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IterableChanges

interface

An object describing the changes in the Iterable collection since last time IterableDiffer#diff() was invoked.

interface IterableChanges<V> {
  forEachItem(fn: (record: IterableChangeRecord<V>) => void): void
  forEachOperation(fn: (record: IterableChangeRecord<V>, previousIndex: number, currentIndex: number) => void): void
  forEachPreviousItem(fn: (record: IterableChangeRecord<V>) => void): void
  forEachAddedItem(fn: (record: IterableChangeRecord<V>) => void): void
  forEachMovedItem(fn: (record: IterableChangeRecord<V>) => void): void
  forEachRemovedItem(fn: (record: IterableChangeRecord<V>) => void): void
  forEachIdentityChange(fn: (record: IterableChangeRecord<V>) => void): void
}

Class implementations

Methods

forEachItem()

Iterate over all changes. IterableChangeRecord will contain information about changes to each item.

forEachItem(fn: (record: IterableChangeRecord<V>) => void): void

Parameters
fn (record: IterableChangeRecord ) => void
Returns

void
forEachOperation()

Iterate over a set of operations which when applied to the original Iterable will produce the new Iterable.

forEachOperation(fn: (record: IterableChangeRecord<V>, previousIndex: number, currentIndex: number) => void): void

Parameters
fn (record: IterableChangeRecord , previousIndex: number, currentIndex: number) => void
Returns

void

NOTE: These are not necessarily the actual operations which were applied to the original Iterable, rather these are a set of computed operations which may not be the same as the ones applied.
forEachPreviousItem()

Iterate over changes in the order of original Iterable showing where the original items have moved.

forEachPreviousItem(fn: (record: IterableChangeRecord<V>) => void): void

Parameters
fn (record: IterableChangeRecord ) => void
Returns

void
forEachAddedItem()

Iterate over all added items.

forEachAddedItem(fn: (record: IterableChangeRecord<V>) => void): void

Parameters
fn (record: IterableChangeRecord ) => void
Returns

void
forEachMovedItem()

Iterate over all moved items.

forEachMovedItem(fn: (record: IterableChangeRecord<V>) => void): void

Parameters
fn (record: IterableChangeRecord ) => void
Returns

void
forEachRemovedItem()

Iterate over all removed items.

forEachRemovedItem(fn: (record: IterableChangeRecord<V>) => void): void

Parameters
fn (record: IterableChangeRecord ) => void
Returns

void
forEachIdentityChange()

Iterate over all items which had their identity (as computed by the TrackByFunction) changed.

forEachIdentityChange(fn: (record: IterableChangeRecord<V>) => void): void

Parameters
fn (record: IterableChangeRecord ) => void
Returns

void

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Licensed under the Creative Commons Attribution License 4.0.
https://v12.angular.io/api/core/IterableChanges