----------------------------
# Text *
----------------------------
Text in the center
# left of Text and it is variable length
* at the far right and it is variable length
I've tried using spaceBetween but it doesn't seem to work because components width are different
Try this:
Expanded for # in Container with alignment centerRight, Text, Expanded for * in Container with alignment centerRight in Row.
You can use the Expanded widget to achieve this, Using Expanded Widget you can control the width or height of each child in Row or Column Widget
In Your case Use Row Widget with Expanded for each child
For Example:
Row(
children: [
Expanded(
flex: 2,
child: Text("#")
),
Expanded(
flex: 2,
child: Text("Text")
),
Expanded(
flex: 1,
child: Text("*")
),
]
)
Adjust the value of flex value according to your needs and align text to left. right, or center
For more info check out this link and for video: https://api.flutter.dev/flutter/widgets/Expanded-class.html
Related
I have a text that can vary in height, followed by a PopupMenuButton. I want the text to be center-aligned on the vertical axis (so that there isn't a weird white space when there's only 1 ligne of text) but the PopupMenuButton to stay in the top right corner, no matter the height of the text. Thus using crossAxisAlignement doesn't work here since all widgets are affected. Using an Align widget on the text or PopupMenuButton doesn't work and textAlign doesn't either It seems any solution must be implemented on the Row level and not in its children, which makes sense.
For now I'm using a Row to contain these 2 widgets, but I'm not so sure it is what I need if I want the behaviour mentionned before. Is there a solution for the Row, or another widget I can use for this ?
Here is the code as it stands. Thanks.
Row(
children: [
Expanded(
child: RichText(
text: TextSpan(), // bunch of text in there
)
)
),
SizedBox( // To box in the 3 dots icon (material design forces 48px otherwise)
height: 24,
width: 24,
child: PopupMenuButton(
padding: EdgeInsets.all(0),
onSelected: menuSelect,
itemBuilder: (BuildContext context) {
return [
PopupMenuItem(value: 0, child: Text('Read', textAlign: TextAlign.center,),),
PopupMenuItem(value: 1, child: Text('Delete', textAlign: TextAlign.center,),)
];
},
),
)
],
)
Here's a way to do it :
Wrap your SizedBox with an Align(alignment: Alignment.topRight)
Wrap your Row with an IntrinsicHeight so that the cross-axis
doesn't stretch
Alternatively, you might want to look into the Stack widget if you're not familiar with it.
How do you guys solve the following Flutter layout??
I have a screen, where I have to show, as described in the picture: a logo + 3 TextFormFields + 2 buttons + a Container.
Problems:
I need to put all the widgets inside a Column and, the Column inside a SingleChildScrollView so that, when the keyboard pops up, it does not cover the TextFields.
The last widget, the Container, shall take all the remaining screen space on the bottom, but NOT taking more than the screen size. For that, My idea was to use the Expanded widget, so that the Container can expand to the bottom of the screen, but that gives an error:
The following assertion was thrown during performLayout(): RenderFlex children have non-zero flex but incoming height constraints are unbounded.
So I guess my question, in short is, how do I prevent the keyboard to cover the TextFields, while at the same time I force the Container to take all the remaining space on the bottom.
That was my attempt:
SingleChildScrollView(
child: Column(
children: [
Image.asset("assets/images/appLogo.png"),
TextFormField(),
TextFormField(),
TextFormField(),
Row(children: [TextButton(), TextButton()]),
Expanded(child: Container())
],
));
Expanded doesn't know how much size to take. Also the other children don't know their exact size.
Wrap your Image inside a container and give height & width to it. also try wrapping all textfields inside a column or container each.
SingleChildScrollView(
child: Column(
children: [
Container(
width: MediaQuery.of(context).Size.width * 0.4,
height: MediaQuery.of(context).Size.height * 0.2,
child: Image.asset("assets/images/appLogo.png"),
),
Column(
children: [
TextFormField(),
TextFormField(),
TextFormField(),]
)
Row(children: [TextButton(), TextButton()]),
Expanded(child: Container())
],
));
I hope this will work for you.
I am struggling with making the column scrollable:
Container(
height: double.infinity,
width: double.infinity,
color: Colors.blue,
child: Column(
children: [
Expanded(flex: 2, child...),
Expanded(flex: 5, child...)
]
)
)
I tried wrapping all the widget inside a single child scroll view, I tried a list view and I tried combing layout builder but nothing works
When you use expanded you should have a limited space (height in column and width in row), in your case your height will fit the space in screen.
