top: 20),
child: Align(
alignment: Alignment.centerLeft,
//TODO dropdown
child: Text(
'DrowDown',
style: TextStyle(color: Colors.white),
),
),
)
...
without Expanded
Try remove ConstrainedBox, it limit your TabBarLibrary height.
Explain: You have already Expanded to determined height and a SingleChildScrollView inside wich want to fill there height, ConstrainedBox inside that limit the height, so content will not fill full the scrollview.
try wrap Expanded with SingleChildScrollView
return SingleChildScrollView(
child: Expanded(
child: ConstrainedBox(
I am making layout for flutter application
What I want to do is
-----------------------
|[i] [text] |
| |
Icon should be the left (padding 5px)
And text should be the center of screen.
At first I should use the Column
However my layout is not the same proportion
It might be simple though , how can I make it??
Stack() is one of the many options that you can use. Something like this:
Stack(
children:<Widget>[
Padding(
padding: EdgeInsets.only(left: 5),
child: Icon(Icons.info),
),
Align(
alignment: Alignment.topCenter,
child: Text("I'm on the top and centered."),
),
],
),
One way you can do this is something like this..
Widget build(BuildContext context) {
return Column(
children: [
Padding(
padding: EdgeInsets.all(5),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Icon(Icons.info),
Text('text'),
Opacity(opacity: 0, child: Icon(Icons.info)),
],
),
),
Padding(
padding: EdgeInsets.all(5),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Icon(Icons.info),
Text('second text'),
Opacity(opacity: 0, child: Icon(Icons.info)),
],
),
),
],
);
}
Result:
I might be late, but I want this answer to be there, if some one would find it better for the development purposes in future time.
We can make a reusable widget, which we can use it inside the main widget. The widget will accept text, and icon to be passed when called
// IconData is the data type for the icons
Widget myWidget(String text, IconData icon) => Row(
mainAxisSize: MainAxisSize.min,
mainAxisAlignment: MainAxisAlignment.start,
children: [
// this will be used a left-padding param
SizedBox(width: 20.0),
// using it here
Icon(icon, size: 28.0, color: Colors.greenAccent),
SizedBox(width: 5.0),
// this will take the remaining space, and then center the child
Expanded(child: Center(child: Text(text)))
]
);
To use in the main Widget, just do like this:
Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
// calling our widget here
myWidget('FirstText', Icons.alarm),
SizedBox(height: 20.0), // this is used as a top margin
myWidget('SecondText', Icons.notifications)
]
)
If you wanna check out the sources which I used, please see:
Expanded class
SizedBox class
The result you will get is this:
This was an answer I gave a while ago for this same issue, but the other situation was vertical (a Column) instead of horizontal (a Row). Just swap the Row and Columns out for a Column and Rows in this example and you'll get the idea.
My code has grey added in order to show the difference between the two approaches.
A Stack will work, but it's overkill for this, this kind of problem is part of why we have Expandeds and Flexibles. The trick is to use three Flexibles (2 Expandeds and a Spacer). Put the Spacer on top. It and the bottom Expanded must have the same flex value in order to center the middle Expanded.
import 'package:flutter/material.dart';
class CenteringOneItemWithAnotherItemInTheColumn extends StatelessWidget {
const CenteringOneItemWithAnotherItemInTheColumn({
Key key,
}) : super(
key: key,
);
/// Adjust these values as needed
final int sameFlexValueTopAndBottom = 40; // 40%
final int middleFlexValue = 20; // 20%
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Column Alignment Question'),
),
body: Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
const Spacer(),
const Text(
'Cent',
style: TextStyle(
fontSize: 64,
),
),
const Spacer(),
const Text(
'Bot',
style: TextStyle(
fontSize: 64,
),
),
],
),
Column(
children: <Widget>[
/// The key is to have the Spacer and the bottom Expanded
/// use the same value for flex. That will cause the middle
/// child of the Column to be centered vertically.
Expanded(
flex: sameFlexValueTopAndBottom,
child: Container(
width: 100,
color: Colors.grey[300],
),
),
Expanded(
flex: middleFlexValue,
child: const Align(
alignment: Alignment.center,
child: Text(
'Cent',
style: TextStyle(
fontSize: 64,
),
),
),
),
Expanded(
flex: sameFlexValueTopAndBottom,
child: Container(
color: Colors.grey[300],
child: const Align(
alignment: Alignment.bottomCenter,
child: Text(
'Bot',
style: TextStyle(
fontSize: 64,
),
),
),
),
),
],
),
],
),
);
}
}
I'm re-writing a simple app which calculates averages. However, I have a hard time with a TextField. I would like it to be exactly as on a first screenshot.
The TextField's width is stretched, I don't want that. I want it to be exactly as it is on the screenshot.
