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ParallaxTarget

public abstract class ParallaxTarget
extends Object

java.lang.Object
   ↳ androidx.leanback.widget.ParallaxTarget

ParallaxTarget is responsible for updating the target through the update(float) method or the directUpdate(Number) method when isDirectMapping() is true. When isDirectMapping() is false, ParallaxEffect transforms the values of Parallax, which represents the current state of UI, into a float value between 0 and 1. That float value is passed into update(float) method.

Summary

Nested classes

class ParallaxTarget.DirectPropertyTarget<T, V extends Number>

DirectPropertyTarget is to support direct mapping into either Integer Property or Float Property. 

class ParallaxTarget.PropertyValuesHolderTarget

PropertyValuesHolderTarget is an implementation of ParallaxTarget that uses PropertyValuesHolder to update the target object. 

Public constructors

ParallaxTarget()

Public methods

void directUpdate(Number value)

Directly update the target using a float or int value.

boolean isDirectMapping()

Returns true if the ParallaxTarget is directly mapping from source value, directUpdate(Number) will be used to update value, otherwise update(fraction) will be called to update value.

void update(float fraction)

Implementation class is supposed to update target with the provided fraction (between 0 and 1).

Inherited methods

Public constructors

ParallaxTarget

public ParallaxTarget ()

Public methods

directUpdate

public void directUpdate (Number value)

Directly update the target using a float or int value. Called when isDirectMapping() is true.

Parameters
value Number: Either int or float value.

See also:

isDirectMapping

public boolean isDirectMapping ()

Returns true if the ParallaxTarget is directly mapping from source value, directUpdate(Number) will be used to update value, otherwise update(fraction) will be called to update value. Default implementation returns false.

Returns
boolean True if direct mapping, false otherwise.

update

public void update (float fraction)

Implementation class is supposed to update target with the provided fraction (between 0 and 1). The fraction represents percentage of completed change (e.g. scroll) on target. Called only when isDirectMapping() is false.

Parameters
fraction float: Fraction between 0 to 1.

See also: