A widget that displays its children in a horizontal array. The <a dir="ltr" href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>widget does not scroll (and in general it is considered an error to have more children in a <a dir="ltr" href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>than will fit in the available room). If you have a line of widgets and want them to be able to scroll if there is insufficient room, consider using a <a dir="ltr" href="https://api.flutter.dev/flutter/widgets/ListView-class.html">ListView </a>.

Row Widget in Flutter 

<h1 dir="ltr">Row class 
 <a href="https://dart.dev/null-safety" title="Supports the null safety language feature." dir="ltr">Null safety</a>
 
</h1>A widget that displays its children in a horizontal array.To cause a child to expand to fill the available horizontal space, wrap the
child in an <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html" dir="ltr">Expanded</a> widget.The <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> widget does not scroll (and in general it is considered an error
to have more children in a <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> than will fit in the available room). If
you have a line of widgets and want them to be able to scroll if there is
insufficient room, consider using a <a href="https://api.flutter.dev/flutter/widgets/ListView-class.html" dir="ltr">ListView</a>.For a vertical variant, see <a href="https://api.flutter.dev/flutter/widgets/Column-class.html" dir="ltr">Column</a>.If you only have one child, then consider using <a href="https://api.flutter.dev/flutter/widgets/Align-class.html" dir="ltr">Align</a> or <a href="https://api.flutter.dev/flutter/widgets/Center-class.html" dir="ltr">Center</a> to
position the child.<div><button selected="">Sample</button></div><div>
This example divides the available space into three (horizontally), and
places text centered in the first two cells and the Flutter logo centered in
the third:</div><img src="https://flutter.github.io/assets-for-api-docs/assets/widgets/row.png" alt="" width="400" height="250"><div><button title="Copy to clipboard" onclick="copyTextToClipboard(findSiblingWithId(this, 'sample-code'));" dir="ltr">
 assignment
 </button></div><PRE><code dir="ltr">Row(
 children: const &lt;Widget&gt;[
 Expanded(
 child: Text('Deliver features faster', textAlign: TextAlign.center),
 ),
 Expanded(
 child: Text('Craft beautiful UIs', textAlign: TextAlign.center),
 ),
 Expanded(
 child: FittedBox(
 fit: BoxFit.contain, // otherwise the logo will be tiny
 child: FlutterLogo(),
 ),
 ),
 ],
)</code></PRE><h2>Troubleshooting</h2><h3>Why does my row have a yellow and black warning stripe?</h3>If the non-flexible contents of the row (those that are not wrapped in
<a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html" dir="ltr">Expanded</a> or <a href="https://api.flutter.dev/flutter/widgets/Flexible-class.html" dir="ltr">Flexible</a> widgets) are together wider than the row itself,
then the row is said to have overflowed. When a row overflows, the row does
not have any remaining space to share between its <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html" dir="ltr">Expanded</a> and <a href="https://api.flutter.dev/flutter/widgets/Flexible-class.html" dir="ltr">Flexible</a>
children. The row reports this by drawing a yellow and black striped
warning box on the edge that is overflowing. If there is room on the outside
of the row, the amount of overflow is printed in red lettering.<h4>Story time</h4>Suppose, for instance, that you had this code:<PRE><code dir="ltr">Row(
 children: &lt;Widget&gt;[
 const FlutterLogo(),
 const Text("Flutter's hot reload helps you quickly and easily experiment, build UIs, add features, and fix bug faster. Experience sub-second reload times, without losing state, on emulators, simulators, and hardware for iOS and Android."),
 const Icon(Icons.sentiment_very_satisfied),
 ],
)
</code></PRE>The row first asks its first child, the <a href="https://api.flutter.dev/flutter/material/FlutterLogo-class.html" dir="ltr">FlutterLogo</a>, to lay out, at
whatever size the logo would like. The logo is friendly and happily decides
to be 24 pixels to a side. This leaves lots of room for the next child. The
