ExpandedModifier class

A widget that expands a child of a Row, Column, or Flex so that the child fills the available space.

Using an Expanded widget makes a child of a Row, Column, or Flex expand to fill the available space along the main axis (e.g., horizontally for a Row or vertically for a Column). If multiple children are expanded, the available space is divided among them according to the flex factor.

An Expanded widget must be a descendant of a Row, Column, or Flex, and the path from the Expanded widget to its enclosing Row, Column, or Flex must contain only StatelessWidgets or StatefulWidgets (not other kinds of widgets, like RenderObjectWidgets).

{@tool dartpad} This example shows how to use an Expanded widget in a Column so that its middle child, a Container here, expands to fill the space.

This results in two thin blue boxes with a larger amber box in between.

** See code in examples/api/lib/widgets/basic/expanded.0.dart ** {@end-tool}

{@tool dartpad} This example shows how to use an Expanded widget in a Row with multiple children expanded, utilizing the flex factor to prioritize available space.

This results in a wide amber box, followed by a thin blue box, with a medium width amber box at the end.

** See code in examples/api/lib/widgets/basic/expanded.1.dart ** {@end-tool}

See also:

Inheritance
Available extensions

Constructors

ExpandedModifier({Key? key, Widget? child, int? flex})
Creates a widget that expands a child of a Row, Column, or Flex so that the child fills the available space along the flex widget's main axis.
const

Properties

fit → FlexFit
How a flexible child is inscribed into the available space.
finalinherited
flex → int
The flex factor to use for this child.
finalinherited
hashCode → int
The hash code for this object.
no setterinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
modifierKey → Key?
The actual key of the widget, which Modifier wrapped
finalinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

build(BuildContext context) → Widget
Describes the part of the user interface represented by this widget.
inherited
buildWithChild(BuildContext context, Widget? child) → Widget
A build method that receives an extra child parameter.
inherited
createElement() → SingleChildStatelessElement
Create a SingleChildStatelessElement
inherited
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
inherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
modified() → Modifier

Available on Widget, provided by the ModifierTransformer extension

Transform normal widget to Modifier
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) → String
A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug, int wrapWidth = 65}) → String
Returns a string representation of this node and its descendants.
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String
Returns a one-line detailed description of the object.
inherited
toStringShort() → String
A short, textual description of this widget.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited