LayoutBoxViewport class
A viewport widget that manages the rendering of layout children with scrolling support.
LayoutBoxViewport is responsible for creating and managing a RenderLayoutBox that handles the actual layout calculations and rendering. It provides the connection between the widget layer and the render object layer, managing scrolling offsets, text direction, and layout configuration.
This widget is typically not used directly but is created internally by LayoutBoxWidget to handle the scrolling and viewport logic.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- RenderObjectWidget
- MultiChildRenderObjectWidget
- LayoutBoxViewport
Constructors
-
LayoutBoxViewport({Key? key, required TextDirection textDirection, required bool reversePaint, required Axis mainScrollDirection, required ViewportOffset horizontal, required ViewportOffset vertical, required AxisDirection horizontalAxisDirection, required AxisDirection verticalAxisDirection, required Layout layout, required LayoutOverflow horizontalOverflow, required LayoutOverflow verticalOverflow, required TextBaseline? textBaseline, required BorderRadius borderRadius, required Clip clipBehavior, required List<
Widget> children}) -
Creates a layout viewport with the specified configuration.
const
Properties
- borderRadius → BorderRadius
-
The border radius applied to the viewport's background and clipping.
final
-
children
→ List<
Widget> -
The widgets below this widget in the tree.
finalinherited
- clipBehavior → Clip
-
How to clip content that extends beyond the viewport bounds.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- horizontal → ViewportOffset
-
The horizontal scroll offset for this viewport.
final
- horizontalAxisDirection → AxisDirection
-
The direction of the horizontal axis.
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 children.
final
- mainScrollDirection → Axis
-
The primary scrolling axis for this viewport.
final
- reversePaint → bool
-
Whether to reverse the paint order of children.
final
- runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
- textBaseline → TextBaseline?
-
The text baseline to use for text alignment within the layout.
final
- textDirection → TextDirection
-
The text direction for resolving directional layout properties.
final
- vertical → ViewportOffset
-
The vertical scroll offset for this viewport.
final
- verticalAxisDirection → AxisDirection
-
The direction of the vertical axis.
final
- verticalOverflow → LayoutOverflow
-
How to handle content that exceeds vertical bounds.
final
Methods
-
createElement(
) → MultiChildRenderObjectElement -
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
-
createRenderObject(
BuildContext context) → RenderObject -
Creates the render object that will perform the actual layout and painting.
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.
inherited
-
didUnmountRenderObject(
covariant RenderObject renderObject) → void -
This method is called when a RenderObject that was previously
associated with this widget is removed from the render tree.
The provided RenderObject will be of the same type as the one created by
this widget's createRenderObject method.
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 RenderLayoutBox renderObject) → void -
Updates the render object when widget properties change.
override
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited