ConstrainedLayoutBuilder<ConstraintType extends Constraints> class
abstract
A specialized AbstractLayoutBuilder whose widget subtree depends on the
incoming ConstraintType
that will be imposed on the widget.
The builder function is called in the following situations:
- The first time the widget is laid out.
- When the parent widget passes different layout constraints.
- When the parent widget updates this widget and updateShouldRebuild returns
true
. - When the dependencies that the builder function subscribes to change.
The builder function is not called during layout if the parent passes the same constraints repeatedly.
In the event that an ancestor skips the layout of this subtree so the
constraints become outdated, the builder
rebuilds with the last known
constraints.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- RenderObjectWidget
- AbstractLayoutBuilder<
ConstraintType> - ConstrainedLayoutBuilder
- Implementers
Constructors
- ConstrainedLayoutBuilder({Key? key, required Widget builder(BuildContext context, ConstraintType constraints)})
-
Creates a widget that defers its building until layout.
const
Properties
- builder → Widget Function(BuildContext context, ConstraintType constraints)
-
Called at layout time to construct the widget tree.
final
- hashCode → int
-
The hash code for this object.
no setterinherited
- 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
Methods
-
createElement(
) → RenderObjectElement -
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
-
createRenderObject(
BuildContext context) → RenderAbstractLayoutBuilderMixin< ConstraintType, RenderObject> -
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 RenderObject 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
-
updateShouldRebuild(
covariant AbstractLayoutBuilder< ConstraintType> oldWidget) → bool -
Whether builder needs to be called again even if the layout constraints
are the same.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited