com.facebook.litho.widget

Class ComponentWarmer

java.lang.Object

com.facebook.litho.widget.ComponentWarmer

public class ComponentWarmer
extends Object

Pool for pre-computing and storing ComponentTrees. Can be used to pre-compute and store ComponentTrees before they are inserted in a RecyclerBinder. The RecyclerBinder will fetch the precomputed ComponentTree from the pool if it's available instead of computing a layout calculation when the item needs to be computed.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ComponentWarmer.Cache
static interface	ComponentWarmer.CacheListener
static interface	ComponentWarmer.ComponentTreeHolderPreparer
class	ComponentWarmer.ComponentTreeHolderPreparerWithSizeImpl
static interface	ComponentWarmer.ComponentWarmerReadyListener

Field Summary

Fields

Modifier and Type	Field and Description
static String	COMPONENT_WARMER_PREPARE_HANDLER
static String	COMPONENT_WARMER_TAG
static int	DEFAULT_MAX_SIZE

Constructor Summary

Constructors

Constructor and Description
ComponentWarmer() Creates a ComponentWarmer instance which is not ready to prepare items yet.
ComponentWarmer(ComponentContext c, int widthSpec, int heightSpec) Sets up a ComponentWarmer.ComponentTreeHolderPreparerWithSizeImpl as the ComponentWarmer.ComponentTreeHolderPreparer of this instance.
ComponentWarmer(ComponentWarmer.Cache cache)
ComponentWarmer(ComponentWarmer.ComponentTreeHolderPreparer factory) Creates a ComponentWarmer which will use the provided ComponentTreeHolderPreparer instance to create ComponentTreeHolder instances for preparing and caching items.
ComponentWarmer(ComponentWarmer.ComponentTreeHolderPreparer factory, ComponentWarmer.Cache cache) Same as ComponentWarmer(ComponentTreeHolderPreparer) but uses the passed in Cache instance to manage the internal cache.
ComponentWarmer(RecyclerBinder recyclerBinder) Creates a ComponentWarmer for this RecyclerBinder.
ComponentWarmer(RecyclerBinder recyclerBinder, ComponentWarmer.Cache cache) Same as ComponentWarmer(RecyclerBinder) but uses the passed in Cache instance to manage the internal cache.

Method Summary

Modifier and Type	Method and Description
void	cancelPrepare(String tag) Cancels the prepare execution for the item with the given tag if it's currently running and it removes the item from the cache.
ComponentTreeHolder	consume(String tag) If it exists, it returns the cached ComponentTreeHolder for this tag and removes it from cache.
void	evictAll()
boolean	isReady()
void	prepare(String tag, ComponentRenderInfo componentRenderInfo, Size size) Synchronously prepare the ComponentTree for the given ComponentRenderInfo.
void	prepare(String tag, ComponentRenderInfo componentRenderInfo, Size size, LithoHandler handler) Synchronously post preparing the ComponentTree for the given ComponentRenderInfo to the handler.
void	prepareAsync(String tag, ComponentRenderInfo componentRenderInfo) Asynchronously prepare the ComponentTree for the given ComponentRenderInfo.
void	remove(String tag)
void	setComponentWarmerReadyListener(ComponentWarmer.ComponentWarmerReadyListener listener)
void	setReleaseEvictedEntries(boolean releaseEvictedEntries)
void	setSkipAlreadyPreparedKeys(boolean skipAlreadyPreparedKeys)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

COMPONENT_WARMER_TAG

public static final String COMPONENT_WARMER_TAG

See Also:

Constant Field Values

COMPONENT_WARMER_PREPARE_HANDLER

public static final String COMPONENT_WARMER_PREPARE_HANDLER

See Also:

Constant Field Values

DEFAULT_MAX_SIZE

public static final int DEFAULT_MAX_SIZE

See Also:

Constant Field Values

Constructor Detail

ComponentWarmer

public ComponentWarmer(ComponentContext c,
                       int widthSpec,
                       int heightSpec)

Sets up a ComponentWarmer.ComponentTreeHolderPreparerWithSizeImpl as the ComponentWarmer.ComponentTreeHolderPreparer of this instance. All prepare calls will use the provided width and height specs for preparing, until this instance is configured on a RecyclerBinder and a new ComponentWarmer.ComponentTreeHolderPreparer created by the RecyclerBinder is used, which uses the RecyclerBinder's measurements.