Desired look:
What I have:
Code:
import 'package:flutter/material.dart';
import 'package:easy_localization/easy_localization.dart';
class ArithmeticAverageScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('arithmetic_average_title').tr(),
),
body: Container(
padding: EdgeInsets.all(16.0),
child: Column(
children: <Widget>[
Card(
child: Container(
padding: EdgeInsets.symmetric(vertical: 20.0),
child: Column(
mainAxisSize: MainAxisSize.min,
children: <Widget>[
ListTile(
leading: Icon(Icons.help),
title: Text('arithmetic_average_help').tr(),
subtitle: Text('arithmetic_average_help_content').tr(),
)
],
),
)
),
SizedBox(height: 16.0),
Card(
child: Container(
padding: EdgeInsets.symmetric(vertical: 20.0, horizontal: 20.0),
child: Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Text('arithmetic_average_your_grades', style: Theme.of(context).textTheme.headline5).tr(),
SizedBox(height: 16.0),
Text('arithmetic_average_grades_one_at_a_time', style: Theme.of(context).textTheme.headline6,).tr(),
SizedBox(height: 16.0),
Text('arithmetic_average_grade', style: Theme.of(context).textTheme.subtitle2).tr(),
TextField()
],
),
),
)
],
),
)
);
}
}
This will help you make generic width on all devices, so here width * 0.3 means it will take 30% of the screen width
Container(
width: MediaQuery.of(context).size.width * 0.3,
child: TextField(),
)
Use Row Widget, and put Expanded Widget as child Widget and inside that put your widgets, as Expanded will take up equal space.
return Row(
children: [
Expanded(
child: TextField();
),
Expanded(
child: Button();
)
],
);
When ever you want to play with height and width you can use the widget Container.If you want to play with a property which cannot found in the widget you are using wrap it with a widget with that property will help you.
Container(
margin: const EdgeInsets.only(right: 150),
child: new TextField(
decoration: new InputDecoration(
hintText: 'Grade',
)
)
)
You can try to wrap your TextField and Button with two Flexible widgets and apply desired proportions, e.g. 1:2 which would give you following result:
Row(
children: [
Flexible(
flex: 1,
child: TextField(),
),
Flexible(
flex: 2,
child: RaisedButton(
child: Text('Hello'), onPressed: () {}),
)
],
)
],
You can also replace the first Flexible with SizedBox and set an exact value, e.g:
Row(
children: [
SizedBox(
width: 100.0,
child: TextField(),
),
Flexible(
flex: 2,
child: RaisedButton(
child: Text('Hello'), onPressed: () {}),
)
],
)
],
TextField doesn't have an intrinsic size (width) constraint so it will always try to occupy all horizontal space. Flexible allows to constraint it to desired width in a Row.
Full example on DartPad.
I have a stack widgets with two widgets inside.
One of them draws the background, the other one draws on top of that.
I want both widgets to have the same size.
I want the top widget, which is a column, to expand and fill the stack vertically to the size that is set by the background widget.
I tried setting the MainAxis mainAxisSize: MainAxisSize.max but it didn't work.
How can I make it work?
Use Positioned.fill
Stack(
children: [
Positioned.fill(
child: Column(
children: [
//...
],
),
),
//...
],
);
More info about Positioned in Flutter Widget of the Week
How does it work?
This is all about constraints. Constraints are min/max width/height values that are passed from the parent to its children. In the case of Stack. The constraints it passes to its children state that they can size themselves as small as they want, which in the case of some widgets means they will be their "natural" size. After being sized, Stack will place its children in the top left corner.
Positioned.fill gets the same constraints from Stack but passes different constraints to its child, stating the it (the child) must be of exact size (which meant to fill the Stack).
Positioned.fill() is the same as:
Positioned(
top: 0,
right: 0,
left: 0,
bottom:0,
child: //...
)
For even more examples and info: How to fill a Stack widget and why? and Understanding constraints.
You can try wrapping the Column with a positioned widget. Set top to 0 and bottom to 0. This will make the column fill the stack vertically.
sample code:
Stack(
children: <Widget>[
// Background widget rep
Container(
color: Colors.pink,
),
Positioned(
top: 0,
bottom: 0,
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text('madonna'),
Text('flutter'),
],
),
)
],
)
I think you could wrap you column in a container like this:
Container(
height: double.infinity,
width: double.infinity,
child: Column()
),
The accepted answer did not answer my issue completely. So, I put my code here in case you have a similar issue.
class NoContentView extends StatelessWidget {
const NoContentView({Key? key, required this.message}) : super(key: key);
final String message;
#override
Widget build(BuildContext context) {
return Expanded(
child: Stack(
children: [
Positioned.fill(
child: FittedBox(
child: const Image(image: AssetImage(AppImages.noReceiptsWeb), fit: BoxFit.fitWidth),
),
),
MessageView(message: message),
],
),
);
}
}
In my case, I thought that I needed to expand the container in the light blue color with an expanded widget inside the stack widget.
Problems arose, especially since I was adding the stack widget in the column widget, and the way to make the container double.infinity dimensions I definitely had a problem with the vertical axis.
In the end, I managed to show it like this photo...
Column(
children: [
//filter
Container(
color: orange,
height: 50,
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Row(
children: [
Padding(
padding: const EdgeInsets.fromLTRB(20, 0, 20, 0),
child: Text(
'All',
style: getRegular(color: white.withOpacity(.6)),
),
),
Container(
color: white.withOpacity(.6),
width: 1,
height: 50,
),
Padding(
padding: const EdgeInsets.fromLTRB(20, 0, 10, 0),
child: Text(
'Ready',
style: getRegular(color: white.withOpacity(.6)),
),
),
freeh(),
Container(
color: white.withOpacity(.6),
width: 1,
height: 50,
),
],
),
Row(
children: [
Icon(
filter,
color: white.withOpacity(.7),
size: 20,
),
Text(
'FILTER',
style: getLight(
color: white.withOpacity(.7),
),
),
freeh(),
],
),
],
),
),
Expanded(
child: Stack(
alignment: Alignment.topLeft,
children: [
Container(
color: lightBlue, //here to use map>>>>
),
Container(
height: 35,
width: 120,
margin: const EdgeInsets.all(20),
decoration: BoxDecoration(
color: primary,
borderRadius: BorderRadius.circular(20),
),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
Icon(
FontAwesomeIcons.listUl,
color: white.withOpacity(.8),
size: 20,
),
Text(
'List View',
style: getRegular(color: white.withOpacity(.8)),
)
],
),
),
],
),
)
],
),
I'm trying to bottom-center a widget at the bottom of a Column, but it keeps aligning to the left.
return new Column(
new Stack(
new Positioned(
bottom: 0.0,
new Center(
new Container(),
),
),
),
);
The existence of the Positioned forces the Container to the left, instead of centering. Removing the Positioned, however, puts the Container in the middle-center.
Align is the way to go if you have only one child.
If you have more, consider doing something like this:
return new Column(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
// Your elements here
],
);
The easiest and the correct way to do it - use Spacer()
Example:
Column(
children: [
SomeWidgetOnTheTop(),
Spacer(),
SomeCenterredBottomWidget(),
],
);
Expanded(
child: Align(
alignment: FractionalOffset.bottomCenter,
child: Padding(
padding: EdgeInsets.only(bottom: 10.0),
child: //Your widget here,
),
),
),
I have used this approach,
What i want is, A layout always in bottom but whenever Keyboard pops-up that layout also comes over it
body: Container(
color: Colors.amber,
height: double.maxFinite,
child: new Stack(
//alignment:new Alignment(x, y)
children: <Widget>[
new Positioned(
child: myWidget(context, data.iconName, Colors.red),
),
new Positioned(
child: new Align(
alignment: FractionalOffset.bottomCenter,
child: myWidget(context, data.iconName, Colors.green)
),
)
],
),
),
1) You can use an Align widget, with FractionalOffset.bottomCenter.
2) You can also set left: 0.0 and right: 0.0 in the Positioned.
Just expanding the answers:
Spacer is an option no one mentioned yet; it is used in case you prefer not to use Positioned / Align.
Align works if you want to specify the alignment of a child inside a parent. Use it anywhere but directly inside Stack
Positioned is similar to Align, but works only under Stack directly.
Design everything using Expanded() is one of the easiest way to do this
Column(
children: [
Expanded(
child: Placeholder(),
flex: 1,
),
Expanded(
child: Placeholder(),
flex: 10,
),
Expanded(
flex: 2,
child: Placeholder(),
)
],
),
If you wish to leave content as it, can wrap it with scrollable.
Useful if you have inputs in the children:
return Stack(
children: <Widget>[
Positioned(
child: SingleChildScrollView(
child: Column(
children: children
..add(Container(
height: 56, // button heigh, so could scroll underlapping area
)))),
),
Positioned(
child: Align(
alignment: Alignment.bottomCenter,
child: button,
),
)
],
);
Widget _bottom() {
return Column(
mainAxisAlignment: MainAxisAlignment.start,
children: [
Expanded(
child: Container(
color: Colors.amberAccent,
width: double.infinity,
child: SingleChildScrollView(
child: Column(
mainAxisAlignment: MainAxisAlignment.start,
crossAxisAlignment: CrossAxisAlignment.start,
children: new List<int>.generate(50, (index) => index + 1)
.map((item) {
return Text(
item.toString(),
style: TextStyle(fontSize: 20),
);
}).toList(),
),
),
),
),
Container(
color: Colors.blue,
child: Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text(
'BoTToM',
textAlign: TextAlign.center,
style: TextStyle(fontSize: 33),
),
],
),
),
],
);
}
Wrap your Container in SingleChildScrollView() widget. Then it will not come above when keyboard pops up.
In addition of Stack:
to avoid floating container on keyboard, use this
return Scaffold(
appBar: getAppBar(title),
resizeToAvoidBottomInset: false,
body: