ListBase<E> class abstract mixin

Abstract implementation of a list.

ListBase can be used as a base class for implementing the List interface.

This class implements all read operations using only the length and operator[] and members. It implements write operations using those and add, length= and operator[]= Classes using this base class should implement those five operations.

NOTICE: For backwards compatibility reasons, there is a default implementation of add which only works for lists with a nullable element type. For list with a non-nullable element type, the add method must be implemented.

NOTICE: Forwarding just the four length and [] read/write operations to a normal growable List (as created by a [] literal) will give very bad performance for add and addAll operations of ListBase. These operations are implemented by increasing the length of the list by one for each add operation, and repeatedly increasing the length of a growable list is not efficient. To avoid this, override 'add' and 'addAll' to also forward directly to the growable list, or, if possible, use DelegatingList from "package:collection/collection.dart" instead of a ListMixin.

Implemented types

List<E>

Implementers

Available extensions

Constructors

ListBase(): const

Properties

average → double: Available on Iterable<int>, provided by the IterableIntegerExtension extension
The arithmetic mean of the elements of a non-empty iterable.
no setter
average → double: Available on Iterable<num>, provided by the IterableNumberExtension extension
The arithmetic mean of the elements of a non-empty iterable.
no setter
first ↔ E: The first element.
getter/setter pairoverride
firstOrNull → T?: Available on Iterable<T>, provided by the IterableExtension extension
The first element, or null if the iterable is empty.
no setter
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
flattened → Iterable<T>: Available on Iterable<Iterable<T>>, provided by the IterableIterableExtension extension
The sequential elements of each iterable in this iterable.
no setter
flattenedToList → List<T>: Available on Iterable<Iterable<T>>, provided by the IterableIterableExtension extension
The sequential elements of each iterable in this iterable.
no setter
flattenedToSet → Set<T>: Available on Iterable<Iterable<T>>, provided by the IterableIterableExtension extension
The unique sequential elements of each iterable in this iterable.
no setter
hashCode → int: The hash code for this object.
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 setteroverride
isNotEmpty → bool: Whether this collection has at least one element.
no setteroverride
iterator → Iterator<E>: A new Iterator that allows iterating the elements of this Iterable.
no setteroverride
last ↔ E: The last element.
getter/setter pairoverride
lastOrNull → T?: Available on Iterable<T>, provided by the IterableExtension extension
The last element, or null if the iterable is empty.
no setter
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 objects in this list.
getter/setter pairinherited
max → num: Available on Iterable<num>, provided by the IterableNumberExtension extension
A maximal element of the iterable.
no setter
max → T: Available on Iterable<T>, provided by the IterableComparableExtension extension
A maximal element of the iterable.
no setter
max → double: Available on Iterable<double>, provided by the IterableDoubleExtension extension
A maximal element of the iterable.
no setter
max → int: Available on Iterable<int>, provided by the IterableIntegerExtension extension
A maximal element of the iterable.
no setter
maxOrNull → int?: Available on Iterable<int>, provided by the IterableIntegerExtension extension
A maximal element of the iterable, or null if the iterable is empty.
no setter
maxOrNull → double?: Available on Iterable<double>, provided by the IterableDoubleExtension extension
A maximal element of the iterable, or null if the iterable is empty.
no setter
maxOrNull → T?: Available on Iterable<T>, provided by the IterableComparableExtension extension
A maximal element of the iterable, or null if the iterable is empty.
no setter
maxOrNull → num?: Available on Iterable<num>, provided by the IterableNumberExtension extension
A maximal element of the iterable, or null if the iterable is empty.
no setter
min → num: Available on Iterable<num>, provided by the IterableNumberExtension extension
A minimal element of the iterable.
no setter
min → double: Available on Iterable<double>, provided by the IterableDoubleExtension extension
A minimal element of the iterable.
no setter
min → int: Available on Iterable<int>, provided by the IterableIntegerExtension extension
A minimal element of the iterable.
no setter
min → T: Available on Iterable<T>, provided by the IterableComparableExtension extension
A minimal element of the iterable.
no setter
minOrNull → num?: Available on Iterable<num>, provided by the IterableNumberExtension extension
A minimal element of the iterable, or null it the iterable is empty.
no setter
minOrNull → T?: Available on Iterable<T>, provided by the IterableComparableExtension extension
A minimal element of the iterable, or null it the iterable is empty.
no setter
minOrNull → int?: Available on Iterable<int>, provided by the IterableIntegerExtension extension
A minimal element of the iterable, or null it the iterable is empty.
no setter
minOrNull → double?: Available on Iterable<double>, provided by the IterableDoubleExtension extension
A minimal element of the iterable, or null it the iterable is empty.
no setter
nonNulls → Iterable<T>: Available on Iterable<T?>, provided by the NullableIterableExtensions extension
The non-null elements of this iterable.
no setter
reversed → Iterable<E>: An Iterable of the objects in this list in reverse order.
no setteroverride
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
single → E: Checks that this iterable has only one element, and returns that element.
no setteroverride
singleOrNull → T?: Available on Iterable<T>, provided by the IterableExtensions extension
The single element of this iterator, or null.
no setter
singleOrNull → T?: Available on Iterable<T>, provided by the IterableExtension extension
The single element of the iterable, or null.
no setter
sum → double: Available on Iterable<double>, provided by the IterableDoubleExtension extension
The sum of the elements.
no setter
sum → num: Available on Iterable<num>, provided by the IterableNumberExtension extension
The sum of the elements.
no setter
sum → int: Available on Iterable<int>, provided by the IterableIntegerExtension extension
The sum of the elements.
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
wait → Future<List<T>>: Available on Iterable<Future<T>>, provided by the FutureIterable extension
Waits for futures in parallel.
no setter

Methods

add(E element) → void: Adds value to the end of this list, extending the length by one.
override
addAll(Iterable<E> iterable) → void: Appends all objects of iterable to the end of this list.
override
any(bool test(E element)) → bool: Checks whether any element of this iterable satisfies test.
override
asMap() → Map<int, E>: An unmodifiable Map view of this list.
override
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.
binarySearch(E element, [int compare(E, E)?]) → int: Available on List<E>, provided by the ListComparableExtensions extension
Returns the index of element in this sorted list.
binarySearch(E element, int compare(E, E)) → int: Available on List<E>, provided by the ListExtensions extension
Returns the index of element in this sorted list.
binarySearchBy<K extends Comparable<K>>(E element, K keyOf(E element), [int start = 0, int? end]) → int: Available on List<E>, provided by the ListExtensions extension
Returns the index of element in this sorted list.
binarySearchByCompare<K>(E element, K keyOf(E element), int compare(K, K), [int start = 0, int? end]) → int: Available on List<E>, provided by the ListExtensions extension
Returns the index of element in this sorted list.
byName(String name) → T: Available on Iterable<T>, provided by the EnumByName extension
Finds the enum value in this list with name name.
cast<R>() → List<R>: Returns a view of this list as a list of R instances.
override
clear() → void: Removes all objects from this list; the length of the list becomes zero.
override
contains(Object? element) → bool: Whether the collection contains an element equal to element.
override
elementAt(int index) → E: Returns the indexth element.
override
elementAtOrNull(int index) → E?: Available on List<E>, provided by the ListExtensions extension
The indexth element, or null if there is no such element.
elementAtOrNull(int index) → T?: Available on Iterable<T>, provided by the IterableExtensions extension
The element at position index of this iterable, or null.
elementAtOrNull(int index) → T?: Available on Iterable<T>, provided by the IterableExtension extension
The indexth element, or null if there is no such element.
equals(List<E> other, [Equality<E> equality = const DefaultEquality()]) → bool: Available on List<E>, provided by the ListExtensions extension
Whether other has the same elements as this list.
every(bool test(E element)) → bool: Checks whether every element of this iterable satisfies test.
override
expand<T>(Iterable<T> f(E element)) → Iterable<T>: Expands each element of this Iterable into zero or more elements.
override
expandIndexed<R>(Iterable<R> expand(int index, E element)) → Iterable<R>: Available on List<E>, provided by the ListExtensions extension
Expands each element and index to a number of elements in a new iterable.
expandIndexed<R>(Iterable<R> expand(int index, T element)) → Iterable<R>: Available on Iterable<T>, provided by the IterableExtension extension
Expands each element and index to a number of elements in a new iterable.
fillRange(int start, int end, [E? fill]) → void: Overwrites a range of elements with fillValue.
override
firstWhere(bool test(E element), {E orElse()?}) → E: The first element that satisfies the given predicate test.
override
firstWhereIndexedOrNull(bool test(int index, T element)) → T?: Available on Iterable<T>, provided by the IterableExtension extension
The first element whose value and index satisfies test.
firstWhereOrNull(bool test(T element)) → T?: Available on Iterable<T>, provided by the IterableExtension extension
The first element satisfying test, or null if there are none.
fold<T>(T initialValue, T combine(T previousValue, E element)) → T: Reduces a collection to a single value by iteratively combining each element of the collection with an existing value
override
foldIndexed<R>(R initialValue, R combine(int index, R previous, T element)) → R: Available on Iterable<T>, provided by the IterableExtension extension
Combine the elements with a value and the current index.
followedBy(Iterable<E> other) → Iterable<E>: Creates the lazy concatenation of this iterable and other.
override
forEach(void action(E element)) → void: Invokes action on each element of this iterable in iteration order.
override
forEachIndexed(void action(int index, T element)) → void: Available on Iterable<T>, provided by the IterableExtension extension
Takes an action for each element.
forEachIndexed(void action(int index, E element)) → void: Available on List<E>, provided by the ListExtensions extension
Takes an action for each element.
forEachIndexedWhile(bool action(int index, E element)) → void: Available on List<E>, provided by the ListExtensions extension
Takes an action for each element and index as long as desired.
forEachIndexedWhile(bool action(int index, T element)) → void: Available on Iterable<T>, provided by the IterableExtension extension
Takes an action for each element and index as long as desired.
forEachWhile(bool action(E element)) → void: Available on List<E>, provided by the ListExtensions extension
Takes an action for each element as long as desired.
forEachWhile(bool action(T element)) → void: Available on Iterable<T>, provided by the IterableExtension extension
Takes an action for each element as long as desired.
getRange(int start, int end) → Iterable<E>: Creates an Iterable that iterates over a range of elements.
override
groupFoldBy<K, G>(K keyOf(T element), G combine(G? previous, T element)) → Map<K, G>: Available on Iterable<T>, provided by the IterableExtension extension
Groups elements by keyOf then folds the elements in each group.
groupListsBy<K>(K keyOf(T element)) → Map<K, List<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Groups elements into lists by keyOf.
groupSetsBy<K>(K keyOf(T element)) → Map<K, Set<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Groups elements into sets by keyOf.
indexOf(Object? element, [int start = 0]) → int: The first index of element in this list.
override
indexWhere(bool test(E element), [int start = 0]) → int: The first index in the list that satisfies the provided test.
override
insert(int index, E element) → void: Inserts element at position index in this list.
override
insertAll(int index, Iterable<E> iterable) → void: Inserts all objects of iterable at position index in this list.
override
isSorted(Comparator<T> compare) → bool: Available on Iterable<T>, provided by the IterableExtension extension
Whether the elements are sorted by the compare ordering.
isSorted([Comparator<T>? compare]) → bool: Available on Iterable<T>, provided by the IterableComparableExtension extension
Whether the elements are sorted by the compare ordering.
isSortedBy<K extends Comparable<K>>(K keyOf(T element)) → bool: Available on Iterable<T>, provided by the IterableExtension extension
Whether the elements are sorted by their keyOf property.
isSortedByCompare<K>(K keyOf(T element), Comparator<K> compare) → bool: Available on Iterable<T>, provided by the IterableExtension extension
Whether the elements are compare-sorted by their keyOf property.
join([String separator = ""]) → String: Converts each element to a String and concatenates the strings.
override
lastBy<K>(K key(T)) → Map<K, T>: Available on Iterable<T>, provided by the IterableExtension extension
Associates the elements in this by the value returned by key.
lastIndexOf(Object? element, [int? start]) → int: The last index of element in this list.
override
lastIndexWhere(bool test(E element), [int? start]) → int: The last index in the list that satisfies the provided test.
override
lastWhere(bool test(E element), {E orElse()?}) → E: The last element that satisfies the given predicate test.
override
lastWhereIndexedOrNull(bool test(int index, T element)) → T?: Available on Iterable<T>, provided by the IterableExtension extension
The last element whose index and value satisfies test.
lastWhereOrNull(bool test(T element)) → T?: Available on Iterable<T>, provided by the IterableExtension extension
The last element satisfying test, or null if there are none.
lowerBound(E element, [int compare(E, E)?]) → int: Available on List<E>, provided by the ListComparableExtensions extension
Returns the index where element should be in this sorted list.
lowerBound(E element, int compare(E, E)) → int: Available on List<E>, provided by the ListExtensions extension
Returns the index where element should be in this sorted list.
lowerBoundBy<K extends Comparable<K>>(E element, K keyOf(E), [int start = 0, int? end]) → int: Available on List<E>, provided by the ListExtensions extension
Returns the index where element should be in this sorted list.
lowerBoundByCompare<K>(E element, K keyOf(E), int compare(K, K), [int start = 0, int? end]) → int: Available on List<E>, provided by the ListExtensions extension
