Spacer class Null safety

Spacer creates an adjustable, empty spacer that can be used to tune the spacing between widgets in a Flex container, like Row or Column.

The Spacer widget will take up any available space, so setting the Flex.mainAxisAlignment on a flex container that contains a Spacer to MainAxisAlignment.spaceAround, MainAxisAlignment.spaceBetween, or MainAxisAlignment.spaceEvenly will not have any visible effect: the Spacer has taken up all of the additional space, therefore there is none left to redistribute.

link 
Row(
  children: const <Widget>[
    Text('Begin'),
    Spacer(), // Defaults to a flex of one.
    Text('Middle'),
    // Gives twice the space between Middle and End than Begin and Middle.
    Spacer(flex: 2),
    Text('End'),
  ],
)

See also:

  • Row and Column, which are the most common containers to use a Spacer in.
  • SizedBox, to create a box with a specific size and an optional child.
Inheritance

Constructors

Spacer({Key? key, int flex = 1})
Creates a flexible space to insert into a Flexible widget.
const

Properties

flex → int
The flex factor to use in determining how much space to take up.
final
hashCode → int
The hash code for this object.
nonVirtual">@nonVirtualread-onlyinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
runtimeType → Type
A representation of the runtime type of the object.
read-onlyinherited

Methods

build(BuildContext context) → Widget
Describes the part of the user interface represented by this widget.
override
createElement() → StatelessElement
Creates a StatelessElement to manage this widget's location in the tree.
inherited
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
protected">@protectedinherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent 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}) → 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.
nonVirtual">@nonVirtualinherited