CombinedMapView<K, V> class

Returns a new map that represents maps flattened into a single map.

All methods and accessors treat the new map as-if it were a single concatenated map, but the underlying implementation is based on lazily accessing individual map instances. In the occasion where a key occurs in multiple maps the first value is returned.

The resulting map has an index operator ([]) that is O(maps), rather than O(1), and the map is unmodifiable, but underlying changes to these maps are still accessible from the resulting map.

The length getter is O(M) where M is the total number of entries in all maps, since it has to remove duplicate entries.

Inheritance

• Object
• MapBase<K, V>
• UnmodifiableMapBase<K, V>
• CombinedMapView

Available extensions

• DeepGetOnMapExt
• GenericTypeOnMapExt
• MapKeysAndValyesOnMapExt
• MapWithDefaultOnMapExt
• MaybeAddToMapExt
• NonNullKeysOnMapExt
• NonNullsOnMapExt
• NonNullValuesOnMapExt
• NullIfEmptyOnMapExt
• SetNestedValueOnMapExt
• TraverseMapOnMapExt
• UnmodifiableOnMapExt

Constructors

CombinedMapView(Iterable<Map<K, V>> _maps)

Create a new combined view of multiple maps.

Properties

entries → Iterable<MapEntry<K, V>>

The map entries of this Map.

no setter, inherited

genericTypeKey → Type

Available on Map<K, V>, provided by the GenericTypeOnMapExt extension

Returns the generic type of the map's keys.

no setter

genericTypeValue → Type

Available on Map<K, V>, provided by the GenericTypeOnMapExt extension

Returns the generic type of the map's values.

no setter

hashCode → int

The hash code for this object.

no setter, inherited

isEmpty → bool

Whether there is no key/value pair in the map.

no setter, inherited

isNotEmpty → bool

Whether there is at least one key/value pair in the map.

no setter, inherited

keys → Iterable<K>

The keys of this.

no setter, override

length → int

The number of key/value pairs in the map.

no setter, inherited

nonNullKeys → Map<K, V>

Available on Map<K?, V>, provided by the NonNullKeysOnMapExt extension

Returns a new map with all non-null keys and values.

no setter

nonNulls → Map<K, V>

Available on Map<K?, V?>, provided by the NonNullsOnMapExt extension

Returns a new map with all non-null keys and values.

no setter

nonNullValues → Map<K, V>

Available on Map<K, V?>, provided by the NonNullValuesOnMapExt extension

Returns a new map with all non-null keys and values.

no setter

nullIfEmpty → Map<T1, T2>?

Available on Map<T1, T2>, provided by the NullIfEmptyOnMapExt extension

Returns null if the Map is empty, otherwise returns the Map.

no setter

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

unmodifiable → Map<K, V>

Available on Map<K, V>, provided by the UnmodifiableOnMapExt extension

no setter

values → Iterable<V>

The values of this Map.

no setter, inherited

Methods

addAll(Map<K, V> other) → void

This operation is not supported by an unmodifiable map.

inherited

addEntries(Iterable<MapEntry<K, V>> entries) → void

This operation is not supported by an unmodifiable map.

inherited

cast<RK, RV>() → Map<RK, RV>

Provides a view of this map as having RK keys and RV instances, if necessary.

inherited

clear() → void

This operation is not supported by an unmodifiable map.

inherited

containsKey(Object? key) → bool

Whether this map contains the given key.

inherited

containsValue(Object? value) → bool

Whether this map contains the given value.

inherited

deepGet(String path, {String separator = '.'}) → dynamic

Available on Map, provided by the DeepGetOnMapExt extension

Safely retrieves and converts a value from a nested data structure using a dot-separated path.

deepGetFromSegments(Iterable pathSegments) → dynamic

Available on Map, provided by the DeepGetOnMapExt extension

Safely retrieves and converts a value from a nested data structure using a list of path pathSegments.

filterByExcludedKeys(List<K> excludedKeys) → Map<K, V>

Available on Map<K, V>, provided by the MapWithDefaultOnMapExt extension

Filters the map's entries based on a list of excluded keys. Returns a new map excluding the key-value pairs where the key is found within the excludedKeys.

filterByExcludedValues(List<V> excludedValues) → Map<K, V>

Available on Map<K, V>, provided by the MapWithDefaultOnMapExt extension

Filters the map's entries based on a list of excluded values. Returns a new map excluding the key-value pairs where the value is found within the excludedValues.

filterByIncludedKeys(List<K> includedKeys) → Map<K, V>

Available on Map<K, V>, provided by the MapWithDefaultOnMapExt extension

Filters the map's entries based on a list of included keys. Returns a new map containing only the key-value pairs where the key is found within the includedKeys.

filterByIncludedValues(List<V> includedValues) → Map<K, V>

Available on Map<K, V>, provided by the MapWithDefaultOnMapExt extension

Filters the map's entries based on a list of included values. Returns a new map containing only the key-value pairs where the value is found within the includedValues.

forEach(void action(K key, V value)) → void

Applies action to each key/value pair of the map.

inherited

map<K2, V2>(MapEntry<K2, V2> transform(K key, V value)) → Map<K2, V2>

Returns a new map where all entries of this map are transformed by the given convert function.

inherited

mapKeys<K2>(K2 mapper(K1 key)) → Map<K2, V1>

Available on Map<K1, V1>, provided by the MapKeysAndValyesOnMapExt extension

Returns a new map with new keys and the same values.

mapValues<V2>(V2 mapper(V1 value)) → Map<K1, V2>

Available on Map<K1, V1>, provided by the MapKeysAndValyesOnMapExt extension

Returns a new map with the same keys and new values.

mapWithDefault(dynamic defaultValue) → Map<K, dynamic>

Available on Map<K, V>, provided by the MapWithDefaultOnMapExt extension

Returns a new map with the same keys as this map but with the specified defaultValue for all values that are null. If defaultValue is null, it simply returns a copy of the original map.

maybeAdd(Map<T1, T2>? add) → Map<T1, T2>

Available on Map<T1, T2>, provided by the MaybeAddToMapExt extension

Adds add to this its not null.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

putIfAbsent(K key, V ifAbsent()) → V

This operation is not supported by an unmodifiable map.

inherited

remove(Object? key) → V?

This operation is not supported by an unmodifiable map.

inherited

removeWhere(bool test(K key, V value)) → void

This operation is not supported by an unmodifiable map.

inherited

setNestedValue(List keyPath, dynamic value) → void

Available on Map, provided by the SetNestedValueOnMapExt extension

Sets a value in a nested map structure, creating intermediate maps as needed.

toString() → String

A string representation of this object.

inherited

traverse(List keys, {dynamic newValue}) → dynamic

Available on Map<K, V>, provided by the TraverseMapOnMapExt extension

See traverseMap.

update(K key, V update(V value), {V ifAbsent()?}) → V

This operation is not supported by an unmodifiable map.

inherited

updateAll(V update(K key, V value)) → void

This operation is not supported by an unmodifiable map.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited

operator [](Object? key) → V?

The value for the given key, or null if key is not in the map.

override

operator []=(K key, V value) → void

This operation is not supported by an unmodifiable map.

inherited