ListNotifier<T> class

A List that behaves like ValueNotifier if its data changes.

Notification Modes

CustomNotifierMode.normal: Listeners are only notified when a value actually changes. For example, setting an index to the same value it already has will not notify listeners. No-op operations (like removing a non-existent value) also won't notify.
CustomNotifierMode.always: Listeners are notified on every operation, even if the value doesn't change. This ensures UI always updates when operations are attempted.
CustomNotifierMode.manual: No automatic notifications. You must call notifyListeners manually after making changes.

Bulk Operations

Two categories of bulk operations:

Append/Insert operations (addAll, insertAll, setAll, setRange): Always notify listeners, even with empty input, regardless of notification mode (except manual).
Replace operations (fillRange, replaceRange): Compare values in normal mode and only notify if changes occurred.

Transactions

Use startTransAction and endTransAction to batch multiple operations into a single notification. This is useful for atomic updates.

Implemented types

Mixed-in types

ChangeNotifier

Available extensions

Constructors

ListNotifier({List<T>? data, CustomNotifierMode notificationMode = CustomNotifierMode.always, bool customEquality(T x, T y)?}): Creates a new listenable List data optional list that should be used as initial value. notificationMode determines whether to notify listeners if an equal value is assigned. If set to CustomNotifierMode.normal, ListNotifier will compare if a value passed is equal to the existing value (e.g., list[5]=4 will only call notifyListeners if the content at index 5 is not equal to 4). To prevent users from wondering why their UI doesn't update if they haven't overridden the equality operator, the default is CustomNotifierMode.always. customEquality can be used to set your own criteria for comparing when notificationMode is set to CustomNotifierMode.normal.

Properties

customEquality → bool Function(T x, T y)?: final
first ↔ T: The first element.
getter/setter pairinherited
firstOrNull → T?: Available on Iterable<T>, provided by the IterableExtensions extension
The first element of this iterator, or null if the iterable is empty.
no setter
hashCode → int: The hash code for this object.
no setterinherited
hasListeners → bool: Whether any listeners are currently registered.
no setterinherited
indexed → Iterable<(int, T)>: Available on Iterable<T>, provided by the IterableExtensions extension
Pairs of elements of the indices and elements of this iterable.
no setter
isEmpty → bool: Whether this collection has no elements.
no setterinherited
isNotEmpty → bool: Whether this collection has at least one element.
no setterinherited
iterator → Iterator<T>: A new Iterator that allows iterating the elements of this Iterable.
no setterinherited
last ↔ T: The last element.
getter/setter pairinherited
lastOrNull → T?: Available on Iterable<T>, provided by the IterableExtensions extension
The last element of this iterable, or null if the iterable is empty.
no setter
length ↔ int: The number of elements in this Iterable.
getter/setter pairinherited-getter
nonNulls → Iterable<T>: Available on Iterable<T?>, provided by the NullableIterableExtensions extension
The non-null elements of this iterable.
no setter
reversed → Iterable<T>: An Iterable of the objects in this list in reverse order.
no setterinherited
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
single → T: Checks that this iterable has only one element, and returns that element.
no setterinherited
singleOrNull → T?: Available on Iterable<T>, provided by the IterableExtensions extension
The single element of this iterator, or null.
no setter
toJS → JSArray<T>: Available on List<T>, provided by the ListToJSArray extension
Converts this List to a JSArray by either casting, unwrapping, or cloning the List.
no setter
toJSProxyOrRef → JSArray<T>: Available on List<T>, provided by the ListToJSArray extension
Converts this List to a JSArray by either casting, unwrapping, or proxying the List.
no setter
value → List<T>: Returns an immutable view of the current list state.
no setteroverride
wait → Future<List<T>>: Available on Iterable<Future<T>>, provided by the FutureIterable extension
Waits for futures in parallel.
no setter

Methods

add(T value) → void: Adds value to the end of this list, extending the length by one.
addAll(Iterable<T> iterable) → void: Appends all objects of iterable to the end of this list.
addListener(VoidCallback listener) → void: Register a closure to be called when the object changes.
inherited
any(bool test(T)) → bool: Checks whether any element of this iterable satisfies test.
inherited
asMap() → Map<int, T>: An unmodifiable Map view of this list.
inherited
asNameMap() → Map<String, T>: Available on Iterable<T>, provided by the EnumByName extension
Creates a map from the names of enum values to the values.
byName(String name) → T: Available on Iterable<T>, provided by the EnumByName extension
Finds the enum value in this list with name name.
cast<T>() → List<T>: A view of this iterable as an iterable of R instances.
inherited
clear() → void: Removes all objects from this list; the length of the list becomes zero.
contains(Object? element) → bool: Whether the collection contains an element equal to element.
inherited
debounce(Duration timeOut) → Listenable: Available on Listenable, provided by the FunctionaListener2 extension
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
elementAt(int index) → T: Returns the indexth element.
inherited
elementAtOrNull(int index) → T?: Available on Iterable<T>, provided by the IterableExtensions extension
The element at position index of this iterable, or null.
endTransAction({bool notify = true}) → void: Ends a transaction
every(bool test(T)) → bool: Checks whether every element of this iterable satisfies test.
inherited
expand<T>(Iterable<T> f(T)) → Iterable<T>: Expands each element of this Iterable into zero or more elements.
inherited
fillRange(int start, int end, [T? fillValue]) → void: Overwrites a range of elements with fillValue.
firstWhere(bool test(T), {T orElse()?}) → T: The first element that satisfies the given predicate test.
inherited
fold<T>(T initialValue, T combine(T previousValue, T element)) → T: Reduces a collection to a single value by iteratively combining each element of the collection with an existing value
inherited
followedBy(Iterable<T> other) → Iterable<T>: Creates the lazy concatenation of this iterable and other.
inherited
forEach(void f(T)) → void: Invokes action on each element of this iterable in iteration order.
inherited
getRange(int start, int end) → Iterable<T>: Creates an Iterable that iterates over a range of elements.
inherited
indexOf(T element, [int start = 0]) → int: The first index of element in this list.
inherited
indexWhere(bool test(T), [int start = 0]) → int: The first index in the list that satisfies the provided test.
inherited
insert(int index, T element) → void: Inserts element at position index in this list.
insertAll(int index, Iterable<T> iterable) → void: Inserts all objects of iterable at position index in this list.
join([String separator = '']) → String: Converts each element to a String and concatenates the strings.
inherited
lastIndexOf(T element, [int? start]) → int: The last index of element in this list.
inherited
lastIndexWhere(bool test(T), [int? start]) → int: The last index in the list that satisfies the provided test.
inherited
lastWhere(bool test(T), {T orElse()?}) → T: The last element that satisfies the given predicate test.
inherited
listen(void handler(ListenableSubscription)) → ListenableSubscription: Available on Listenable, provided by the FunctionaListener2 extension
let you work with a Listenable as it should be by installing a handler function that is called on any value change of this and gets the new value passed as an argument. It returns a subscription object that lets you stop the handler from being called by calling cancel() on the subscription. The handler get the subscription object passed on every call so that it is possible to uninstall the handler from the handler itself.
map<T>(T f(T)) → Iterable<T>: The current elements of this iterable modified by toElement.
inherited
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
notifyListeners() → void: If needed you can notifiy all listeners manually
override
reduce(T combine(T value, T element)) → T: Reduces a collection to a single value by iteratively combining elements of the collection using the provided function.
inherited
remove(Object? value) → bool: Removes the first occurrence of value from this list.
removeAt(int index) → T: Removes the object at position index from this list.
removeLast() → T: Removes and returns the last object in this list.
removeListener(VoidCallback listener) → void: Remove a previously registered closure from the list of closures that are notified when the object changes.
inherited
removeRange(int start, int end) → void: Removes a range of elements from the list.
removeWhere(bool test(T)) → void: Removes all objects from this list that satisfy test.
replaceRange(int start, int end, Iterable<T> iterable) → void: Replaces a range of elements with the elements of replacements.
retainWhere(bool test(T)) → void: Removes all objects from this list that fail to satisfy test.
retype<T>() → List<T>: inherited
setAll(int index, Iterable<T> iterable) → void: Overwrites elements with the objects of iterable.
setRange(int start, int end, Iterable<T> iterable, [int skipCount = 0]) → void: Writes some elements of iterable into a range of this list.
shuffle([Random? random]) → void: Shuffles the elements of this list randomly.
singleWhere(bool test(T), {T orElse()?}) → T: The single element that satisfies test.
inherited
skip(int n) → Iterable<T>: Creates an Iterable that provides all but the first count elements.
inherited
skipWhile(bool test(T)) → Iterable<T>: Creates an Iterable that skips leading elements while test is satisfied.
inherited
sort([int compare(T, T)?]) → void: Sorts this list according to the order specified by the compare function.
startTransAction() → void: Starts a transaction that allows to make multiple changes to the List with only one notification at the end.
sublist(int start, [int? end]) → List<T>: Returns a new list containing the elements between start and end.
inherited
swap(int index1, int index2) → void: Swaps elements at index1 with index2.
take(int n) → Iterable<T>: Creates a lazy iterable of the count first elements of this iterable.
inherited
takeWhile(bool test(T)) → Iterable<T>: Creates a lazy iterable of the leading elements satisfying test.
inherited
toList({bool growable = true}) → List<T>: Creates a List containing the elements of this Iterable.
inherited
toSet() → Set<T>: Creates a Set containing the same elements as this iterable.
inherited
toString() → String: A string representation of this object.
inherited
where(bool test(T)) → Iterable<T>: Creates a new lazy Iterable with all elements that satisfy the predicate test.
inherited
whereType<T>() → Iterable<T>: Creates a new lazy Iterable with all elements that have type T.
inherited

Operators

operator +(List<T> other) → List<T>: Returns the concatenation of this list and other.
inherited
operator ==(Object other) → bool: The equality operator.
inherited
operator [](int index) → T: The object at the given index in the list.
operator []=(int index, T value) → void: Sets the value at the given index in the list to value.