SlottedMultiChildRenderObjectWidgetMixin<S> mixin Null safety

A mixin for a RenderObjectWidget that configures a RenderObject subclass, which organizes its children in different slots.

Implementers of this mixin have to provide the list of available slots by overriding slots. The list of slots must never change for a given class implementing this mixin. In the common case, Enum values are used as slots and slots is typically implemented to return the value of the enum's values getter.

Furthermore, childForSlot must be implemented to return the current widget configuration for a given slot.

The RenderObject returned by createRenderObject and updated by updateRenderObject must implement the SlottedContainerRenderObjectMixin.

The type parameter S is the type for the slots to be used by this RenderObjectWidget and the RenderObject it configures. In the typical case, S is an Enum type.

link
This example uses the SlottedMultiChildRenderObjectWidgetMixin in combination with the SlottedContainerRenderObjectMixin to implement a widget that provides two slots: topLeft and bottomRight. The widget arranges the children in those slots diagonally.
To create a local project with this code sample, run:
flutter create --sample=widgets.SlottedMultiChildRenderObjectWidgetMixin.1 mysample

See also:

Superclass Constraints

Properties

slots → Iterable<S>
Returns a list of all available slots.
@protected, read-only
key → Key?
Controls how one widget replaces another widget in the tree.
final, inherited
hashCode → int
The hash code for this object.
@nonVirtual, read-only, inherited
runtimeType → Type
A representation of the runtime type of the object.
read-only, inherited

Methods

childForSlot(S slot) → Widget?
Returns the widget that is currently occupying the provided slot.
@protected
createElement() → SlottedRenderObjectElement<S>
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
override
createRenderObject(BuildContext context) → SlottedContainerRenderObjectMixin<S>
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget.
override
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
@protected, 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.
@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 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 SlottedContainerRenderObjectMixin<S> 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

Operators

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