public class Fade extends Visibility

java.lang.Object
   ↳ androidx.transition.Transition
     ↳ androidx.transition.Visibility
       ↳ androidx.transition.Fade

This transition tracks changes to the visibility of target views in the start and end scenes and fades views in or out when they become visible or non-visible. Visibility is determined by both the setVisibility state of the view as well as whether it is parented in the current view hierarchy.

The ability of this transition to fade out a particular view, and the way that that fading operation takes place, is based on the situation of the view in the view hierarchy. For example, if a view was simply removed from its parent, then the view will be added into a while fading. If a visible view is changed to be GONE or INVISIBLE, then the visibility will be changed to VISIBLE for the duration of the animation. However, if a view is in a hierarchy which is also altering its visibility, the situation can be more complicated. In general, if a view that is no longer in the hierarchy in the end scene still has a parent (so its parent hierarchy was removed, but it was not removed from its parent), then it will be left alone to avoid side-effects from improperly removing it from its parent. The only exception to this is if the previous Scene was created from a layout resource file, then it is considered safe to un-parent the starting scene view in order to fade it out.

A Fade transition can be described in a resource file by using the tag fade, along with the standard attributes of Fade and Transition.

Summary

Constants
static final int
IN = 1

Fading mode used in Fade to make the transition operate on targets that are appearing.
static final int
OUT = 2

Fading mode used in Fade to make the transition operate on targets that are disappearing.

Public constructors

Constructs a Fade transition that will fade targets in and out.
Fade(int fadingMode)

Constructs a Fade transition that will fade targets in and/or out, according to the value of fadingMode.
Fade(@NonNull Context context, @NonNull AttributeSet attrs)

Public methods
void

Captures the values in the start scene for the properties that this transition monitors.
boolean

Returns true if the Transition can be used by controlDelayedTransition.
@Nullable Animator
onAppear(
    @NonNull ViewGroup sceneRoot,
    @NonNull View view,
    @Nullable TransitionValues startValues,
    @Nullable TransitionValues endValues
)

The default implementation of this method returns a null Animator.
@Nullable Animator
onDisappear(
    @NonNull ViewGroup sceneRoot,
    @NonNull View view,
    @Nullable TransitionValues startValues,
    @Nullable TransitionValues endValues
)

The default implementation of this method returns a null Animator.

Inherited Constants
From androidx.transition.Transition
static final int

With setMatchOrder, chooses to match by getId.
static final int

With setMatchOrder, chooses to match by View instance.
static final int

With setMatchOrder, chooses to match by the android.widget.Adapter item id.
static final int

With setMatchOrder, chooses to match by getTransitionName.
From androidx.transition.Visibility
static final int

Mode used in setMode to make the transition operate on targets that are appearing.
static final int

Mode used in setMode to make the transition operate on targets that are disappearing.

Inherited methods
From androidx.transition.Transition
@NonNull Transition

Adds a listener to the set of listeners that are sent events through the life of an animation, such as start, repeat, and end.
@NonNull Transition
addTarget(@IdRes int targetId)

Adds the id of a target view that this Transition is interested in animating.
@NonNull Transition
addTarget(@NonNull String targetName)

Adds the transitionName of a target view that this Transition is interested in animating.
@NonNull Transition
addTarget(@NonNull Class<Object> targetType)

Adds the Class of a target view that this Transition is interested in animating.
@NonNull Transition

Sets the target view instances that this Transition is interested in animating.
@NonNull Transition
@NonNull Transition
excludeChildren(@IdRes int targetId, boolean exclude)

Whether to add the children of the given id to the list of targets to exclude from this transition.
@NonNull Transition
excludeChildren(@NonNull View target, boolean exclude)

Whether to add the children of given target to the list of target children to exclude from this transition.
@NonNull Transition
excludeChildren(@NonNull Class<Object> type, boolean exclude)

Whether to add the given type to the list of types whose children should be excluded from this transition.
@NonNull Transition
excludeTarget(@IdRes int targetId, boolean exclude)

Whether to add the given id to the list of target ids to exclude from this transition.
@NonNull Transition
excludeTarget(@NonNull String targetName, boolean exclude)

Whether to add the given transitionName to the list of target transitionNames to exclude from this transition.
@NonNull Transition
excludeTarget(@NonNull View target, boolean exclude)

Whether to add the given target to the list of targets to exclude from this transition.
@NonNull Transition
excludeTarget(@NonNull Class<Object> type, boolean exclude)

Whether to add the given type to the list of types to exclude from this transition.
long

Returns the duration set on this transition.
@Nullable Rect

Returns the epicenter as specified by the android.transition.Transition.EpicenterCallback or null if no callback exists.
@Nullable Transition.EpicenterCallback

Returns the callback used to find the epicenter of the Transition.
@Nullable TimeInterpolator

Returns the interpolator set on this transition.
@NonNull String

Returns the name of this Transition.
@NonNull PathMotion

Returns the algorithm object used to interpolate along two dimensions.
@Nullable TransitionPropagation

Returns the android.transition.TransitionPropagation used to calculate Animator start delays.
final @NonNull Transition

If this Transition is not part of a TransitionSet, this is returned.
long

Returns the startDelay set on this transition.
@NonNull List<Integer>

Returns the array of target IDs that this transition limits itself to tracking and animating.
@Nullable List<String>

Returns the list of target transitionNames that this transition limits itself to tracking and animating.
@Nullable List<Class<Object>>

Returns the list of target transitionNames that this transition limits itself to tracking and animating.
@NonNull List<View>

Returns the array of target views that this transition limits itself to tracking and animating.
@Nullable TransitionValues
getTransitionValues(@NonNull View view, boolean start)

This method can be called by transitions to get the TransitionValues for any particular view during the transition-playing process.
@NonNull Transition

Removes a listener from the set listening to this animation.
@NonNull Transition

Removes the given target from the list of targets that this Transition is interested in animating.
@NonNull Transition
removeTarget(@IdRes int targetId)

Removes the given targetId from the list of ids that this Transition is interested in animating.
@NonNull Transition

Removes the given targetName from the list of transitionNames that this Transition is interested in animating.
@NonNull Transition

Removes the given target from the list of targets that this Transition is interested in animating.
@NonNull Transition
setDuration(long duration)

Sets the duration of this transition.
void

Sets the callback to use to find the epicenter of a Transition.
@NonNull Transition

Sets the interpolator of this transition.
void
setMatchOrder(@Nullable int[] matches)

Sets the order in which Transition matches View start and end values.
void

Sets the algorithm used to calculate two-dimensional interpolation.
void

Sets the method for determining Animator start delays.
@NonNull Transition
setStartDelay(long startDelay)

Sets the startDelay of this transition.
@NonNull String
From androidx.transition.Visibility
void

Captures the values in the end scene for the properties that this transition monitors.
@Nullable Animator
createAnimator(
    @NonNull ViewGroup sceneRoot,
    @Nullable TransitionValues startValues,
    @Nullable TransitionValues endValues
)

This method creates an animation that will be run for this transition given the information in the startValues and endValues structures captured earlier for the start and end scenes.
int

Returns whether appearing and/or disappearing Views are supported.
@Nullable String[]

Returns the set of property names used stored in the TransitionValues object passed into captureStartValues that this transition cares about for the purposes of canceling overlapping animations.
boolean
isTransitionRequired(
    @Nullable TransitionValues startValues,
    @Nullable TransitionValues endValues
)

Returns whether or not the transition should create an Animator, based on the values captured during captureStartValues and captureEndValues.
boolean

Returns whether the view is 'visible' according to the given values object.
@Nullable Animator
onAppear(
    @NonNull ViewGroup sceneRoot,
    @Nullable TransitionValues startValues,
    int startVisibility,
    @Nullable TransitionValues endValues,
    int endVisibility
)

The default implementation of this method does nothing.
@Nullable Animator
onDisappear(
    @NonNull ViewGroup sceneRoot,
    @Nullable TransitionValues startValues,
    int startVisibility,
    @Nullable TransitionValues endValues,
    int endVisibility
)

The default implementation of this method does nothing.
void
setMode(int mode)

Changes the transition to support appearing and/or disappearing Views, depending on mode.

