LayoutBoxWidget class

A flexible layout container that supports scrolling and custom layout algorithms.

LayoutBox is a fundamental building block for creating custom layouts in Flutter. It provides scrolling capabilities, overflow handling, and integrates with custom layout algorithms through the Layout interface.

Basic Usage

LayoutBoxWidget(
  layout: FlexLayout(
    direction: FlexDirection.row,
    alignItems: BoxAlignmentGeometry.center,
  ),
  children: [
    Text('Item 1'),
    Text('Item 2'),
  ],
)

Scrolling

LayoutBox automatically provides scrolling when content overflows:

Layout Algorithms

The layout property defines how children are positioned and sized. Built-in layouts include FlexLayout for flexbox behavior, but custom layouts can be implemented by extending the Layout class.

Text Direction

The textDirection property affects directional alignments and scrolling. If null, it uses the ambient Directionality from the widget tree.

Inheritance
Available extensions

Constructors

LayoutBoxWidget({Key? key, TextDirection? textDirection, bool reversePaint = false, LayoutOverflow horizontalOverflow = LayoutOverflow.visible, LayoutOverflow verticalOverflow = LayoutOverflow.visible, ScrollController? horizontalController, ScrollController? verticalController, DiagonalDragBehavior diagonalDragBehavior = DiagonalDragBehavior.free, Axis mainScrollDirection = Axis.vertical, TextBaseline? textBaseline, BorderRadiusGeometry? borderRadius, Clip clipBehavior = Clip.hardEdge, bool reverseHorizontalScroll = false, bool reverseVerticalScroll = false, required Layout layout, required List<Widget> children})
Creates a layout container with the specified properties.
const

Properties

asAbsoluteItem → Widget

Available on Widget, provided by the WidgetExtension extension

Explicitly wraps this widget as an AbsoluteItem.
no setter
asFlexItem → Widget

Available on Widget, provided by the WidgetExtension extension

Explicitly wraps this widget as a FlexItem.
no setter
borderRadius → BorderRadiusGeometry?
The border radius applied to the container's background and clipping.
final
children → List<Widget>
The list of child widgets to layout.
final
clipBehavior → Clip
How to clip content that extends beyond the container bounds.
final
diagonalDragBehavior → DiagonalDragBehavior
Controls how diagonal drag gestures are interpreted.
final
hashCode → int
The hash code for this object.
no setterinherited
horizontalController → ScrollController?
Controller for horizontal scrolling.
final
horizontalOverflow → LayoutOverflow
How to handle content that exceeds horizontal bounds.
final
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
layout → Layout
The layout algorithm to use for positioning and sizing children.
final
mainScrollDirection → Axis
The primary scrolling axis for layout optimizations.
final
reverseHorizontalScroll → bool
Whether to reverse the horizontal scroll direction.
final
reversePaint → bool
Whether to reverse the paint order of children.
final
reverseVerticalScroll → bool
Whether to reverse the vertical scroll direction.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
textBaseline → TextBaseline?
The text baseline to use for text alignment.
final
textDirection → TextDirection?
The text direction for resolving directional layout properties.
final
verticalController → ScrollController?
Controller for vertical scrolling.
final
verticalOverflow → LayoutOverflow
How to handle content that exceeds vertical bounds.
final

Methods

aspectRatio(double aspectRatio, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the aspect ratio constraint for this widget.
bottom(PositionUnit bottom, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the distance from the bottom edge of the parent container.
constrained({SizeUnit? minWidth, SizeUnit? maxWidth, SizeUnit? minHeight, SizeUnit? maxHeight, Key? key}) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets comprehensive size constraints including both minimum and maximum bounds.
createElement() → StatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → State<LayoutBoxWidget>
Creates the mutable state for this widget at a given location in the tree.
override
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.
override
flexGrow(double flexGrow, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the flex grow factor for this widget within a flex container.
flexShrink(double flexShrink, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the flex shrink factor for this widget within a flex container.
height(SizeUnit height, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the height of this widget using a SizeUnit.
id(Object valueKey) → Widget

Available on Widget, provided by the WidgetExtension extension

Assigns a ValueKey to this widget using the provided value.
key(Key key) → Widget

Available on Widget, provided by the WidgetExtension extension

Assigns a Key to this widget.
left(PositionUnit left, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the distance from the left edge of the parent container.
maxHeight(SizeUnit maxHeight, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the maximum height constraint for this widget using a SizeUnit.
maxSized({SizeUnit? maxWidth, SizeUnit? maxHeight, Key? key}) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets maximum width and height constraints simultaneously.
maxWidth(SizeUnit maxWidth, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the maximum width constraint for this widget using a SizeUnit.
minHeight(SizeUnit minHeight, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the minimum height constraint for this widget using a SizeUnit.
minSized({SizeUnit? minWidth, SizeUnit? minHeight, Key? key}) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets minimum width and height constraints simultaneously.
minWidth(SizeUnit minWidth, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the minimum width constraint for this widget using a SizeUnit.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
paintOrder(int paintOrder, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the paint order for this widget within its parent container.
position(PositionType position, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the position type for this widget to control positioning context.
positioned({PositionUnit? top, PositionUnit? left, PositionUnit? bottom, PositionUnit? right, Key? key}) → Widget

Available on Widget, provided by the WidgetExtension extension

Positions the widget using multiple edge offsets simultaneously.

Available on Widget, provided by the WidgetExtension extension

Sets the distance from the right edge of the parent container.
selfAligned(BoxAlignmentGeometry alignSelf, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the alignment of this widget within its parent flex container.
sized({SizeUnit? width, SizeUnit? height, Key? key}) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets both width and height dimensions simultaneously.
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
top(PositionUnit top, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the distance from the top edge of the parent container.
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
width(SizeUnit width, [Key? key]) → Widget

Available on Widget, provided by the WidgetExtension extension

Sets the width of this widget using a SizeUnit.

Operators

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