VN<T> class

A simplified and enhanced abstraction for working with ValueNotifier.

The VN class streamlines the use of ValueNotifier, adding flexibility through custom change types and advanced features such as merging multiple VN instances.

Features:

Customizable change behaviors via ChangeType.
Built-in listener management.
Easy merging of two VN instances into a single, derived VN.
Utility methods for notifying listeners, silent updates, and conditional updates.

Parameters:

T - The type of the value managed by this VN instance.

Implemented types

ValueListenable<T>

Mixed-in types

ChangeNotifier

Available extensions

Constructors

VN(T initialValue, [ChangeType changeType = ChangeType.smart]): Creates a VN instance with an initial value and optional change behavior.

Properties

changeType → ChangeType: The change behavior applied to this VN.
final
first → T: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns the first element in the iterable.
no setter
first → T: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns the first element in the set.
no setter
firstOrNull → T?: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns the first element in the iterable, or null if the iterable is empty.
no setter
firstOrNull → T?: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns the first element in the set, or null if the set is empty.
no setter
hashCode → int: The hash code for this object.
no setterinherited
hasListeners → bool: Indicates whether this VN has active listeners.
no setteroverride
isEmpty → bool: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns true if the iterable has no elements.
no setter
isEmpty → bool: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Returns true if the map has no key-value pairs.
no setter
isEmpty → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns true if the set has no elements.
no setter
isNotEmpty → bool: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns true if the iterable has one or more elements.
no setter
isNotEmpty → bool: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Returns true if the map has one or more key-value pairs.
no setter
isNotEmpty → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns true if the set has one or more elements.
no setter
keys → Iterable<K>: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Returns an iterable of all keys in the map.
no setter
last → T: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns the last element in the iterable.
no setter
last → T: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns the last element in the set.
no setter
lastOrNull → T?: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns the last element in the iterable, or null if the iterable is empty.
no setter
lastOrNull → T?: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns the last element in the set, or null if the set is empty.
no setter
length → int: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns the number of elements in the iterable.
no setter
length → int: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Returns the number of key-value pairs in the map.
no setter
length → int: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns the number of elements in the set.
no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
value ↔ T: Gets the current value of this VN.
getter/setter pairoverride-getter
values → Iterable<V>: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Returns an iterable of all values in the map.
no setter