Constants

IN

Added in 1.0.0
public static final int IN = 1

Fading mode used in Fade to make the transition operate on targets that are appearing. Maybe be combined with OUT to fade both in and out.

OUT

Added in 1.0.0
public static final int OUT = 2

Fading mode used in Fade to make the transition operate on targets that are disappearing. Maybe be combined with IN to fade both in and out.

Public constructors

Fade

Added in 1.0.0
public Fade()

Constructs a Fade transition that will fade targets in and out.

Fade

Added in 1.0.0
public Fade(int fadingMode)

Constructs a Fade transition that will fade targets in and/or out, according to the value of fadingMode.

Parameters
int fadingMode

The behavior of this transition, a combination of IN and OUT.

Fade

Added in 1.0.0
public Fade(@NonNull Context context, @NonNull AttributeSet attrs)

Public methods

captureStartValues

public void captureStartValues(@NonNull TransitionValues transitionValues)

Captures the values in the start scene for the properties that this transition monitors. These values are then passed as the startValues structure in a later call to createAnimator. The main concern for an implementation is what the properties are that the transition cares about and what the values are for all of those properties. The start and end values will be compared later during the createAnimator method to determine what, if any, animations, should be run.

Subclasses must implement this method. The method should only be called by the transition system; it is not intended to be called from external classes.

Parameters
@NonNull TransitionValues transitionValues

The holder for any values that the Transition wishes to store. Values are stored in the values field of this TransitionValues object and are keyed from a String value. For example, to store a view's rotation value, a transition might call transitionValues.values.put("appname:transitionname:rotation", view.getRotation()). The target view will already be stored in the transitionValues structure when this method is called.
See also
captureEndValues
createAnimator

isSeekingSupported

public boolean isSeekingSupported()

Returns true if the Transition can be used by controlDelayedTransition. This means that any the state must be ready before any Animator returned by createAnimator has started and if the Animator has ended, it must be able to restore the state when starting in reverse. If a Transition must know when the entire transition has ended, a TransitionListener can be added to getRootTransition and it can listen for onTransitionEnd.

onAppear

public @Nullable Animator onAppear(
    @NonNull ViewGroup sceneRoot,
    @NonNull View view,
    @Nullable TransitionValues startValues,
    @Nullable TransitionValues endValues
)

The default implementation of this method returns a null Animator. Subclasses should override this method to make targets appear with the desired transition. The method should only be called from onAppear.

Parameters
@NonNull ViewGroup sceneRoot

The root of the transition hierarchy
@NonNull View view

The View to make appear. This will be in the target scene's View hierarchy and will be VISIBLE.
@Nullable TransitionValues startValues

The target values in the start scene
@Nullable TransitionValues endValues

The target values in the end scene
Returns
@Nullable Animator

An Animator to be started at the appropriate time in the overall transition for this scene change. A null value means no animation should be run.

onDisappear

public @Nullable Animator onDisappear(
    @NonNull ViewGroup sceneRoot,
    @NonNull View view,
    @Nullable TransitionValues startValues,
    @Nullable TransitionValues endValues
)

The default implementation of this method returns a null Animator. Subclasses should override this method to make targets disappear with the desired transition. The method should only be called from onDisappear.

Parameters
@NonNull ViewGroup sceneRoot

The root of the transition hierarchy
@NonNull View view

The View to make disappear. This will be in the target scene's View hierarchy or in an android.view.ViewGroupOverlay and will be VISIBLE.
@Nullable TransitionValues startValues

The target values in the start scene
@Nullable TransitionValues endValues

The target values in the end scene
Returns
@Nullable Animator

An Animator to be started at the appropriate time in the overall transition for this scene change. A null value means no animation should be run.