ListBase<E> class

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

first ↔ E: The first element.
read / writeoverride
hashCode → int: The hash code for this object.
read-onlyinherited
isEmpty → bool: Whether this collection has no elements.
read-onlyoverride
isNotEmpty → bool: Whether this collection has at least one element.
read-onlyoverride
iterator → Iterator<E>: A new Iterator that allows iterating the elements of this Iterable.
read-onlyoverride
last ↔ E: The last element.
read / writeoverride
length ↔ int: The number of objects in this list.
read / writeinherited
reversed → Iterable<E>: An Iterable of the objects in this list in reverse order.
read-onlyoverride
runtimeType → Type: A representation of the runtime type of the object.
read-onlyinherited
single → E: Checks that this iterable has only one element, and returns that element.
read-onlyoverride

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
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
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
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
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
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
getRange(int start, int end) → Iterable<E>: Creates an Iterable that iterates over a range of elements.
override
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
join([String separator = ""]) → String: Converts each element to a String and concatenates the strings.
override
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
map<T>(T f(E element)) → Iterable<T>: The current elements of this iterable modified by toElement.
override
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
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
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
singleWhere(bool test(E element), {E orElse()?}) → E: The single element that satisfies test.
override
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
sort([int compare(E a, E b)?]) → void: Sorts this list according to the order specified by the compare function.
override
sublist(int start, [int? end]) → List<E>: Returns a new list containing the elements between start and end.
override
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
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.