Returns the index where element should be in this sorted list.
map<T>(T f(E element)) → Iterable<T>: The current elements of this iterable modified by toElement.
override
mapIndexed<R>(R convert(int index, T element)) → Iterable<R>: Available on Iterable<T>, provided by the IterableExtension extension
Maps each element and its index to a new value.
mapIndexed<R>(R convert(int index, E element)) → Iterable<R>: Available on List<E>, provided by the ListExtensions extension
Maps each element and its index to a new value.
none(bool test(T)) → bool: Available on Iterable<T>, provided by the IterableExtension extension
Whether no element satisfies test.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
reduce(E combine(E previousValue, E element)) → E: Reduces a collection to a single value by iteratively combining elements of the collection using the provided function.
override
reduceIndexed(T combine(int index, T previous, T element)) → T: Available on Iterable<T>, provided by the IterableExtension extension
Combine the elements with each other and the current index.
remove(Object? element) → bool: Removes the first occurrence of value from this list.
override
removeAt(int index) → E: Removes the object at position index from this list.
override
removeLast() → E: Removes and returns the last object in this list.
override
removeRange(int start, int end) → void: Removes a range of elements from the list.
override
removeWhere(bool test(E element)) → void: Removes all objects from this list that satisfy test.
override
replaceRange(int start, int end, Iterable<E> newContents) → void: Replaces a range of elements with the elements of replacements.
override
retainWhere(bool test(E element)) → void: Removes all objects from this list that fail to satisfy test.
override
reverseRange(int start, int end) → void: Available on List<E>, provided by the ListExtensions extension
Reverses the elements in a range of the list.
sample(int count, [Random? random]) → List<T>: Available on Iterable<T>, provided by the IterableExtension extension
Selects count elements at random from this iterable.
setAll(int index, Iterable<E> iterable) → void: Overwrites elements with the objects of iterable.
override
setRange(int start, int end, Iterable<E> iterable, [int skipCount = 0]) → void: Writes some elements of iterable into a range of this list.
override
shuffle([Random? random]) → void: Shuffles the elements of this list randomly.
override
shuffled([Random? random]) → List<T>: Available on Iterable<T>, provided by the IterableExtension extension
Creates a shuffled list of the elements of the iterable.
shuffleRange(int start, int end, [Random? random]) → void: Available on List<E>, provided by the ListExtensions extension
Shuffle a range of elements.
singleWhere(bool test(E element), {E orElse()?}) → E: The single element that satisfies test.
override
singleWhereIndexedOrNull(bool test(int index, T element)) → T?: Available on Iterable<T>, provided by the IterableExtension extension
The single element satisfying test.
singleWhereOrNull(bool test(T element)) → T?: Available on Iterable<T>, provided by the IterableExtension extension
The single element satisfying test.
skip(int count) → Iterable<E>: Creates an Iterable that provides all but the first count elements.
override
skipWhile(bool test(E element)) → Iterable<E>: Creates an Iterable that skips leading elements while test is satisfied.
override
slice(int start, [int? end]) → ListSlice<E>: Available on List<E>, provided by the ListExtensions extension
A fixed length view of a range of this list.
slices(int length) → Iterable<List<E>>: Available on List<E>, provided by the ListExtensions extension
Contiguous slices of this with the given length.
slices(int length) → Iterable<List<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Contiguous slices of this with the given length.
sort([int compare(E a, E b)?]) → void: Sorts this list according to the order specified by the compare function.
override
sortBy<K extends Comparable<K>>(K keyOf(E element), [int start = 0, int? end]) → void: Available on List<E>, provided by the ListExtensions extension
Sorts elements by the natural order of their keyOf property.
sortByCompare<K>(K keyOf(E element), int compare(K a, K b), [int start = 0, int? end]) → void: Available on List<E>, provided by the ListExtensions extension
Sorts elements by the compare of their keyOf property.
sorted(Comparator<T> compare) → List<T>: Available on Iterable<T>, provided by the IterableExtension extension
Creates a sorted list of the elements of the iterable.
sorted([Comparator<T>? compare]) → List<T>: Available on Iterable<T>, provided by the IterableComparableExtension extension
Creates a sorted list of the elements of the iterable.
sortedBy<K extends Comparable<K>>(K keyOf(T element)) → List<T>: Available on Iterable<T>, provided by the IterableExtension extension
Creates a sorted list of the elements of the iterable.
sortedByCompare<K>(K keyOf(T element), Comparator<K> compare) → List<T>: Available on Iterable<T>, provided by the IterableExtension extension
Creates a sorted list of the elements of the iterable.
sortRange(int start, int end, int compare(E a, E b)) → void: Available on List<E>, provided by the ListExtensions extension
Sort a range of elements by compare.
sortRange(int start, int end, [int compare(E a, E b)?]) → void: Available on List<E>, provided by the ListComparableExtensions extension
Sort a range of elements by compare.
splitAfter(bool test(T element)) → Iterable<List<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Splits the elements into chunks after some elements.
splitAfterIndexed(bool test(int index, T element)) → Iterable<List<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Splits the elements into chunks after some elements and indices.
splitBefore(bool test(T element)) → Iterable<List<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Splits the elements into chunks before some elements.
splitBeforeIndexed(bool test(int index, T element)) → Iterable<List<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Splits the elements into chunks before some elements and indices.
splitBetween(bool test(T first, T second)) → Iterable<List<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Splits the elements into chunks between some elements.
splitBetweenIndexed(bool test(int index, T first, T second)) → Iterable<List<T>>: Available on Iterable<T>, provided by the IterableExtension extension
Splits the elements into chunks between some elements and indices.
sublist(int start, [int? end]) → List<E>: Returns a new list containing the elements between start and end.
override
swap(int index1, int index2) → void: Available on List<E>, provided by the ListExtensions extension
Swaps two elements of this list.
take(int count) → Iterable<E>: Creates a lazy iterable of the count first elements of this iterable.
override
takeWhile(bool test(E element)) → Iterable<E>: Creates a lazy iterable of the leading elements satisfying test.
override
toList({bool growable = true}) → List<E>: Creates a List containing the elements of this Iterable.
override
toSet() → Set<E>: Creates a Set containing the same elements as this iterable.
override
toString() → String: A string representation of this object.
override
where(bool test(E element)) → Iterable<E>: Creates a new lazy Iterable with all elements that satisfy the predicate test.
override
whereIndexed(bool test(int index, T element)) → Iterable<T>: Available on Iterable<T>, provided by the IterableExtension extension
The elements whose value and index satisfies test.
whereIndexed(bool test(int index, E element)) → Iterable<E>: Available on List<E>, provided by the ListExtensions extension
The elements whose value and index satisfies test.
whereNot(bool test(T element)) → Iterable<T>: Available on Iterable<T>, provided by the IterableExtension extension
The elements that do not satisfy test.
whereNotIndexed(bool test(int index, T element)) → Iterable<T>: Available on Iterable<T>, provided by the IterableExtension extension
The elements whose value and index do not satisfy test.
whereNotIndexed(bool test(int index, E element)) → Iterable<E>: Available on List<E>, provided by the ListExtensions extension
The elements whose value and index do not satisfy test.
whereNotNull() → Iterable<T>: Available on Iterable<T?>, provided by the IterableNullableExtension extension
The non-null elements of this Iterable.
whereType<T>() → Iterable<T>: Creates a new lazy Iterable with all elements that have type T.
override

Operators

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

Static Methods

listToString(List<Object?> list) → String: Converts a List to a String.