UnconstrainedBox class

A widget that imposes no constraints on its child, allowing it to render at its "natural" size.

This allows a child to render at the size it would render if it were alone on an infinite canvas with no constraints. This container will then attempt to adopt the same size, within the limits of its own constraints. If it ends up with a different size, it will align the child based on alignment. If the box cannot expand enough to accommodate the entire child, the child will be clipped.

In debug mode, if the child overflows the container, a warning will be printed on the console, and black and yellow striped areas will appear where the overflow occurs.

See also:

  • ConstrainedBox, for a box which imposes constraints on its child.
  • Align, which loosens the constraints given to the child rather than removing them entirely.
  • Container, a convenience widget that combines common painting, positioning, and sizing widgets.
  • OverflowBox, a widget that imposes different constraints on its child than it gets from its parent, possibly allowing the child to overflow the parent.
Inheritance

Constructors

UnconstrainedBox({Key key, Widget child, TextDirection textDirection, AlignmentGeometry alignment: Alignment.center, Axis constrainedAxis })
Creates a widget that imposes no constraints on its child, allowing it to render at its "natural" size. If the child overflows the parents constraints, a warning will be given in debug mode.
const

Properties

alignment → AlignmentGeometry
The alignment to use when laying out the child. [...]
final
constrainedAxis → Axis
The axis to retain constraints on, if any. [...]
final
textDirection → TextDirection
The text direction to use when interpreting the alignment if it is an AlignmentDirectional.
final
child → Widget
The widget below this widget in the tree. [...]
final, inherited
hashCode → int
The hash code for this object. [...]
read-only, inherited
key → Key
Controls how one widget replaces another widget in the tree. [...]
final, inherited
runtimeType → Type
A representation of the runtime type of the object.
read-only, inherited

Methods

createRenderObject(BuildContext context) → RenderUnconstrainedBox
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget. [...]
override
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node. [...]
override
updateRenderObject(BuildContext context, covariant RenderUnconstrainedBox 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. [...]
override
createElement() → SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children. [...]
@protected, 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, 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 toStringDeep. [...]
inherited
toString({DiagnosticLevel minLevel: DiagnosticLevel.debug }) → String
Returns 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 ==(dynamic other) → bool
The equality operator. [...]
inherited