row then asks that next child, the text, to lay out, at whatever size it
thinks is best.At this point, the text, not knowing how wide is too wide, says "Ok, I will
be thiiiiiiiiiiiiiiiiiiiis wide.", and goes well beyond the space that the
row has available, not wrapping. The row responds, "That's not fair, now I
have no more room available for my other children!", and gets angry and
sprouts a yellow and black strip.<img src="https://flutter.github.io/assets-for-api-docs/assets/widgets/row_error.png" alt="" width="400" height="250">The fix is to wrap the second child in an <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html" dir="ltr">Expanded</a> widget, which tells the
row that the child should be given the remaining room:<PRE><code dir="ltr">Row(
 children: &lt;Widget&gt;[
 const FlutterLogo(),
 const Expanded(
 child: Text("Flutter's hot reload helps you quickly and easily experiment, build UIs, add features, and fix bug faster. Experience sub-second reload times, without losing state, on emulators, simulators, and hardware for iOS and Android."),
 ),
 const Icon(Icons.sentiment_very_satisfied),
 ],
)
</code></PRE>Now, the row first asks the logo to lay out, and then asks the icon to lay
out. The <a href="https://api.flutter.dev/flutter/widgets/Icon-class.html" dir="ltr">Icon</a>, like the logo, is happy to take on a reasonable size (also
24 pixels, not coincidentally, since both <a href="https://api.flutter.dev/flutter/material/FlutterLogo-class.html" dir="ltr">FlutterLogo</a> and <a href="https://api.flutter.dev/flutter/widgets/Icon-class.html" dir="ltr">Icon</a> honor the
ambient <a href="https://api.flutter.dev/flutter/widgets/IconTheme-class.html" dir="ltr">IconTheme</a>). This leaves some room left over, and now the row tells
the text exactly how wide to be: the exact width of the remaining space. The
text, now happy to comply to a reasonable request, wraps the text within
that width, and you end up with a paragraph split over several lines.<img src="https://flutter.github.io/assets-for-api-docs/assets/widgets/row_fixed.png" alt="" width="400" height="250">The <a href="https://api.flutter.dev/flutter/widgets/Flex/textDirection.html" dir="ltr">textDirection</a> property controls the direction that children are rendered in.
<a href="https://api.flutter.dev/flutter/dart-ui/TextDirection-class.html" dir="ltr">TextDirection.ltr</a> is the default <a href="https://api.flutter.dev/flutter/widgets/Flex/textDirection.html" dir="ltr">textDirection</a> of <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> children, so the first
child is rendered at the <code dir="ltr">start</code> of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a>, to the left, with subsequent children
following to the right. If you want to order children in the opposite
direction (right to left), then <a href="https://api.flutter.dev/flutter/widgets/Flex/textDirection.html" dir="ltr">textDirection</a> can be set to
<a href="https://api.flutter.dev/flutter/dart-ui/TextDirection-class.html" dir="ltr">TextDirection.rtl</a>. This is shown in the example below<PRE><code dir="ltr">Row(
 textDirection: TextDirection.rtl,
 children: &lt;Widget&gt;[
 const FlutterLogo(),
 const Expanded(
 child: Text("Flutter's hot reload helps you quickly and easily experiment, build UIs, add features, and fix bug faster. Experience sub-second reload times, without losing state, on emulators, simulators, and hardware for iOS and Android."),
 ),
 const Icon(Icons.sentiment_very_satisfied),
 ],
)
</code></PRE><img src="https://flutter.github.io/assets-for-api-docs/assets/widgets/row_textDirection.png" alt="" width="400" height="250"><h2>Layout algorithm</h2>This section describes how a <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> is rendered by the framework.
See <a href="https://api.flutter.dev/flutter/rendering/BoxConstraints-class.html" dir="ltr">BoxConstraints</a> for an introduction to box layout models.Layout for a <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> proceeds in six steps:<OL><LI>Layout each child a null or zero flex factor (e.g., those that are not
<a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html" dir="ltr">Expanded</a>) with unbounded horizontal constraints and the incoming
vertical constraints. If the <a href="https://api.flutter.dev/flutter/widgets/Flex/crossAxisAlignment.html" dir="ltr">crossAxisAlignment</a> is
<a href="https://api.flutter.dev/flutter/rendering/CrossAxisAlignment-class.html" dir="ltr">CrossAxisAlignment.stretch</a>, instead use tight vertical constraints that
match the incoming max height.</LI><LI>Divide the remaining horizontal space among the children with non-zero
flex factors (e.g., those that are <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html" dir="ltr">Expanded</a>) according to their flex
factor. For example, a child with a flex factor of 2.0 will receive twice
the amount of horizontal space as a child with a flex factor of 1.0.</LI><LI>Layout each of the remaining children with the same vertical constraints
as in step 1, but instead of using unbounded horizontal constraints, use
horizontal constraints based on the amount of space allocated in step 2.
Children with <a href="https://api.flutter.dev/flutter/widgets/Flexible/fit.html" dir="ltr">Flexible.fit</a> properties that are <a href="https://api.flutter.dev/flutter/rendering/FlexFit-class.html" dir="ltr">FlexFit.tight</a> are
given tight constraints (i.e., forced to fill the allocated space), and
children with <a href="https://api.flutter.dev/flutter/widgets/Flexible/fit.html" dir="ltr">Flexible.fit</a> properties that are <a href="https://api.flutter.dev/flutter/rendering/FlexFit-class.html" dir="ltr">FlexFit.loose</a> are
given loose constraints (i.e., not forced to fill the allocated space).</LI><LI>The height of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> is the maximum height of the children (which will
always satisfy the incoming vertical constraints).</LI><LI>The width of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> is determined by the <a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisSize.html" dir="ltr">mainAxisSize</a> property. If
the <a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisSize.html" dir="ltr">mainAxisSize</a> property is <a href="https://api.flutter.dev/flutter/rendering/MainAxisSize-class.html" dir="ltr">MainAxisSize.max</a>, then the width of the
<a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> is the max width of the incoming constraints. If the <a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisSize.html" dir="ltr">mainAxisSize</a>
property is <a href="https://api.flutter.dev/flutter/rendering/MainAxisSize-class.html" dir="ltr">MainAxisSize.min</a>, then the width of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html" dir="ltr">Row</a> is the sum
of widths of the children (subject to the incoming constraints).</LI><LI>Determine the position for each child according to the
<a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisAlignment.html" dir="ltr">mainAxisAlignment</a> and the <a href="https://api.flutter.dev/flutter/widgets/Flex/crossAxisAlignment.html" dir="ltr">crossAxisAlignment</a>. For example, if the
<a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisAlignment.html" dir="ltr">mainAxisAlignment</a> is <a href="https://api.flutter.dev/flutter/rendering/MainAxisAlignment-class.html" dir="ltr">MainAxisAlignment.spaceBetween</a>, any horizontal
space that has not been allocated to children is divided evenly and
placed between the children.</LI></OL>See also:<UL><LI><a href="https://api.flutter.dev/flutter/widgets/Column-class.html" dir="ltr">Column</a>, for a vertical equivalent.</LI><LI><a href="https://api.flutter.dev/flutter/widgets/Flex-class.html" dir="ltr">Flex</a>, if you don't know in advance if you want a horizontal or vertical
arrangement.</LI><LI><a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html" dir="ltr">Expanded</a>, to indicate children that should take all the remaining room.</LI><LI><a href="https://api.flutter.dev/flutter/widgets/Flexible-class.html" dir="ltr">Flexible</a>, to indicate children that should share the remaining room but
that may by sized smaller (leaving some remaining room unused).</LI><LI><a href="https://api.flutter.dev/flutter/widgets/Spacer-class.html" dir="ltr">Spacer</a>, a widget that takes up space proportional to its flex value.</LI></UL>

