LidListener<T> class

Takes a LidWidgetListener and an optional stateNotifier and invokes the listener in response to state changes in the stateNotifier. It should be used for functionality that needs to occur only in response to a state change such as navigation, showing a SnackBar, showing a Dialog, etc... The listener is guaranteed to only be called once for each state change unlike the builder in LidBuilder. Specify the stateNotifier.

LidListener<StateType>(
  stateNotifier: stateNotifier,
  listener: (context, state) {
    // do stuff here based on State Notifier's state
  },
  child: Container(),
)

An optional listenWhen can be implemented for more granular control over when listener is called. listenWhen will be invoked on each stateNotifier state change. listenWhen takes the previous state and current state and must return a bool which determines whether or not the listener function will be invoked. The previous state will be initialized to the state of the stateNotifier when the LidListener is initialized. listenWhen is optional and if omitted, it will default to true.

LidListener<StateType>(
  stateNotifier: stateNotifier,
  listenWhen: (previous, current) {
    // return true/false to determine whether or not
    // to invoke listener with state
  },
  listener: (context, state) {
    // do stuff here based on State Notifier's state
  }
  child: Container(),
)
Inheritance

Constructors

LidListener({Key? key, required LidWidgetListener<T> listener, required StateNotifier<T> stateNotifier, ListenerCondition<T>? listenWhen, Widget? child})
const

Properties

child → Widget?
The widget which will be rendered as a descendant of the LidListener.
final
hashCode → int
The hash code for this object.
no setterinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
listener → LidWidgetListener<T>
The LidWidgetListener which will be called on every state change. This listener should be used for any code which needs to execute in response to a state change.
final
listenWhen → ListenerCondition<T>?
An optional listenWhen can be implemented for more granular control over when listener is called. listenWhen will be invoked on each stateNotifier state change. listenWhen takes the previous state and current state and must return a bool which determines whether or not the listener function will be invoked. The previous state will be initialized to the state of the stateNotifier when the LidListener is initialized. listenWhen is optional and if omitted, it will default to true.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
stateNotifier → StateNotifier<T>
The stateNotifier that the LidBuilder will interact with.
final

Methods

createElement() → SingleChildStatefulElement
Creates a StatefulElement to manage this widget's location in the tree.
inherited
createState() → _LidListenerState<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.
override
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}) → 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