com.facebook.litho.widget

Class HorizontalScroll

java.lang.Object

com.facebook.litho.ComponentLifecycle

com.facebook.litho.Component

com.facebook.litho.widget.HorizontalScroll

All Implemented Interfaces:

Equivalence<Component>, EventDispatcher, EventTriggerTarget, HasEventDispatcher, HasEventTrigger, Cloneable

public final class HorizontalScroll
extends Component

A component that wraps another component and allow it to be horizontally scrollable. It's analogous to a HorizontalScrollView.

See Also:

com.facebook.litho.widget.HorizontalScrollSpec

Required Props

contentProps

Type:

com.facebook.litho.Component

Optional Props

eventsController

Type:

com.facebook.litho.widget.HorizontalScrollEventsController

fillViewport

Type:

boolean

initialScrollPosition

Type:

int

onScrollChangeListener

Type:

com.facebook.litho.widget.HorizontalScrollSpec.OnScrollChangeListener

scrollbarEnabled

Type:

boolean

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	HorizontalScroll.Builder

Nested classes/interfaces inherited from class com.facebook.litho.Component

Component.ContainerBuilder<T extends Component.ContainerBuilder<T>>

Nested classes/interfaces inherited from class com.facebook.litho.ComponentLifecycle

ComponentLifecycle.MountType, ComponentLifecycle.RenderData, ComponentLifecycle.TransitionContainer

Method Summary

Modifier and Type	Method and Description
protected boolean	canMeasure() Whether this ComponentLifecycle is able to measure itself according to specific size constraints.
protected boolean	canPreallocate()
protected void	copyInterStageImpl(Component component)
static HorizontalScroll.Builder	create(ComponentContext context)
static HorizontalScroll.Builder	create(ComponentContext context, int defStyleAttr, int defStyleRes)
protected void	createInitialState(ComponentContext c)
ComponentLifecycle.MountType	getMountType() This indicates the type of the Object that will be returned by ComponentLifecycle.mount(com.facebook.litho.ComponentContext, java.lang.Object).
protected StateContainer	getStateContainer()
protected boolean	hasState()
boolean	isEquivalentTo(Component other) Compares this component to a different one to check if they are the same
protected boolean	isMountSizeDependent()
HorizontalScroll	makeShallowCopy()
protected void	onBoundsDefined(ComponentContext context, ComponentLayout layout) Called after the layout calculation is finished and the given ComponentLayout has its bounds defined.
protected Object	onCreateMountContent(Context c) Create the object that will be mounted in the LithoView.
protected void	onLoadStyle(ComponentContext c)
protected void	onMeasure(ComponentContext context, ComponentLayout layout, int widthSpec, int heightSpec, Size size)
protected void	onMount(ComponentContext context, Object horizontalScrollLithoView) Deploy all UI elements representing the final bounds defined in the given ComponentLayout.
protected void	onUnmount(ComponentContext context, Object mountedView) Unload UI elements associated with this component.
protected int	poolSize()
protected void	transferState(StateContainer _prevStateContainer, StateContainer _nextStateContainer) Call this to transfer the State annotated values between two Component with the same global scope.

Methods inherited from class com.facebook.litho.Component

bindDynamicProp, canResolve, clearCachedLayout, getCommonProps, getDynamicProps, getEventDispatcher, getHandle, getId, getKey, getScopedContext, getSimpleName, getSimpleNameDelegate, hasBackgroundSet, hasClickHandlerSet, measure, measureMightNotCacheInternalNode, recordEventTrigger, registerWorkingRange, retrieveValue, setScopedContext, updateInternalChildState, willRender

Methods inherited from class com.facebook.litho.ComponentLifecycle

acceptTriggerEvent, applyPreviousRenderData, callsShouldUpdateOnMount, createMountContent, dispatchErrorEvent, dispatchErrorEvent, dispatchOnEnteredRange, dispatchOnEvent, dispatchOnExitedRange, getEventTrigger, getEventTrigger, getExtraAccessibilityNodeAt, getExtraAccessibilityNodesCount, getTreePropsForChildren, hasAttachDetachCallback, hasChildLithoViews, implementsAccessibility, implementsExtraAccessibilityNodes, isLayoutSpecWithSizeSpecCheck, isPureRender, needsPreviousRenderData, newEventHandler, newEventTrigger, onAttached, onBind, onCreateLayout, onCreateLayoutWithSizeSpec, onCreateMountContentPool, onCreateTransition, onDetached, onError, onMeasureBaseline, onPopulateAccessibilityNode, onPopulateExtraAccessibilityNode, onPrepare, onShouldCreateLayoutWithNewSizeSpec, onUnbind, populateTreeProps, recordRenderData, resolve, shouldAlwaysRemeasure, shouldUpdate, shouldUseGlobalPool

Methods inherited from class java.lang.Object

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

Method Detail

getStateContainer

protected StateContainer getStateContainer()

Overrides:

getStateContainer in class Component

isEquivalentTo

public boolean isEquivalentTo(Component other)

Description copied from class: Component

Compares this component to a different one to check if they are the same

This is used to be able to skip rendering a component again. We avoid using the Object.equals(Object) so we can optimize the code better over time since we don't have to adhere to the contract required for a equals method.

Specified by:

isEquivalentTo in interface Equivalence<Component>

Overrides:

isEquivalentTo in class Component

Parameters:

other - the component to compare to

Returns:

true if the components are of the same type and have the same props

copyInterStageImpl

protected void copyInterStageImpl(Component component)

Overrides:

copyInterStageImpl in class Component

makeShallowCopy

public HorizontalScroll makeShallowCopy()

Overrides:

makeShallowCopy in class Component

onLoadStyle

protected void onLoadStyle(ComponentContext c)

Overrides:

onLoadStyle in class ComponentLifecycle

onMeasure

protected void onMeasure(ComponentContext context,
                         ComponentLayout layout,
                         int widthSpec,
                         int heightSpec,
                         Size size)

Overrides:

onMeasure in class ComponentLifecycle

canMeasure

protected boolean canMeasure()

Description copied from class: ComponentLifecycle

Whether this ComponentLifecycle is able to measure itself according to specific size constraints.

Overrides:

canMeasure in class ComponentLifecycle

onBoundsDefined

protected void onBoundsDefined(ComponentContext context,
                               ComponentLayout layout)

Description copied from class: ComponentLifecycle

Called after the layout calculation is finished and the given ComponentLayout has its bounds defined. You can use ComponentLayout.getX(), ComponentLayout.getY(), ComponentLayout.getWidth(), and ComponentLayout.getHeight() to get the size and position of the component in the layout tree.

Overrides:

onBoundsDefined in class ComponentLifecycle

Parameters:

context - The Context used by this component.

layout - The ComponentLayout with defined position and size.

onCreateMountContent

protected Object onCreateMountContent(Context c)

Description copied from class: ComponentLifecycle

Create the object that will be mounted in the LithoView.

Overrides:

onCreateMountContent in class ComponentLifecycle

Parameters:

c - The Context to be used to create the content.

Returns:

an Object that can be mounted for this component.

onMount

protected void onMount(ComponentContext context,
                       Object horizontalScrollLithoView)

Description copied from class: ComponentLifecycle

Deploy all UI elements representing the final bounds defined in the given ComponentLayout. Return either a Drawable or a View or null to be mounted.

Overrides:

onMount in class ComponentLifecycle

Parameters:

context - The ComponentContext to mount the component into.

onUnmount

protected void onUnmount(ComponentContext context,
                         Object mountedView)

Description copied from class: ComponentLifecycle

Unload UI elements associated with this component.

Overrides:

onUnmount in class ComponentLifecycle

Parameters:

context - The Context for this mount operation.

mountedView - The Drawable or View mounted by this component.

createInitialState

protected void createInitialState(ComponentContext c)

Overrides:

createInitialState in class ComponentLifecycle

getMountType

public ComponentLifecycle.MountType getMountType()

Description copied from class: ComponentLifecycle

This indicates the type of the Object that will be returned by ComponentLifecycle.mount(com.facebook.litho.ComponentContext, java.lang.Object).

Overrides:

getMountType in class ComponentLifecycle

Returns:

one of ComponentLifecycle.MountType

poolSize

protected int poolSize()

Overrides:

poolSize in class ComponentLifecycle

canPreallocate

protected boolean canPreallocate()

Overrides:

canPreallocate in class ComponentLifecycle

Returns:

true if this component can be preallocated.

isMountSizeDependent

protected boolean isMountSizeDependent()

Overrides:

isMountSizeDependent in class ComponentLifecycle

Returns:

true if Mount uses @FromMeasure or @FromOnBoundsDefined parameters.

hasState

protected boolean hasState()

Overrides:

hasState in class ComponentLifecycle

Returns:

true if the Component is using state, false otherwise.

transferState

protected void transferState(StateContainer _prevStateContainer,
                             StateContainer _nextStateContainer)

Description copied from class: ComponentLifecycle

Call this to transfer the State annotated values between two Component with the same global scope.

Overrides:

transferState in class ComponentLifecycle

create

public static HorizontalScroll.Builder create(ComponentContext context)

create

public static HorizontalScroll.Builder create(ComponentContext context,
                                              int defStyleAttr,
                                              int defStyleRes)