ComponentWarmer

public ComponentWarmer()

Creates a ComponentWarmer instance which is not ready to prepare items yet. If trying to prepare an item before the ComponentWarmer is ready, the requests will be enqueued and will only be executed once this instance is bound to a ComponentTreeHolderPreparer.

Pass in a ComponentWarmer.ComponentWarmerReadyListener instance to be notified when the instance is ready. Uses a LruCache to manage the internal cache.

ComponentWarmer

public ComponentWarmer(ComponentWarmer.Cache cache)

ComponentWarmer

public ComponentWarmer(RecyclerBinder recyclerBinder)

Creates a ComponentWarmer for this RecyclerBinder. This ComponentWarmer instance will use the same ComponentTree factory as the RecyclerBinder. The RecyclerBinder will query the ComponentWarmer for cached items before creating new ComponentTrees. Uses a LruCache to manage the internal cache.

ComponentWarmer

public ComponentWarmer(RecyclerBinder recyclerBinder,
                       ComponentWarmer.Cache cache)

Same as ComponentWarmer(RecyclerBinder) but uses the passed in Cache instance to manage the internal cache.

ComponentWarmer

public ComponentWarmer(ComponentWarmer.ComponentTreeHolderPreparer factory)

Creates a ComponentWarmer which will use the provided ComponentTreeHolderPreparer instance to create ComponentTreeHolder instances for preparing and caching items. Uses a LruCache to manage the internal cache.

ComponentWarmer

public ComponentWarmer(ComponentWarmer.ComponentTreeHolderPreparer factory,
                       ComponentWarmer.Cache cache)

Same as ComponentWarmer(ComponentTreeHolderPreparer) but uses the passed in Cache instance to manage the internal cache.

Method Detail

setComponentWarmerReadyListener

public void setComponentWarmerReadyListener(ComponentWarmer.ComponentWarmerReadyListener listener)

setSkipAlreadyPreparedKeys

public void setSkipAlreadyPreparedKeys(boolean skipAlreadyPreparedKeys)

setReleaseEvictedEntries

public void setReleaseEvictedEntries(boolean releaseEvictedEntries)

isReady

public boolean isReady()

prepare

public void prepare(String tag,
                    ComponentRenderInfo componentRenderInfo,
                    Size size,
                    LithoHandler handler)

Synchronously post preparing the ComponentTree for the given ComponentRenderInfo to the handler.

prepare

public void prepare(String tag,
                    ComponentRenderInfo componentRenderInfo,
                    Size size)

Synchronously prepare the ComponentTree for the given ComponentRenderInfo.

Parameters:

tag - Set a tag on the prepared ComponentTree so it can be retrieved from cache.

componentRenderInfo - to be prepared.

size - if not null, it will have the size result at the end of computing the layout. Prepare calls which require a size result to be computed cannot be cancelled (@see cancelPrepare(String)). Prepare calls which are not immediately executed because the ComponentWarmer is not ready will not set a size.

prepareAsync

public void prepareAsync(String tag,
                         ComponentRenderInfo componentRenderInfo)

Asynchronously prepare the ComponentTree for the given ComponentRenderInfo.

The thread on which this ComponentRenderInfo is prepared is the background thread that the associated RecyclerBinder uses. To change it, you can implement a ComponentWarmer.ComponentTreeHolderPreparer and configure the layout handler when creating the ComponentTree.

Alternatively you can use prepare(String, ComponentRenderInfo, Size, LithoHandler) to synchronously post the prepare call to a custom handler.

evictAll

public void evictAll()

remove

public void remove(String tag)

consume

public ComponentTreeHolder consume(String tag)

If it exists, it returns the cached ComponentTreeHolder for this tag and removes it from cache.

cancelPrepare

public void cancelPrepare(String tag)

Cancels the prepare execution for the item with the given tag if it's currently running and it removes the item from the cache.