NotifierListener<N extends BaseNotifier<S> , S extends Object?> class
A widget that listens to state changes from a BaseNotifier and triggers side effects.
NotifierListener does not rebuild its child when the state changes, but instead calls the listener callback for side effects, optionally using listenWhen to control when to listen.
N is the type of BaseNotifier and S is the type of state managed by the notifier.
- Inheritance
-
- Object
- DiagnosticableTree
- Widget
- StatefulWidget
- NotifierListener
- Implementers
Constructors
- NotifierListener({required Widget child, required void listener(S state), bool listenWhen(S previous, S current)?, N notifier()?, void onInit(N notifier)?, Key? key})
-
Creates a NotifierListener.
const
Properties
- builder → Widget Function(S state)?
-
A function that builds the widget tree based on the current state.
finalinherited
- child → Widget?
-
An optional static child widget to display if
builderis not provided.finalinherited - hashCode → int
-
The hash code for this object.
no setterinherited
- key → Key?
-
Controls how one widget replaces another widget in the tree.
finalinherited
- listener → void Function(S state)
-
Callback for side effects when the state changes.
final
- listenWhen → bool Function(S previous, S current)?
-
Optional predicate to determine whether to call listener when the state changes.
final
- notifier → N Function()?
-
Provides the
BaseNotifierinstance to listen to. If null, the nearestProvideris used.finalinherited - onInit → void Function(N notifier)?
-
An optional callback invoked with the notifier when the widget is initialized.
Note: Do not manually call the notifier's
onInit()method here. The notifier itself will automatically trigger its ownonInit()when it is created, so calling it again would result in duplicate invocations.finalinherited - runtimeType → Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
createElement(
) → StatefulElement -
Creates a StatefulElement to manage this widget's location in the tree.
inherited
-
createState(
) → State< StatefulWidget> -
Creates the mutable state for this widget at a given location in the tree.
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
-
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
-
whenStateChanged(
S previous, S current, VoidCallback _) → void - Called when the notifier's state changes.
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited