Center class Null safety

A widget that centers its child within itself.

This widget will be as big as possible if its dimensions are constrained and widthFactor and heightFactor are null. If a dimension is unconstrained and the corresponding size factor is null then the widget will match its child's size in that dimension. If a size factor is non-null then the corresponding dimension of this widget will be the product of the child's dimension and the size factor. For example if widthFactor is 2.0 then the width of this widget will always be twice its child's width.

See also:

  • Align, which lets you arbitrarily position a child within itself, rather than just centering it.
  • Row, a widget that displays its children in a horizontal array.
  • Column, a widget that displays its children in a vertical array.
  • Container, a convenience widget that combines common painting, positioning, and sizing widgets.
  • The catalog of layout widgets.
Inheritance

Constructors

Center({Key? key, double? widthFactor, double? heightFactor, Widget? child})
Creates a widget that centers its child.
const

Properties

alignment → AlignmentGeometry
How to align the child.
finalinherited
child → Widget?
The widget below this widget in the tree.
finalinherited
hashCode → int
The hash code for this object.
nonVirtual">@nonVirtualread-onlyinherited
heightFactor → double?
If non-null, sets its height to the child's height multiplied by this factor.
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.
read-onlyinherited
widthFactor → double?
If non-null, sets its width to the child's width multiplied by this factor.
finalinherited

Methods

createElement() → SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
createRenderObject(BuildContext context) → RenderPositionedBox
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.
protected">@protectedinherited
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.
protected">@protectedinherited
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
updateRenderObject(BuildContext context, covariant RenderPositionedBox 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.
nonVirtual">@nonVirtualinherited