Methods

add(T value) → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Adds the given value to the set.
addAll(Iterable<T> values) → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Adds all elements from the given values to the set.
addListener(VoidCallback listener) → void: Register a closure to be called when the object changes.
inherited
clear() → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes all elements from the set.
clear() → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes all key-value pairs from the map.
dispose() → void: Discards any resources used by the object. After this is called, the object is not in a usable state and should be discarded (calls to addListener will throw after the object is disposed).
inherited
firstWhere(bool function(T function)) → T: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns the first element that satisfies the given predicate function.
firstWhere(bool function(T)) → T: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns the first element that satisfies the given predicate function.
hardAdd(T value) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Adds the given value to the list and notifies listeners.
hardAddAll(Iterable<T> value) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Appends all elements from the given iterable value to the list and notifies listeners.
hardClear() → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes all elements from the set and notifies listeners.
hardClear() → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes all key-value pairs from the map and notifies listeners.
hardRemove(Object? value) → bool: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes the first occurrence of the given value from the list and notifies listeners.
hardRemove(Object? value) → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes the given value from the set and notifies listeners.
hardRemove(K key) → V?: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes the key-value pair with the given key from the map and notifies listeners.
hardRemoveAt(int index) → T: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes the element at the specified index from the list and notifies listeners.
hardRemoveWhere(bool where(T)) → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes all elements from the set that satisfy the predicate where and notifies listeners.
hardRemoveWhere(bool where(K key, V value)) → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes all key-value pairs from the map that satisfy the predicate where and notifies listeners.
hardRemoveWhere(bool where(T)) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes all elements that satisfy the given predicate where and notifies listeners.
hardSet(T newValue) → void: Updates the value and notifies listeners unconditionally.
lastWhere(bool function(T function)) → T: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns the last element that satisfies the given predicate function.
lastWhere(bool function(T)) → T: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns the last element that satisfies the given predicate function.
map<K2, V2>(MapEntry<K2, V2> converter(K k, V v)) → Map<K2, V2>: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Transforms the map by applying a function to all its key-value pairs.
map<R>(R map(T e)) → Iterable<R>: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Transforms the set by applying a function to all its elements.
merge<K, R>(VN<R> other, K initialValue, void listener(T left, R right, void emitter(K value))) → VN<K>: Merges this VN with another VN into a derived VN.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
notify() → void: Notifies all listeners about a change in value.
notifyListeners() → void: Call all the registered listeners.
inherited
remove(K key) → V?: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes the key-value pair with the given key from the map.
remove(Object? value) → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes the given value from the set.
removeListener(VoidCallback listener) → void: Remove a previously registered closure from the list of closures that are notified when the object changes.
inherited
removeWhere(bool where(K key, V value)) → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes all key-value pairs from the map that satisfy the given predicate where.
removeWhere(bool where(T)) → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes all elements from the set that satisfy the given predicate where.
silentAdd(T value) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Adds the given value to the list without notifying listeners.
silentAdd(T value) → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Adds the given value to the set without notifying listeners.
silentAddAll(Iterable<T> value) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Appends all elements from the given iterable value to the list without notifying listeners.
silentAddAll(Iterable<T> values) → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Adds all elements from the given values to the set without notifying listeners.
silentClear() → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes all key-value pairs from the map without notifying listeners.
silentClear() → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes all elements from the set without notifying listeners.
silentRemove(Object? value) → bool: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes the first occurrence of the given value from the list without notifying listeners.
silentRemove(Object? value) → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes the given value from the set without notifying listeners.
silentRemove(K key) → V?: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes the key-value pair with the given key from the map without notifying listeners.
silentRemoveAt(int index) → T: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes the element at the specified index from the list without notifying listeners.
silentRemoveWhere(bool where(T)) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes all elements that satisfy the given predicate where without notifying listeners.
silentRemoveWhere(bool where(K key, V value)) → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes all key-value pairs from the map that satisfy the predicate where without notifying listeners.
silentRemoveWhere(bool where(T)) → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes all elements from the set that satisfy the predicate where without notifying listeners.
silentSet(T newValue) → void: Updates the value without notifying listeners.
smartAdd(T value) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Adds the given value to the list, with behavior determined by ChangeType.
smartAdd(T value) → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Adds the given value to the set and notifies listeners if the value was added.
smartAddAll(Iterable<T> value) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Appends all elements from the given iterable value to the list, with behavior determined by ChangeType.
smartAddAll(Iterable<T> values) → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Adds all elements from the given values to the set and notifies listeners if the set changed.
smartClear() → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes all key-value pairs from the map, with behavior determined by ChangeType.
smartClear() → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes all elements from the set and notifies listeners if the set was not empty.
smartRemove(Object? value) → bool: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes the first occurrence of the given value from the list, with behavior determined by ChangeType.
smartRemove(K key) → V?: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes the key-value pair with the given key from the map, with behavior determined by ChangeType.
smartRemove(Object? value) → bool: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes the given value from the set and notifies listeners if the set changed.
smartRemoveAt(int index) → T: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes the element at the specified index from the list, with behavior determined by ChangeType.
smartRemoveWhere(bool where(T)) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Removes all elements that satisfy the given predicate where, with behavior determined by ChangeType.
smartRemoveWhere(bool where(T)) → void: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Removes all elements from the set that satisfy the predicate where, with behavior determined by ChangeType.
smartRemoveWhere(bool where(K key, V value)) → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Removes all key-value pairs from the map that satisfy the predicate where, with behavior determined by ChangeType.
smartSet(T newValue) → void: Updates the value if it differs from the current value, and notifies listeners.
toList() → List<T>: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns a new list containing all elements of the iterable.
toString() → String: Returns a string representation of this VN.
override
where(bool function(T function)) → Iterable<T>: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Returns a new lazy Iterable with all elements that satisfy the predicate function.
where(bool function(T)) → Iterable<T>: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Returns a new lazy Iterable with all elements that satisfy the predicate function.

Operators

operator ==(Object other) → bool: The equality operator.
inherited
operator [](int index) → T: Available on VN<Iterable<T>>, provided by the BetterIterableNotifications extension
Gets the element at the specified index in the iterable.
operator [](int index) → T: Available on VN<List<T>>, provided by the BetterListNotifications extension
Gets the element at the specified index in the list.
operator [](K key) → V?: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Retrieves the value associated with the given key in the map.
operator [](int index) → T: Available on VN<Set<T>>, provided by the BetterSetNotifications extension
Retrieves the element at the specified index in the set.
operator []=(int index, T value) → void: Available on VN<List<T>>, provided by the BetterListNotifications extension
Sets the element at the specified index in the list to the given value.
operator []=(K key, V value) → void: Available on VN<Map<K, V>>, provided by the BetterMapNotifications extension
Associates the given key with the given value in the map.

Static Methods

merged<T, L, R>(T initialValue, {required VN<L> left, required VN<R> right, required void listener(L left, R right, void emitter(T value)), ChangeType? changeType, void whenDispose()?}) → VN<T>: Factory method for creating a merged VN.