SizedBoxResponsive class

A box with a specified size.

If given a child, this widget forces its child to have a specific width and/or height (assuming values are permitted by this widget's parent). If either the width or height is null, this widget will size itself to match the child's size in that dimension.

If not given a child, SizedBox will try to size itself as close to the specified height and width as possible given the parent's constraints. If height or width is null or unspecified, it will be treated as zero.

The new SizedBox.expand constructor can be used to make a SizedBox that sizes itself to fit the parent. It is equivalent to setting width and height to double.infinity.

{@tool snippet}

This snippet makes the child widget (a Card with some Text) have the exact size 200x300, parental constraints permitting:

SizedBox(
  width: 200.0,
  height: 300.0,
  child: const Card(child: Text('Hello World!')),
)

{@end-tool}

See also:

  • ConstrainedBox, a more generic version of this class that takes arbitrary BoxConstraints instead of an explicit width and height.
  • UnconstrainedBox, a container that tries to let its child draw without constraints.
  • FractionallySizedBox, a widget that sizes its child to a fraction of the total available space.
  • AspectRatio, a widget that attempts to fit within the parent's constraints while also sizing its child to match a given aspect ratio.
  • FittedBox, which sizes and positions its child widget to fit the parent according to a given BoxFit discipline.
  • The catalog of layout widgets.
Inheritance

Constructors

SizedBoxResponsive.new({Key? key, double? width, double? height, Widget? child})
Creates a fixed size box. The width and height parameters can be null to indicate that the size of the box should not be constrained in the corresponding dimension.
SizedBoxResponsive.expand({Key? key, Widget? child})
Creates a box that will become as large as its parent allows.
const
SizedBoxResponsive.fromSize({Key? key, Widget? child, Size? size})
Creates a box with the specified size.
SizedBoxResponsive.shrink({Key? key, Widget? child})
Creates a box that will become as small as its parent allows.
const

Properties

child → Widget?
The widget below this widget in the tree.
finalinherited
hashCode → int
The hash code for this object.
no setterinherited
height → double?
If non-null, requires the child to have exactly this height.
finalinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
width → double?
If non-null, requires the child to have exactly this width.
finalinherited

Methods

createElement() → SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
createRenderObject(BuildContext context) → RenderConstrainedBox
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget.
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
didUnmountRenderObject(covariant RenderObject renderObject) → void
A render object previously associated with this widget has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderObject.
inherited
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
updateRenderObject(BuildContext context, covariant RenderConstrainedBox renderObject) → void
Copies the configuration described by this RenderObjectWidget to the given RenderObject, which will be of the same type as returned by this object's createRenderObject.
inherited

Operators

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