com.facebook.litho.widget

Class Text

java.lang.Object

com.facebook.litho.ComponentLifecycle

com.facebook.litho.Component

com.facebook.litho.widget.Text

All Implemented Interfaces:

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

public final class Text
extends Component

Component to render text. See text-widget for more details.

Example Text usage:

 final SpannableStringBuilder spannable = new SpannableStringBuilder();
 spannable.setSpan(new StyleSpan(Typeface.BOLD), start, end, Spannable.SPAN_INCLUSIVE_INCLUSIVE);
 Text.create(c)
    .text(spannable) // String can be used
    .textSizeDip(20)
    .maxLines(3)
    .ellipsize(TextUtils.TruncateAt.END)
    .textColor(Color.BLACK)
    .build()
 

See Also:

com.facebook.litho.widget.TextSpec

Required Props

text

Text to display.

Type:

java.lang.CharSequence

Optional Props

accessibleClickableSpans

Whether the text can contain accessible clickable spans.

Type:

boolean

alignment

Type:

com.facebook.litho.widget.TextAlignment

breakStrategy

Break strategy to use for multi-line text.

Type:

int

clickableSpanExpandedOffset

Click offset amount to determine how far off the ClickableSpan bounds user can click to be able to trigger ClickableSpan's click action. This could be useful in a densely lined text with links like 'Continue reading ...' in NewsFeed to be able to click that easily.

Type:

float

clipToBounds

If the text should be clipped inside component bounds. Default: {@code true}

Type:

boolean

customEllipsisText

Text used to replace the standard Android ... ellipsis at the end of truncated lines. Warning: specifying this prop causes measurement to run twice. This can have a serious performance cost, especially on older devices!

Type:

java.lang.CharSequence

ellipsize

If set, specifies the position of the text to be ellipsized.

Type:

android.text.TextUtils.TruncateAt

extraSpacing

Extra spacing between the lines of text.

Type:

float

glyphWarming

If set, pre-renders the text to an off-screen Canvas to boost performance.

Type:

boolean

highlightColor

Color for an optional highlight of the text.

Type:

int

highlightEndOffset

End offset for an optional highlight of the text.

Type:

int

highlightStartOffset

Start offset for an optional highlight of the text.

Type:

int

hyphenationFrequency

How frequently to hyphenate text.

Type:

int

isSingleLine

If set, makes the text to be rendered in a single line.

Type:

boolean

justificationMode

How to justify the text. See {@link android.text.Layout}

Type:

int

letterSpacing

Text letter-spacing. Typical values for slight expansion will be around 0.05 ems. Negative values tighten text.

Type:

float

lineHeight

Controls the line height of text (the amount of vertical space reserved for each line of text).

Type:

float

linkColor

Color for links in the text.

Type:

int

maxEms

Makes the text to be max ems wide.

Type:

int

maxLines

Maximum number of lines to show.

Type:

int

maxTextWidth

Makes the text to be max pixels wide.

Type:

int

minEms

Makes the text to be mim ems wide.

Type:

int

minLines

Minimum number of lines to show.

Type:

int

minTextWidth

Makes the text to be min pixels wide.

Type:

int

minimallyWide

If set, multi-line text width is determined by the widest line, rather than the overall layout width. This can eliminate empty space in word-wrapped text with line breaks preceding lengthy words or spans.

Type:

boolean

minimallyWideThreshold

If set, {@code minimallyWide} logic will not run for text whose minimal width is smaller than its normal width by less than the threshold.

Type:

int

shadowColor

Color for the shadow underneath the text.

Type:

int

shadowDx

Horizontal offset of the shadow.

Type:

float

shadowDy

Vertical offset of the shadow.

Type:

float

shadowRadius

Blur radius of the shadow.

Type:

float

shouldIncludeFontPadding

If set, uses extra padding for ascenders and descenders.

Type:

boolean

spacingMultiplier

Extra spacing between the lines of text, as a multiplier.

Type:

float

spanListener

Listener to override click and/or longclick actions of spannables extracted from text. This can be used to avoid memory leaks if the click/long click actions require a context, since spannables are stored statically in memory.

Type:

com.facebook.litho.widget.ClickableSpanListener

textAlignment

Alignment of the text within its container.

Type:

android.text.Layout.Alignment

textColor

Color of the text.

Type:

int

textColorStateList

ColorStateList of the text.

Type:

android.content.res.ColorStateList

textDirection

Heuristic to use to determine the direction of the text.

Type:

androidx.core.text.TextDirectionHeuristicCompat

textOffsetOnTouchHandler

A handler for touch events that need to know their character offset into the text. Will only fire on ACTION_DOWN events that occur at an index within the text.

Type:

com.facebook.litho.EventHandler

textSize

Size of the text.

Type:

int

textStyle

Style (bold, italic, bolditalic) for the text.

Type:

int

typeface

Typeface for the text.

Type:

android.graphics.Typeface

verticalGravity

Vertical gravity for the text within its container.

Type:

com.facebook.litho.widget.VerticalGravity

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Text.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 Text.Builder	create(ComponentContext context)
static Text.Builder	create(ComponentContext context, int defStyleAttr, int defStyleRes)
protected int	getExtraAccessibilityNodeAt(int x, int y) Get extra accessibility node id at a given point within the component.
protected int	getExtraAccessibilityNodesCount() The number of extra accessibility nodes that this component wishes to provides to the accessibility system.
ComponentLifecycle.MountType	getMountType() This indicates the type of the Object that will be returned by ComponentLifecycle.mount(com.facebook.litho.ComponentContext, java.lang.Object).
static EventHandler	getTextOffsetOnTouchEventHandler(ComponentContext context)
boolean	implementsAccessibility() Whether this component will populate any accessibility nodes or events that are passed to it.
boolean	implementsExtraAccessibilityNodes() Whether this component will expose any virtual views to the accessibility framework
boolean	isEquivalentTo(Component other) Compares this component to a different one to check if they are the same
protected boolean	isMountSizeDependent()
boolean	isPureRender()
Text	makeShallowCopy()
protected void	onBoundsDefined(ComponentContext c, 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 c, Object textDrawable) Deploy all UI elements representing the final bounds defined in the given ComponentLayout.
protected void	onPopulateAccessibilityNode(View host, AccessibilityNodeInfoCompat node) Populate an accessibility node with information about the component.
protected void	onPopulateExtraAccessibilityNode(AccessibilityNodeInfoCompat node, int extraNodeIndex, int componentBoundsLeft, int componentBoundsTop) Populate an extra accessibility node.
protected void	onUnmount(ComponentContext c, Object textDrawable) Unload UI elements associated with this component.
protected int	poolSize()

Methods inherited from class com.facebook.litho.Component

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

Methods inherited from class com.facebook.litho.ComponentLifecycle

acceptTriggerEvent, applyPreviousRenderData, callsShouldUpdateOnMount, createInitialState, createMountContent, dispatchErrorEvent, dispatchErrorEvent, dispatchOnEnteredRange, dispatchOnEvent, dispatchOnExitedRange, getEventTrigger, getEventTrigger, getTreePropsForChildren, hasAttachDetachCallback, hasChildLithoViews, hasState, isLayoutSpecWithSizeSpecCheck, needsPreviousRenderData, newEventHandler, newEventTrigger, onAttached, onBind, onCreateLayout, onCreateLayoutWithSizeSpec, onCreateMountContentPool, onCreateTransition, onDetached, onError, onMeasureBaseline, onPrepare, onShouldCreateLayoutWithNewSizeSpec, onUnbind, populateTreeProps, recordRenderData, resolve, shouldAlwaysRemeasure, shouldUpdate, shouldUseGlobalPool, transferState

Methods inherited from class java.lang.Object

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

Method Detail

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 Text 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 c,
                               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:

c - 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 c,
                       Object textDrawable)

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:

c - The ComponentContext to mount the component into.

onUnmount

protected void onUnmount(ComponentContext c,
                         Object textDrawable)

Description copied from class: ComponentLifecycle

Unload UI elements associated with this component.

Overrides:

onUnmount in class ComponentLifecycle

Parameters:

c - The Context for this mount operation.

textDrawable - The Drawable or View mounted by this component.

onPopulateAccessibilityNode

protected void onPopulateAccessibilityNode(View host,
                                           AccessibilityNodeInfoCompat node)

Description copied from class: ComponentLifecycle

Populate an accessibility node with information about the component.

Overrides:

onPopulateAccessibilityNode in class ComponentLifecycle

node - node to populate

implementsAccessibility

public boolean implementsAccessibility()

Description copied from class: ComponentLifecycle

Whether this component will populate any accessibility nodes or events that are passed to it.

Overrides:

implementsAccessibility in class ComponentLifecycle

Returns:

true if the component implements accessibility info

getExtraAccessibilityNodesCount

protected int getExtraAccessibilityNodesCount()

Description copied from class: ComponentLifecycle

The number of extra accessibility nodes that this component wishes to provides to the accessibility system.

Overrides:

getExtraAccessibilityNodesCount in class ComponentLifecycle

Returns:

the number of extra nodes

onPopulateExtraAccessibilityNode

protected void onPopulateExtraAccessibilityNode(AccessibilityNodeInfoCompat node,
                                                int extraNodeIndex,
                                                int componentBoundsLeft,
                                                int componentBoundsTop)

Description copied from class: ComponentLifecycle

Populate an extra accessibility node.

Overrides:

onPopulateExtraAccessibilityNode in class ComponentLifecycle

Parameters:

node - node to populate

extraNodeIndex - index of extra node

componentBoundsLeft - left bound of the mounted component

componentBoundsTop - top bound of the mounted component

implementsExtraAccessibilityNodes

public boolean implementsExtraAccessibilityNodes()

Description copied from class: ComponentLifecycle

Whether this component will expose any virtual views to the accessibility framework

Overrides:

implementsExtraAccessibilityNodes in class ComponentLifecycle

Returns:

true if the component exposes extra accessibility nodes

getExtraAccessibilityNodeAt

protected int getExtraAccessibilityNodeAt(int x,
                                          int y)

Description copied from class: ComponentLifecycle

Get extra accessibility node id at a given point within the component.

Overrides:

getExtraAccessibilityNodeAt in class ComponentLifecycle

Parameters:

x - x co-ordinate within the mounted component

y - y co-ordinate within the mounted component

Returns:

the extra virtual view id if one is found, otherwise ExploreByTouchHelper#INVALID_ID

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.

isPureRender

public boolean isPureRender()

Overrides:

isPureRender in class ComponentLifecycle

getTextOffsetOnTouchEventHandler

public static EventHandler getTextOffsetOnTouchEventHandler(ComponentContext context)

create

public static Text.Builder create(ComponentContext context)

create

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