litho-core/com.facebook.litho/ComponentTree

ComponentTree

open class ComponentTree : LithoVisibilityEventsListener, StateUpdater, MountedViewReference, ErrorComponentReceiver, LithoTreeLifecycleProvider

Represents a tree of components and controls their life cycle. ComponentTree takes in a single root component and recursively invokes its OnCreateLayout to create a tree of components. ComponentTree is responsible for refreshing the mounted state of a component with new props.

The usual use case for ComponentTree is: ComponentTree component = ComponentTree.create(context, MyComponent.create()); myHostView.setRoot(component);

Types

Builder

class Builder

A builder class that can be used to create a ComponentTree.

MeasureListener

interface MeasureListener

NewLayoutStateReadyListener

interface NewLayoutStateReadyListener

Listener that will be notified when a new LayoutState is computed and ready to be committed to this ComponentTree.

Properties

INVALID_ID

val INVALID_ID: Int = -1

INVALID_LAYOUT_VERSION

val INVALID_LAYOUT_VERSION: Int = -1

SIZE_UNINITIALIZED

val SIZE_UNINITIALIZED: Int = -1

STATE_UPDATES_IN_LOOP_THRESHOLD

val STATE_UPDATES_IN_LOOP_THRESHOLD: Int = 50

Functions

acquireTreeState

open fun acquireTreeState(): TreeState

Provides a new instance of the TreeState that is initialized with the TreeState held by the ComponentTree.

addMeasureListener

open fun addMeasureListener(@Nullable measureListener: ComponentTree.MeasureListener)

The provided measureListener will be called when a valid layout is commited.

addOnReleaseListener

open fun addOnReleaseListener(listener: LithoTreeLifecycleProvider.OnReleaseListener)

applyLazyStateUpdatesForContainer

open fun applyLazyStateUpdatesForContainer(componentKey: String, container: StateContainer, isLayoutState: Boolean): StateContainer

cancelLayoutAndReleaseTree

open fun cancelLayoutAndReleaseTree()

canSkipStateUpdate

open fun <T> canSkipStateUpdate(globalKey: String, hookStateIndex: Int, @Nullable newValue: T, isLayoutState: Boolean): Boolean

open fun <T> canSkipStateUpdate(newValueFunction: (in T) -> out T, globalKey: String, hookStateIndex: Int, isLayoutState: Boolean): Boolean

checkWorkingRangeAndDispatch

open fun checkWorkingRangeAndDispatch(position: Int, firstVisibleIndex: Int, lastVisibleIndex: Int, firstFullyVisibleIndex: Int, lastFullyVisibleIndex: Int)

Check if the any child components stored in LayoutState have entered/exited the working range, and dispatch the event to trigger the corresponding registered methods.

clearMeasureListener

open fun clearMeasureListener(measureListener: ComponentTree.MeasureListener)

create

open fun create(context: ComponentContext): ComponentTree.Builder

open fun create(context: ComponentContext, @Nullable root: Component): ComponentTree.Builder

open fun create(context: ComponentContext, root: Component.Builder<out Any>): ComponentTree.Builder

open fun create(context: ComponentContext, @Nullable root: Component, @Nullable controller: LithoVisibilityEventsController): ComponentTree.Builder

createNestedComponentTree

open fun createNestedComponentTree(parentContext: ComponentContext): ComponentTree.Builder

open fun createNestedComponentTree(parentContext: ComponentContext, @Nullable component: Component): ComponentTree.Builder

Creates a ComponentTree nested inside the ComponentTree of the provided parentContext.