Related
like the title says is there a way to place a widget on bottom of screen in expanded
Expanded -> SingleChildScrollView() -> column(children: [ -> Container() -> ElevatedButton() ])
i want the ElevatedButton to be placed on the bottom of screen also i don't want to place it away of the Expanded widget, is there a way to do that ?
Expanded(
child: Column(
children: [
Container(),
//use Spacer(),
Spacer(),
ElevatedButton()
],
),
)
try use spacer inside column
SingleChildScrollView(
child: Container(
height: MediaQuery.of(context).size.height - APPBAR_SIZE,
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Container(child: CHILD),
ElevatedButton(),
],
),
),
)
UPDATE:
Column(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
Container(
height: MediaQuery.of(context).size.height - APPBAR_SIZE - ElevatedButtonHeight,
child: SingleChildScrollView(
child: Container(child: CHILD),
),
),
ElevatedButton(),
],
),
I started to develop in Flutter recently and I am having difficulties in centralizing a Widget completely in the available space of View.
This is how it looks:
And here's what I want to achieve:
And here's my code:
LayoutBuilder(builder:
(BuildContext context, BoxConstraints viewportConstraints) {
return SingleChildScrollView(
child: ConstrainedBox(
constraints: BoxConstraints(
minHeight: viewportConstraints.maxHeight,
),
child: Column(
mainAxisSize: MainAxisSize.min,
children: [
Column(children: [
NavHeader("Deposit"),
BalanceHeader(widget.usd),
]),
Column(
mainAxisSize: MainAxisSize.min,
children: [
Text(
"How much do you want deposit?",
style:(
...
),
),
Container(
alignment: Alignment.center,
width: width * 0.4,
margin: EdgeInsets.only(top: 10),
child: Row(
...
),
),
],
),
],
),
),
);
}),
bottomNavigationBar: BottomAppBar(
...
),
),
);
}
By using MainAxisSize.min The height of the Column will be according to the combined height of its children and incoming height from the parent will be ignored. That means your column height has shrinked to its children.
There is you can use MainAxisSize.max instead of MainAxisSize.min to max height of column. And also you have to use mainAxisAlignment: MainAxisAlignment.center for aligning childrens to center of column.
Your Second Column
Column(
mainAxisSize: MainAxisSize.min,
children: [
Text(
"How much do you want deposit?",
style:(
...
),
),
Container(
alignment: Alignment.center,
width: width * 0.4,
margin: EdgeInsets.only(top: 10),
child: Row(
...
),
),
],
),
Edited Column
Column(
mainAxisSize: MainAxisSize.max,
mainAxisAlignment: MainAxisAlignment.center
children: [
Text(
"How much do you want deposit?",
style:(
...
),
),
Container(
alignment: Alignment.center,
width: width * 0.4,
margin: EdgeInsets.only(top: 10),
child: Row(
...
),
),
],
),
Well, there is a widget for that!
As for most things in flutter just Wrap the Widgets you want centered inside a Center widget and you should achieve what you want.
Column(
mainAxisAlignment: MainAxisAlignment.center,
children ... Your code
)
You could also wrap your widget with the Column widget and it will work only for the X coordinates.
(It has already been stated but poorly)
I need to create the following:
I could do it with code:
Row(
children: <Widget>[
Container(
width: 30
),
Column(
children: <Widget>[
Text("label"),
Container(
width: screenSize.width - 30, // <- this is problem
child: Row(
children: <Widget>[
Expanded( child: TextField() ),
Expanded( child: TextField() ),
],
),
),
],
),
],
);
Is it possible to do it in a different way, namely the line width: screenSize.width - 30?
You can use crossAxisAlignment inside Column widget and make it Stretch to get all remaining width in screen
Row(
children: <Widget>[
Container(
width: 30
),
Column(
crossAxisAlignment: CrossAxisAlignment.stretch, // <- Add this
children: <Widget>[
Text("label"),
Container(
child: Row(
children: <Widget>[
Expanded( child: TextField() ),
Expanded( child: TextField() ),
],
),
),
],
),],);
[Please read official flutter documentation of Column widget]
Column Widget
CrossAxisAlignment
Solution
Row(
children: <Widget>[
Container(
color: Colors.red,
width: 50,
),
Expanded(
child: Column(
children: <Widget>[
Text("label"),
Expanded(
child: Row(
children: <Widget>[
Expanded(
child: TextField()
),
Expanded(
child: TextField()
),
],
),
),
],
),
),
],
);
Explanation
It is about where you place Expanded instances.
You have a row, which can fill its parent if it included an Expanded child. So we defined the size of one of its children (Container), and the other is simply Expanded. The same goes for the Column child ..
Maybe starting with a simpler example makes it easier to understand. Please refer to this useful answer.
Output
P.S. Welcome to StackOverFlow, Dmitry!
In my layout I have two Widgets in a row, one text and the an icon.
As shown below, assume that * refers to the icon, and using "-" to represent the row:
----------------------------
Text *
----------------------------
How do I make my text centered in the entire row, and the icon to the right end ?
The main thing you need to notice is that if you don't want to use Stack you should provide same width-consuming widgets both on left and right.
I would do this with either Expanded and Padding
Row(
children: <Widget>[
Expanded(
child: Padding(
padding: const EdgeInsets.only(left: 32.0),
child: Text(
"Text",
textAlign: TextAlign.center,
),
),
),
Icon(Icons.add, size: 32.0,)
],
)
or with Row's mainAxisAlignment and a SizedBox
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
const SizedBox(width: 32.0),
Text("Text"),
Icon(Icons.add, size: 32.0)
],
)
or with Expanded and a SizedBox on the left instead of the padding :). The padding or extra container on the left is so that the textAlign will truly center the text in the row taking into account the space taken up by the Icon.
Simply use Expanded and Spacer widgets on left/right side and put your widget inside the Expanded:
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Spacer(),
Text('Text'),
Expanded(
child: Text('*'),
),
),
],
),
Result:
1. Using Row (not very flexible though)
Row(
children: <Widget>[
Expanded(child: Center(child: Text('Center'))),
Text("#"),
],
)
2. Using Stack (flexible)
IntrinsicHeight(
child: Stack(
children: [
Align(child: Text('Center')),
Positioned(right: 0, child: Text('#')),
],
),
)
I found it necessary to use a Stack to get Text to be truly centered:
Column(
mainAxisSize: MainAxisSize.min,
crossAxisAlignment: CrossAxisAlignment.stretch,
children: [
Stack(
alignment: Alignment.center,
children: [
Align(
alignment: Alignment.center,
child: Text('Text'),
),
Align(
alignment: Alignment.centerRight,
child: Text('*'),
)
],
),
],
);
For flexibility reasons I recommend to use Expanded widgets:
Row(
children: [
Expanded(flex: 1, child: Container()),
Expanded(
flex: 8,
child: Text('Your Text',
textAlign: TextAlign.center,
),
),
Expanded(flex: 1, child: IconButton(...))
],
)
For my case, I solved my centering problem by adjusting the flex property of the Spacer widget -
Row(children: [
Spacer(flex: 3),//3 was for my case, It might be changed for your widgets
Text('Center'),
Spacer(flex: 1),//1 was also for my case, It might be changed on for your widgets
Text("*")]);
Add another icon in the start and set the opacity to zero.
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
CloseButton(
onPressed: () => Navigator.of(context).pop(),
),
Text('text',),
Opacity(
opacity: 0,
child: Icon(Icons.close),
),
],
)
This worked for me without Stack. But it is the other way around. "Text" goes to left "*" goes to center:
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Expanded(
child: Text("text",
style: Theme.of(context).textTheme.caption),
),
Text("*"),
Spacer(),
],
)
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: