TransitionSet

Kotlin |Java

open class TransitionSet : Transition

kotlin.Any
↳	androidx.transition.Transition
	↳	androidx.transition.TransitionSet

Known Direct Subclasses AutoTransition AutoTransition Utility class for creating a default transition that automatically fades, moves, and resizes views during a scene change.

A TransitionSet is a parent of child transitions (including other TransitionSets). Using TransitionSets enables more complex choreography of transitions, where some sets play ORDERING_TOGETHER and others play ORDERING_SEQUENTIAL. For example, AutoTransition uses a TransitionSet to sequentially play a Fade(Fade.OUT), followed by a ChangeBounds, followed by a Fade(Fade.OUT) transition.

A TransitionSet can be described in a resource file by using the tag transitionSet, along with the standard attributes of TransitionSet and Transition. Child transitions of the TransitionSet object can be loaded by adding those child tags inside the enclosing transitionSet tag. For example, the following xml describes a TransitionSet that plays a Fade and then a ChangeBounds transition on the affected view targets:

<transitionSet xmlns:android="http://schemas.android.com/apk/res/android"
              android:transitionOrdering="sequential">
          <fade/>
          <changeBounds/>
      </transitionSet>
  

Summary

Constants
static Int	ORDERING_SEQUENTIAL A flag used to indicate that the child transitions of this set should play in sequence; when one child transition ends, the next child transition begins.
static Int	ORDERING_TOGETHER A flag used to indicate that the child transitions of this set should all start at the same time.

Inherited constants

From class Transition Int MATCH_ID With setMatchOrder(int...), chooses to match by android.view.View#getId(). Negative IDs will not be matched. Int MATCH_INSTANCE With setMatchOrder(int...), chooses to match by View instance. Int MATCH_ITEM_ID With setMatchOrder(int...), chooses to match by the android.widget.Adapter item id. When android.widget.Adapter#hasStableIds() returns false, no match will be made for items. Int MATCH_NAME With setMatchOrder(int...), chooses to match by android.view.View#getTransitionName(). Null names will not be matched.

Public constructors
<init>() Constructs an empty transition set.
<init>(@NonNull context: Context, @NonNull attrs: AttributeSet)

Public methods
open TransitionSet	addListener(@NonNull listener: Transition.TransitionListener)
open TransitionSet	addTarget(@NonNull target: View)
open TransitionSet	addTarget(@IdRes targetId: Int)
open TransitionSet	addTarget(@NonNull targetName: String)
open TransitionSet	addTarget(@NonNull targetType: Class<*>)
open TransitionSet	addTransition(@NonNull transition: Transition) Adds child transition to this set.
open Unit	captureEndValues(@NonNull transitionValues: TransitionValues)
open Unit	captureStartValues(@NonNull transitionValues: TransitionValues)
open Transition	clone()
open Transition	excludeTarget(@NonNull target: View, exclude: Boolean)
open Transition	excludeTarget(@NonNull targetName: String, exclude: Boolean)
open Transition	excludeTarget(targetId: Int, exclude: Boolean)
open Transition	excludeTarget(@NonNull type: Class<*>, exclude: Boolean)
open Int	getOrdering() Returns the ordering of this TransitionSet.
open Transition?	getTransitionAt(index: Int) Returns the child Transition at the specified position in the TransitionSet.
open Int	getTransitionCount() Returns the number of child transitions in the TransitionSet.
open TransitionSet	removeListener(@NonNull listener: Transition.TransitionListener)
open TransitionSet	removeTarget(@IdRes targetId: Int)
open TransitionSet	removeTarget(@NonNull target: View)
open TransitionSet	removeTarget(@NonNull target: Class<*>)
open TransitionSet	removeTarget(@NonNull target: String)
open TransitionSet	removeTransition(@NonNull transition: Transition) Removes the specified child transition from this set.
open TransitionSet	setDuration(duration: Long) Setting a non-negative duration on a TransitionSet causes all of the child transitions (current and future) to inherit this duration.
open Unit	setEpicenterCallback(epicenterCallback: Transition.EpicenterCallback?)
open TransitionSet	setInterpolator(@Nullable interpolator: TimeInterpolator?)
open TransitionSet	setOrdering(ordering: Int) Sets the play order of this set's child transitions.
open Unit	setPathMotion(pathMotion: PathMotion?)
open Unit	setPropagation(propagation: TransitionPropagation?)
open TransitionSet	setStartDelay(startDelay: Long)

Inherited functions

From class Transition Animator? createAnimator(@NonNull sceneRoot: ViewGroup, @Nullable startValues: TransitionValues?, @Nullable endValues: TransitionValues?) 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. Subclasses of Transition should override this method. The method should only be called by the transition system; it is not intended to be called from external classes. This method is called by the transition's parent (all the way up to the topmost Transition in the hierarchy) with the sceneRoot and start/end values that the transition may need to set up initial target values and construct an appropriate animation. For example, if an overall Transition is a TransitionSet consisting of several child transitions in sequence, then some of the child transitions may want to set initial values on target views prior to the overall Transition commencing, to put them in an appropriate state for the delay between that start and the child Transition start time. For example, a transition that fades an item in may wish to set the starting alpha value to 0, to avoid it blinking in prior to the transition actually starting the animation. This is necessary because the scene change that triggers the Transition will automatically set the end-scene on all target views, so a Transition that wants to animate from a different value should set that value prior to returning from this method. Additionally, a Transition can perform logic to determine whether the transition needs to run on the given target and start/end values. For example, a transition that resizes objects on the screen may wish to avoid running for views which are not present in either the start or end scenes. If there is an animator created and returned from this method, the transition mechanism will apply any applicable duration, startDelay, and interpolator to that animation and start it. A return value of null indicates that no animation should run. The default implementation returns null. The method is called for every applicable target object, which is stored in the TransitionValues#view field. Transition excludeChildren(@NonNull target: View, exclude: Boolean) Whether to add the children of given target to the list of target children to exclude from this transition. The exclude parameter specifies whether the target should be added to or removed from the excluded list. Excluding targets is a general mechanism for allowing transitions to run on a view hierarchy while skipping target views that should not be part of the transition. For example, you may want to avoid animating children of a specific ListView or Spinner. Views can be excluded either by their id, or by their instance reference, or by the Class of that view (eg, Spinner). Transition excludeChildren(@IdRes targetId: Int, exclude: Boolean) Whether to add the children of the given id to the list of targets to exclude from this transition. The exclude parameter specifies whether the children of the target should be added to or removed from the excluded list. Excluding children in this way provides a simple mechanism for excluding all children of specific targets, rather than individually excluding each child individually. Excluding targets is a general mechanism for allowing transitions to run on a view hierarchy while skipping target views that should not be part of the transition. For example, you may want to avoid animating children of a specific ListView or Spinner. Views can be excluded either by their id, or by their instance reference, or by the Class of that view (eg, Spinner). Transition excludeChildren(@NonNull type: Class<*>, exclude: Boolean) Whether to add the given type to the list of types whose children should be excluded from this transition. The exclude parameter specifies whether the target type should be added to or removed from the excluded list. Excluding targets is a general mechanism for allowing transitions to run on a view hierarchy while skipping target views that should not be part of the transition. For example, you may want to avoid animating children of a specific ListView or Spinner. Views can be excluded either by their id, or by their instance reference, or by the Class of that view (eg, Spinner). Long getDuration() Returns the duration set on this transition. If no duration has been set, the returned value will be negative, indicating that resulting animators will retain their own durations. Rect? getEpicenter() Returns the epicenter as specified by the android.transition.Transition.EpicenterCallback or null if no callback exists. Transition.EpicenterCallback? getEpicenterCallback() Returns the callback used to find the epicenter of the Transition. Transitions like android.transition.Explode use a point or Rect to orient the direction of travel. This is called the epicenter of the Transition and is typically centered on a touched View. The android.transition.Transition.EpicenterCallback allows a Transition to dynamically retrieve the epicenter during a Transition. TimeInterpolator? getInterpolator() Returns the interpolator set on this transition. If no interpolator has been set, the returned value will be null, indicating that resulting animators will retain their own interpolators. String getName() Returns the name of this Transition. This name is used internally to distinguish between different transitions to determine when interrupting transitions overlap. For example, a ChangeBounds running on the same target view as another ChangeBounds should determine whether the old transition is animating to different end values and should be canceled in favor of the new transition. By default, a Transition's name is simply the value of Class#getName(), but subclasses are free to override and return something different. PathMotion getPathMotion() Returns the algorithm object used to interpolate along two dimensions. This is typically used to determine the View motion between two points. TransitionPropagation? getPropagation() Returns the android.transition.TransitionPropagation used to calculate Animator start delays. When a Transition affects several Views like android.transition.Explode or android.transition.Slide, there may be a desire to have a "wave-front" effect such that the Animator start delay depends on position of the View. The TransitionPropagation specifies how the start delays are calculated. Long getStartDelay() Returns the startDelay set on this transition. If no startDelay has been set, the returned value will be negative, indicating that resulting animators will retain their own startDelays. MutableList<Int!> getTargetIds() Returns the array of target IDs that this transition limits itself to tracking and animating. If the array is null for both this method and getTargets(), then this transition is not limited to specific views, and will handle changes to any views in the hierarchy of a scene change. MutableList<String!>? getTargetNames() Returns the list of target transitionNames that this transition limits itself to tracking and animating. If the list is null or empty for getTargetIds(), getTargets(), getTargetNames(), and getTargetTypes() then this transition is not limited to specific views, and will handle changes to any views in the hierarchy of a scene change. MutableList<Class<*>!>? getTargetTypes() Returns the list of target transitionNames that this transition limits itself to tracking and animating. If the list is null or empty for getTargetIds(), getTargets(), getTargetNames(), and getTargetTypes() then this transition is not limited to specific views, and will handle changes to any views in the hierarchy of a scene change. MutableList<View!> getTargets() Returns the array of target views that this transition limits itself to tracking and animating. If the array is null for both this method and getTargetIds(), then this transition is not limited to specific views, and will handle changes to any views in the hierarchy of a scene change. Array<String!>? getTransitionProperties() Returns the set of property names used stored in the TransitionValues object passed into captureStartValues(TransitionValues) that this transition cares about for the purposes of canceling overlapping animations. When any transition is started on a given scene root, all transitions currently running on that same scene root are checked to see whether the properties on which they based their animations agree with the end values of the same properties in the new transition. If the end values are not equal, then the old animation is canceled since the new transition will start a new animation to these new values. If the values are equal, the old animation is allowed to continue and no new animation is started for that transition. A transition does not need to override this method. However, not doing so will mean that the cancellation logic outlined in the previous paragraph will be skipped for that transition, possibly leading to artifacts as old transitions and new transitions on the same targets run in parallel, animating views toward potentially different end values. TransitionValues? getTransitionValues(@NonNull view: View, start: Boolean) This method can be called by transitions to get the TransitionValues for any particular view during the transition-playing process. This might be necessary, for example, to query the before/after state of related views for a given transition. Boolean isTransitionRequired(@Nullable startValues: TransitionValues?, @Nullable endValues: TransitionValues?) Returns whether or not the transition should create an Animator, based on the values captured during captureStartValues(TransitionValues) and captureEndValues(TransitionValues). The default implementation compares the property values returned from getTransitionProperties(), or all property values if getTransitionProperties() returns null. Subclasses may override this method to provide logic more specific to the transition implementation. Unit setMatchOrder(vararg matches: Int) Sets the order in which Transition matches View start and end values. The default behavior is to match first by android.view.View#getTransitionName(), then by View instance, then by android.view.View#getId() and finally by its item ID if it is in a direct child of ListView. The caller can choose to have only some or all of the values of MATCH_INSTANCE, MATCH_NAME, MATCH_ITEM_ID, and MATCH_ID. Only the match algorithms supplied will be used to determine whether Views are the the same in both the start and end Scene. Views that do not match will be considered as entering or leaving the Scene. String toString()

Constants

ORDERING_SEQUENTIAL

static val ORDERING_SEQUENTIAL: Int

A flag used to indicate that the child transitions of this set should play in sequence; when one child transition ends, the next child transition begins. Note that a transition does not end until all instances of it (which are playing on all applicable targets of the transition) end.

Value: 1

ORDERING_TOGETHER

static val ORDERING_TOGETHER: Int

A flag used to indicate that the child transitions of this set should all start at the same time.

Value: 0

Public constructors

<init>

TransitionSet()

Constructs an empty transition set. Add child transitions to the set by calling addTransition(Transition) )}. By default, child transitions will play together.

<init>

TransitionSet(
    @NonNull context: Context, 
    @NonNull attrs: AttributeSet)

Public methods

addListener

@NonNull open fun addListener(@NonNull listener: Transition.TransitionListener): TransitionSet

addTarget

@NonNull open fun addTarget(@NonNull target: View): TransitionSet

addTarget

@NonNull open fun addTarget(@IdRes targetId: Int): TransitionSet

addTarget

@NonNull open fun addTarget(@NonNull targetName: String): TransitionSet

addTarget

@NonNull open fun addTarget(@NonNull targetType: Class<*>): TransitionSet

addTransition

@NonNull open fun addTransition(@NonNull transition: Transition): TransitionSet

Adds child transition to this set. The order in which this child transition is added relative to other child transitions that are added, in addition to the ordering property, determines the order in which the transitions are started.

If this transitionSet has a duration, interpolator, propagation delay, path motion, or epicenter callback set on it, the child transition will inherit the values that are set. Transitions are assumed to have a maximum of one transitionSet parent.

Parameters
transition	Transition: A non-null child transition to be added to this set.

Return
TransitionSet	This transitionSet object.

captureEndValues

open fun captureEndValues(@NonNull transitionValues: TransitionValues): Unit

captureStartValues

open fun captureStartValues(@NonNull transitionValues: TransitionValues): Unit

clone

open fun clone(): Transition

excludeTarget

@NonNull open fun excludeTarget(
    @NonNull target: View, 
    exclude: Boolean
): Transition

excludeTarget

@NonNull open fun excludeTarget(
    @NonNull targetName: String, 
    exclude: Boolean
): Transition

excludeTarget

@NonNull open fun excludeTarget(
    targetId: Int, 
    exclude: Boolean
): Transition

excludeTarget

@NonNull open fun excludeTarget(
    @NonNull type: Class<*>, 
    exclude: Boolean
): Transition

getOrdering

open fun getOrdering(): Int

Returns the ordering of this TransitionSet. By default, the value is ORDERING_TOGETHER.

Return
Int	ORDERING_TOGETHER if child transitions will play at the same time, ORDERING_SEQUENTIAL if they will play in sequence.

See Also

• #setOrdering(int)

getTransitionAt

@Nullable open fun getTransitionAt(index: Int): Transition?

Returns the child Transition at the specified position in the TransitionSet.

Parameters
index	Int: The position of the Transition to retrieve.

See Also

• #addTransition(Transition)
• #getTransitionCount()

getTransitionCount

open fun getTransitionCount(): Int

Returns the number of child transitions in the TransitionSet.

Return
Int	The number of child transitions in the TransitionSet.

See Also

• #addTransition(Transition)
• #getTransitionAt(int)

removeListener

@NonNull open fun removeListener(@NonNull listener: Transition.TransitionListener): TransitionSet

removeTarget

@NonNull open fun removeTarget(@IdRes targetId: Int): TransitionSet

removeTarget

@NonNull open fun removeTarget(@NonNull target: View): TransitionSet

removeTarget

@NonNull open fun removeTarget(@NonNull target: Class<*>): TransitionSet

removeTarget

@NonNull open fun removeTarget(@NonNull target: String): TransitionSet

removeTransition

@NonNull open fun removeTransition(@NonNull transition: Transition): TransitionSet

Removes the specified child transition from this set.

Parameters
transition	Transition: The transition to be removed.

Return
TransitionSet	This transitionSet object.

setDuration

@NonNull open fun setDuration(duration: Long): TransitionSet

Setting a non-negative duration on a TransitionSet causes all of the child transitions (current and future) to inherit this duration.

Parameters
duration	Long: The length of the animation, in milliseconds.

Return
TransitionSet	This transitionSet object.

setEpicenterCallback

open fun setEpicenterCallback(epicenterCallback: Transition.EpicenterCallback?): Unit

setInterpolator

@NonNull open fun setInterpolator(@Nullable interpolator: TimeInterpolator?): TransitionSet

setOrdering

@NonNull open fun setOrdering(ordering: Int): TransitionSet

Sets the play order of this set's child transitions.

Parameters
ordering	Int: ORDERING_TOGETHER to play this set's child transitions together, ORDERING_SEQUENTIAL to play the child transitions in sequence.

Return
TransitionSet	This transitionSet object.

setPathMotion

open fun setPathMotion(pathMotion: PathMotion?): Unit

setPropagation

open fun setPropagation(propagation: TransitionPropagation?): Unit

setStartDelay

@NonNull open fun setStartDelay(startDelay: Long): TransitionSet