API docs for the Row class from the widgets library, for the Dart programming language.

computerscience

Computer Science

A widget that displays its children in a horizontal array.

To cause a child to expand to fill the available horizontal space, wrap the child in an <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html">Expanded </a>widget.

The <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>widget does not scroll (and in general it is considered an error to have more children in a <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>than will fit in the available room). If you have a line of widgets and want them to be able to scroll if there is insufficient room, consider using a <a href="https://api.flutter.dev/flutter/widgets/ListView-class.html">ListView </a>.

For a vertical variant, see <a href="https://api.flutter.dev/flutter/widgets/Column-class.html">Column </a>.

If you only have one child, then consider using <a href="https://api.flutter.dev/flutter/widgets/Align-class.html">Align </a>or <a href="https://api.flutter.dev/flutter/widgets/Center-class.html">Center </a>to position the child.

Why does my row have a yellow and black warning stripe?

If the non-flexible contents of the row (those that are not wrapped in <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html">Expanded </a>or <a href="https://api.flutter.dev/flutter/widgets/Flexible-class.html">Flexible </a>widgets) are together wider than the row itself, then the row is said to have overflowed. When a row overflows, the row does not have any remaining space to share between its <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html">Expanded </a>and <a href="https://api.flutter.dev/flutter/widgets/Flexible-class.html">Flexible </a>children. The row reports this by drawing a yellow and black striped warning box on the edge that is overflowing. If there is room on the outside of the row, the amount of overflow is printed in red lettering.

Suppose, for instance, that you had this code:

The row first asks its first child, the <a href="https://api.flutter.dev/flutter/material/FlutterLogo-class.html">FlutterLogo </a>, to lay out, at whatever size the logo would like. The logo is friendly and happily decides to be 24 pixels to a side. This leaves lots of room for the next child. The row then asks that next child, the text, to lay out, at whatever size it thinks is best.

At this point, the text, not knowing how wide is too wide, says "Ok, I will be thiiiiiiiiiiiiiiiiiiiis wide.", and goes well beyond the space that the row has available, not wrapping. The row responds, "That's not fair, now I have no more room available for my other children!", and gets angry and sprouts a yellow and black strip.

The fix is to wrap the second child in an <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html">Expanded </a>widget, which tells the row that the child should be given the remaining room:

Now, the row first asks the logo to lay out, and then asks the icon to lay out. The <a href="https://api.flutter.dev/flutter/widgets/Icon-class.html">Icon </a>, like the logo, is happy to take on a reasonable size (also 24 pixels, not coincidentally, since both <a href="https://api.flutter.dev/flutter/material/FlutterLogo-class.html">FlutterLogo </a>and <a href="https://api.flutter.dev/flutter/widgets/Icon-class.html">Icon </a>honor the ambient <a href="https://api.flutter.dev/flutter/widgets/IconTheme-class.html">IconTheme </a>). This leaves some room left over, and now the row tells the text exactly how wide to be: the exact width of the remaining space. The text, now happy to comply to a reasonable request, wraps the text within that width, and you end up with a paragraph split over several lines.

The <a href="https://api.flutter.dev/flutter/widgets/Flex/textDirection.html">textDirection </a>property controls the direction that children are rendered in. <a href="https://api.flutter.dev/flutter/dart-ui/TextDirection-class.html">TextDirection.ltr </a>is the default <a href="https://api.flutter.dev/flutter/widgets/Flex/textDirection.html">textDirection </a>of <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>children, so the first child is rendered at the <code>start </code>of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>, to the left, with subsequent children following to the right. If you want to order children in the opposite direction (right to left), then <a href="https://api.flutter.dev/flutter/widgets/Flex/textDirection.html">textDirection </a>can be set to <a href="https://api.flutter.dev/flutter/dart-ui/TextDirection-class.html">TextDirection.rtl </a>. This is shown in the example below

This section describes how a <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>is rendered by the framework. See <a href="https://api.flutter.dev/flutter/rendering/BoxConstraints-class.html">BoxConstraints </a>for an introduction to box layout models.

Layout for a <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>proceeds in six steps:

<ol><li>Layout each child a null or zero flex factor (e.g., those that are not <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html">Expanded </a>) with unbounded horizontal constraints and the incoming vertical constraints. If the <a href="https://api.flutter.dev/flutter/widgets/Flex/crossAxisAlignment.html">crossAxisAlignment </a>is <a href="https://api.flutter.dev/flutter/rendering/CrossAxisAlignment-class.html">CrossAxisAlignment.stretch </a>, instead use tight vertical constraints that match the incoming max height. </li><li>Divide the remaining horizontal space among the children with non-zero flex factors (e.g., those that are <a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html">Expanded </a>) according to their flex factor. For example, a child with a flex factor of 2.0 will receive twice the amount of horizontal space as a child with a flex factor of 1.0. </li><li>Layout each of the remaining children with the same vertical constraints as in step 1, but instead of using unbounded horizontal constraints, use horizontal constraints based on the amount of space allocated in step 2. Children with <a href="https://api.flutter.dev/flutter/widgets/Flexible/fit.html">Flexible.fit </a>properties that are <a href="https://api.flutter.dev/flutter/rendering/FlexFit-class.html">FlexFit.tight </a>are given tight constraints (i.e., forced to fill the allocated space), and children with <a href="https://api.flutter.dev/flutter/widgets/Flexible/fit.html">Flexible.fit </a>properties that are <a href="https://api.flutter.dev/flutter/rendering/FlexFit-class.html">FlexFit.loose </a>are given loose constraints (i.e., not forced to fill the allocated space). </li><li>The height of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>is the maximum height of the children (which will always satisfy the incoming vertical constraints). </li><li>The width of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>is determined by the <a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisSize.html">mainAxisSize </a>property. If the <a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisSize.html">mainAxisSize </a>property is <a href="https://api.flutter.dev/flutter/rendering/MainAxisSize-class.html">MainAxisSize.max </a>, then the width of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>is the max width of the incoming constraints. If the <a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisSize.html">mainAxisSize </a>property is <a href="https://api.flutter.dev/flutter/rendering/MainAxisSize-class.html">MainAxisSize.min </a>, then the width of the <a href="https://api.flutter.dev/flutter/widgets/Row-class.html">Row </a>is the sum of widths of the children (subject to the incoming constraints). </li><li>Determine the position for each child according to the <a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisAlignment.html">mainAxisAlignment </a>and the <a href="https://api.flutter.dev/flutter/widgets/Flex/crossAxisAlignment.html">crossAxisAlignment </a>. For example, if the <a href="https://api.flutter.dev/flutter/widgets/Flex/mainAxisAlignment.html">mainAxisAlignment </a>is <a href="https://api.flutter.dev/flutter/rendering/MainAxisAlignment-class.html">MainAxisAlignment.spaceBetween </a>, any horizontal space that has not been allocated to children is divided evenly and placed between the children. </li> </ol>

<ul><li><a href="https://api.flutter.dev/flutter/widgets/Column-class.html">Column </a>, for a vertical equivalent. </li><li><a href="https://api.flutter.dev/flutter/widgets/Flex-class.html">Flex </a>, if you don't know in advance if you want a horizontal or vertical arrangement. </li><li><a href="https://api.flutter.dev/flutter/widgets/Expanded-class.html">Expanded </a>, to indicate children that should take all the remaining room. </li><li><a href="https://api.flutter.dev/flutter/widgets/Flexible-class.html">Flexible </a>, to indicate children that should share the remaining room but that may by sized smaller (leaving some remaining room unused). </li><li><a href="https://api.flutter.dev/flutter/widgets/Spacer-class.html">Spacer </a>, a widget that takes up space proportional to its flex value. </li> </ul>

Row class - widgets library - Dart API

Row Widget in Flutter

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