TransitionManager

Artifact: androidx.transition:transition

Added in 1.0.0

Kotlin |Java

class TransitionManager

This class manages the set of transitions that fire when there is a change of Scene. To use the manager, add scenes along with transition objects with calls to setTransition or setTransition. Setting specific transitions for scene changes is not required; by default, a Scene change will use AutoTransition to do something reasonable for most situations. Specifying other transitions for particular scene changes is only necessary if the application wants different transition behavior in these situations.

TransitionManagers can be declared in XML resource files inside the res/transition directory. TransitionManager resources consist of the transitionManagertag name, containing one or more transition tags, each of which describe the relationship of that transition to the from/to scene information in that tag. For example, here is a resource file that declares several scene transitions:

    <transitionManager xmlns:android="http://schemas.android.com/apk/res/android">
        <transition android:fromScene="@layout/transition_scene1"
                    android:toScene="@layout/transition_scene2"
                    android:transition="@transition/changebounds"/>
        <transition android:fromScene="@layout/transition_scene2"
                    android:toScene="@layout/transition_scene1"
                    android:transition="@transition/changebounds"/>
        <transition android:toScene="@layout/transition_scene3"
                    android:transition="@transition/changebounds_fadein_together"/>
        <transition android:fromScene="@layout/transition_scene3"
                    android:toScene="@layout/transition_scene1"
                    android:transition="@transition/changebounds_fadeout_sequential"/>
        <transition android:fromScene="@layout/transition_scene3"
                    android:toScene="@layout/transition_scene2"
                    android:transition="@transition/changebounds_fadeout_sequential"/>
    </transitionManager>

For each of the fromScene and toScene attributes, there is a reference to a standard XML layout file. This is equivalent to creating a scene from a layout in code by calling getSceneForLayout. For the transition attribute, there is a reference to a resource file in the res/transition directory which describes that transition.

Summary

Public constructors
`TransitionManager()`

Public functions
`java-static Unit`	`beginDelayedTransition(sceneRoot: ViewGroup)` Convenience method to animate, using the default transition, to a new scene defined by all changes within the given scene root between calling this method and the next rendering frame.
`java-static Unit`	`beginDelayedTransition(sceneRoot: ViewGroup, transition: Transition?)` Convenience method to animate to a new scene defined by all changes within the given scene root between calling this method and the next rendering frame.
`java-static TransitionSeekController?`	`controlDelayedTransition(sceneRoot: ViewGroup, transition: Transition)` Create a `TransitionSeekController` to allow seeking an animation to a new scene defined by all changes within the given scene root between calling this method and the next rendered frame.
`java-static TransitionSeekController?`	`createSeekController(scene: Scene, transition: Transition)` Convenience method to seek to the given scene using the given transition.
`java-static Unit`	`endTransitions(sceneRoot: ViewGroup?)` Ends all pending and ongoing transitions on the specified scene root.
`java-static Unit`	`go(scene: Scene)` Convenience method to simply change to the given scene using the default transition for TransitionManager.
`java-static Unit`	`go(scene: Scene, transition: Transition?)` Convenience method to simply change to the given scene using the given transition.
`Unit`	`setTransition(scene: Scene, transition: Transition?)` Sets a specific transition to occur when the given scene is entered.
`Unit`	`setTransition(fromScene: Scene, toScene: Scene, transition: Transition?)` Sets a specific transition to occur when the given pair of scenes is exited/entered.
`Unit`	`transitionTo(scene: Scene)` Change to the given scene, using the appropriate transition for this particular scene change (as specified to the TransitionManager, or the default if no such transition exists).

Public constructors

TransitionManager

Added in 1.0.0

TransitionManager()

Public functions

beginDelayedTransition

Added in 1.0.0

java-static fun beginDelayedTransition(sceneRoot: ViewGroup): Unit

Convenience method to animate, using the default transition, to a new scene defined by all changes within the given scene root between calling this method and the next rendering frame. Equivalent to calling beginDelayedTransition with a value of null for the transition parameter.

Parameters
`sceneRoot: ViewGroup`	The root of the View hierarchy to run the transition on.

beginDelayedTransition

Added in 1.0.0

java-static fun beginDelayedTransition(sceneRoot: ViewGroup, transition: Transition?): Unit

Convenience method to animate to a new scene defined by all changes within the given scene root between calling this method and the next rendering frame. Calling this method causes TransitionManager to capture current values in the scene root and then post a request to run a transition on the next frame. At that time, the new values in the scene root will be captured and changes will be animated. There is no need to create a Scene; it is implied by changes which take place between calling this method and the next frame when the transition begins.

Calling this method several times before the next frame (for example, if unrelated code also wants to make dynamic changes and run a transition on the same scene root), only the first call will trigger capturing values and exiting the current scene. Subsequent calls to the method with the same scene root during the same frame will be ignored.

Passing in null for the transition parameter will cause the TransitionManager to use its default transition.

Parameters
`sceneRoot: ViewGroup`	The root of the View hierarchy to run the transition on.
`transition: Transition?`	The transition to use for this change. A value of null causes the TransitionManager to use the default transition.

controlDelayedTransition

Added in 1.5.0

java-static fun controlDelayedTransition(sceneRoot: ViewGroup, transition: Transition): TransitionSeekController?

Create a TransitionSeekController to allow seeking an animation to a new scene defined by all changes within the given scene root between calling this method and the next rendered frame. Calling this method causes TransitionManager to capture current values in the scene root and then post a request to run a transition on the next frame. At that time, the new values in the scene root will be captured and changes will be animated. There is no need to create a Scene; it is implied by changes which take place between calling this method and the next frame when the transition begins.

Parameters
`sceneRoot: ViewGroup`	The root of the View hierarchy to run the transition on.
`transition: Transition`	The transition to use for this change.

Returns
`TransitionSeekController?`	a `TransitionSeekController` that can be used control the animation to the destination scene. `null` is returned when seeking is not supported on the scene, either because it is running on `TIRAMISU` or earlier, another Transition is being captured for `sceneRoot`, or `sceneRoot` hasn't had a layout yet.

Throws
`java.lang.IllegalArgumentException`	if `transition` returns `false` from `isSeekingSupported`.

createSeekController

Added in 1.5.0

java-static fun createSeekController(scene: Scene, transition: Transition): TransitionSeekController?

Convenience method to seek to the given scene using the given transition. If seeking is not supported because the device is Build.VERSION_CODES.TIRAMISU or earlier, the scene transition is immediate and null is returned.

Parameters
`scene: Scene`	The Scene to change to
`transition: Transition`	The transition to use for this scene change.

Returns
`TransitionSeekController?`	a `TransitionSeekController` that can be used control the animation to the destination scene. `null` is returned when seeking is not supported on the scene, either because it is running on android.os.Build.VERSION_CODES.TIRAMISU or earlier, another Transition is being captured for `sceneRoot`, or `sceneRoot` hasn't had a layout yet.

Throws
`java.lang.IllegalArgumentException`	if `transition` returns `false` from `isSeekingSupported`.

endTransitions

Added in 1.0.0

java-static fun endTransitions(sceneRoot: ViewGroup?): Unit

Ends all pending and ongoing transitions on the specified scene root.

Parameters
`sceneRoot: ViewGroup?`	The root of the View hierarchy to end transitions on.

go

Added in 1.0.0

java-static fun go(scene: Scene): Unit

Convenience method to simply change to the given scene using the default transition for TransitionManager.

Parameters
`scene: Scene`	The Scene to change to

go

Added in 1.0.0

java-static fun go(scene: Scene, transition: Transition?): Unit

Convenience method to simply change to the given scene using the given transition.

Passing in null for the transition parameter will result in the scene changing without any transition running, and is equivalent to calling exit on the scene root's current scene, followed by enter on the scene specified by the scene parameter.

Parameters
`scene: Scene`	The Scene to change to
`transition: Transition?`	The transition to use for this scene change. A value of null causes the scene change to happen with no transition.

setTransition

Added in 1.0.0

fun setTransition(scene: Scene, transition: Transition?): Unit

Sets a specific transition to occur when the given scene is entered.

Parameters
`scene: Scene`	The scene which, when applied, will cause the given transition to run.
`transition: Transition?`	The transition that will play when the given scene is entered. A value of null will result in the default behavior of using the default transition instead.

setTransition

Added in 1.0.0

fun setTransition(fromScene: Scene, toScene: Scene, transition: Transition?): Unit

Sets a specific transition to occur when the given pair of scenes is exited/entered.

Parameters
`fromScene: Scene`	The scene being exited when the given transition will be run
`toScene: Scene`	The scene being entered when the given transition will be run
`transition: Transition?`	The transition that will play when the given scene is entered. A value of null will result in the default behavior of using the default transition instead.

transitionTo

Added in 1.0.0

fun transitionTo(scene: Scene): Unit

Change to the given scene, using the appropriate transition for this particular scene change (as specified to the TransitionManager, or the default if no such transition exists).

Parameters
`scene: Scene`	The Scene to change to