ReactiveNullableList<T> class

A reactive widget that renders a UI based on a nullable list.

This widget listens to a reactiveKey and rebuilds when notified via refresh or refreshOnly. It handles three scenarios:

If values is null, it renders ifNull.
If values is empty, it renders ifEmpty.
If values is non-empty, it renders builder with the list.

Useful for conditionally rendering lists with loading and empty states.

Example:

List<String>? users;

ReactiveNullableList<String>(
  values: users,
  builder: (list) => ListView(children: list.map(Text.new).toList()),
  ifNull: CircularProgressIndicator(),
  ifEmpty: Text("No users found"),
)

// Later...
users = ["Alice", "Bob"];
refresh();

Inheritance

Constructors

ReactiveNullableList({Key? key, List<T>? values, Widget ifNull = const Nothing(), Widget ifEmpty = const Nothing(), required Widget builder(List<T>), Key? reactiveKey}): Creates a ReactiveNullableList that rebuilds reactively and displays different widgets depending on the state of values.

Properties

builder → Widget Function(List<T>): Builder called when values is non-null and not empty.
final
hashCode → int: The hash code for this object.
no setterinherited
ifEmpty → Widget: Widget to display if values is an empty list.
final
ifNull → Widget: Widget to display if values is null.
final
key → Key?: Controls how one widget replaces another widget in the tree.
finalinherited
reactiveKey → Key: Key used to identify which reactive updates this widget listens to.
final
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
values → List<T>?: The list of values to evaluate and pass to builder.
final

Methods

createElement() → StatefulElement: Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → State<ReactiveNullableList<T>>: 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.
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

Operators

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