ListBase<E> class Null safety

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.

Mixed in types
Implementers
Available Extensions

Constructors

ListBase()

Properties

first ↔ E
Returns the first element. [...]
read / write, inherited
hashCode int
The hash code for this object. [...]
read-only, inherited
isEmpty bool
Returns true if there are no elements in this collection. [...]
read-only, inherited
isNotEmpty bool
Returns true if there is at least one element in this collection. [...]
read-only, inherited
iterator Iterator<E>
Returns a new Iterator that allows iterating the elements of this Iterable. [...]
read-only, inherited
last ↔ E
Returns the last element. [...]
read / write, inherited
length int
The number of objects in this list. [...]
read / write, inherited
reversed Iterable<E>
An Iterable of the objects in this list in reverse order.
read-only, inherited
runtimeType Type
A representation of the runtime type of the object.
read-only, inherited
single → E
Checks that this iterable has only one element, and returns that element. [...]
read-only, inherited

Methods

add(E element) → void
Adds value to the end of this list, extending the length by one. [...]
inherited
addAll(Iterable<E> iterable) → void
Appends all objects of iterable to the end of this list. [...]
inherited
any(bool test(E element)) bool
Checks whether any element of this iterable satisfies test. [...]
inherited
asMap() Map<int, E>
An unmodifiable Map view of this list. [...]
inherited
cast<R>() List<R>
Returns a view of this list as a list of R instances. [...]
inherited
clear() → void
Removes all objects from this list; the length of the list becomes zero. [...]
inherited
contains(Object? element) bool
Whether the collection contains an element equal to element. [...]
inherited
elementAt(int index) → E
Returns the indexth element. [...]
inherited
every(bool test(E element)) bool
Checks whether every element of this iterable satisfies test. [...]
inherited
expand<T>(Iterable<T> f(E element)) Iterable<T>
Expands each element of this Iterable into zero or more elements. [...]
inherited
fillRange(int start, int end, [E? fill]) → void
Overwrites a range of elements with fillValue. [...]
inherited
firstWhere(bool test(E element), {E orElse()?}) → E
Returns the first element that satisfies the given predicate test. [...]
inherited
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 [...]
inherited
followedBy(Iterable<E> other) Iterable<E>
Returns the lazy concatenation of this iterable and other. [...]
inherited
forEach(void action(E element)) → void
Invokes action on each element of this iterable in iteration order.
inherited
getRange(int start, int end) Iterable<E>
Creates an Iterable that iterates over a range of elements. [...]
inherited
indexOf(Object? element, [int start = 0]) int
The first index of element in this list. [...]
inherited
indexWhere(bool test(E element), [int start = 0]) int
The first index in the list that satisfies the provided test. [...]
inherited
insert(int index, E element) → void
Inserts element at position index in this list. [...]
inherited
insertAll(int index, Iterable<E> iterable) → void
Inserts all objects of iterable at position index in this list. [...]
inherited
join([String separator = ""]) String
Converts each element to a String and concatenates the strings. [...]
inherited
lastIndexOf(Object? element, [int? start]) int
The last index of element in this list. [...]
inherited
lastIndexWhere(bool test(E element), [int? start]) int
The last index in the list that satisfies the provided test. [...]
inherited
lastWhere(bool test(E element), {E orElse()?}) → E
Returns the last element that satisfies the given predicate test. [...]
inherited
map<T>(T f(E element)) Iterable<T>
The current elements of this iterable modified by toElement. [...]
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent 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. [...]
inherited
remove(Object? element) bool
Removes the first occurrence of value from this list. [...]
inherited
removeAt(int index) → E
Removes the object at position index from this list. [...]
inherited
removeLast() → E
Removes and returns the last object in this list. [...]
inherited
removeRange(int start, int end) → void
Removes a range of elements from the list. [...]
inherited
removeWhere(bool test(E element)) → void
Removes all objects from this list that satisfy test. [...]
inherited
replaceRange(int start, int end, Iterable<E> newContents) → void
Replaces a range of elements with the elements of replacements. [...]
inherited
retainWhere(bool test(E element)) → void
Removes all objects from this list that fail to satisfy test. [...]
inherited
setAll(int index, Iterable<E> iterable) → void
Overwrites elements with the objects of iterable. [...]
inherited
setRange(int start, int end, Iterable<E> iterable, [int skipCount = 0]) → void
Writes some elements of iterable into a range of this list. [...]
inherited
shuffle([Random? random]) → void
Shuffles the elements of this list randomly.
inherited
singleWhere(bool test(E element), {E orElse()?}) → E
Returns the single element that satisfies test. [...]
inherited
skip(int count) Iterable<E>
Returns an Iterable that provides all but the first count elements. [...]
inherited
skipWhile(bool test(E element)) Iterable<E>
Returns an Iterable that skips leading elements while test is satisfied. [...]
inherited
sort([int compare(E a, E b)?]) → void
Sorts this list according to the order specified by the compare function. [...]
inherited
sublist(int start, [int? end]) List<E>
Returns a new list containing the elements between start and end. [...]
inherited
take(int count) Iterable<E>
Returns a lazy iterable of the count first elements of this iterable. [...]
inherited
takeWhile(bool test(E element)) Iterable<E>
Returns a lazy iterable of the leading elements satisfying test. [...]
inherited
toList({bool growable = true}) List<E>
Creates a List containing the elements of this Iterable. [...]
inherited
toSet() Set<E>
Creates a Set containing the same elements as this iterable. [...]
inherited
toString() String
A string representation of this object. [...]
inherited
where(bool test(E element)) Iterable<E>
Returns a new lazy Iterable with all elements that satisfy the predicate test. [...]
inherited
whereType<T>() Iterable<T>
Returns a new lazy Iterable with all elements that have type T. [...]
inherited

Operators

operator +(List<E> other) List<E>
Returns the concatenation of this list and other. [...]
inherited
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 list) String
Converts a List to a String. [...]