If you change the column to the scrollview even change it directly to the ListView or swap it with the SingleChildScrollView, you will have unlimited space and you can't use expanded widget, because it wants to fill all possible space, and it is unlimited in scrollview
I have two widgets in a row. The first widget is a black line with width 5.0, the second widget is a text widget whose size may vary according to the content. I want the first container to have the same height as of the second widget
One way is to make both widget child of an IntrinsicHeight widget and then declare the height of the first container as double.infinity. This should solve your problem. Example code is given below:
IntrinsicHeight(
child: Row(
children: <Widget>[
Container( //this is the first container
height: double.infinity
),
secondWidget(
)
],
)
Let me know if you have further query. Happy coding!
You can use Expanded widget. It divides siblings to the same height or width.
here is the code:
Row(
children: <Widget>[
Expanded(
child: Container(
color: Colors.red,
),
),
Expanded(
child: Container(
color: Colors.green,
),
)
And here is the result:
That is so easy. I wish it could help.
I've used both Expanded and Flexible widgets and they both seem to work the same.
What is the difference between Expanded and Flexible?
Scaffold(
appBar: AppBar(),
body: Column(
children: <Widget>[
Row(
children: <Widget>[
buildExpanded(),
buildFlexible(),
],
),
Row(
children: <Widget>[
buildExpanded(),
buildExpanded(),
],
),
Row(
children: <Widget>[
buildFlexible(),
buildFlexible(),
],
),
],
),
);
Expanded is just a shorthand for Flexible
Using Expanded this way:
Expanded(
child: Foo(),
);
is strictly equivalent to:
Flexible(
fit: FlexFit.tight,
child: Foo(),
);
You may want to use Flexible over Expanded when you want a different fit, useful in some responsive layouts.
The difference between FlexFit.tight and FlexFit.loose is that loose will allow its child to have a maximum size while tight forces that child to fill all the available space.
Widget under Flexible are by default WRAP_CONTENT although you can change it using parameter fit.
Widget under Expanded is MATCH_PARENT you can change it using flex.
Expanded - it is Flexible with set fit
class Expanded extends Flexible {
const Expanded({
Key key,
int flex = 1,
#required Widget child,
}) : super(
key: key,
flex: flex,
fit: FlexFit.tight,
child: child
);
}
You may use Flexible to resize the widgets in rows and columns. It's mainly used to adjust the space of the different child widgets while keeping the relation with their parent widgets.
Meanwhile, Expanded changes the constraints sent to the children of rows and columns; it helps to fill the available spaces there. Therefore, when you wrap your child in an Expanded widget it fills up the empty spaces.
Providing these videos from the Flutter's Official YouTube channel just to help out people, who might look for this in the upcoming future...
Expanded:
Flexible:
Expanded() is nothing more than Flexible() with
Flexible (fit: FlexFit.tight) = Expanded()
but, Flexible uses fit :FlexFit.loose by default.
FlexFit.tight = Wants to fit tight into parent taking as much space as possible.
FlexFit.loose = Wants to fit loose into parent taking as little space as possible for itself.
Expanded changes the constraints of a child widget so it fills any empty space. Expanded widget is a specialised Flexible widget with a set fit - Flexible(fit: FlexFit.tight. Expanded widgets also have a flex property.
Flexible makes the child widget flexible and resizable. You can add the flex or fit property to adjust the size and spacing.
Flexible fit properties include:
FlexFit.loose - The widget’s preferred size is used. (Default)
FlexFit.tight - Forces the widget to fill all of its extra space.
Flexible default will share the available space of the parent widget, but will NOT force the child to fit the space.
Expanded will share the available space of the parent widget, and force the child widget to change its width/height to fill the available space.
In fact, Expanded extends Flexible, which is a Flexible with FlexFit.tight. See the official document.
Here is a Container widget and three Flexible Widgets(flex = 1, fit = FlexFit.loose) in a row. We can see that the three flexible widgets share the same maxWidth (1/3 of the available screen width), and the blue one wants bigger than it, and the others want smaller. But as we can see, the blue guy has maxWidth as its width and the other widgets' width just fit their content.
Here is the code of the image above up:
Row(
mainAxisSize: MainAxisSize.max,
children: [
Container(
color: Colors.teal,
child: Text(
'Container Text ',
)),
Flexible(
child: Container(
color: Colors.blue,
child: Text(' Text.Flexible Text.Flexible Text.Flexible.')),
),
Flexible(
child: Container(
color: Colors.yellow, child: Text('Flexible Text.')),
),
Flexible(
child: Container(
color: Colors.lightGreen, child: Text('Flexible.')),
),
],
)