Added in API level 21

ChangeTransform


open class ChangeTransform : Transition
kotlin.Any
   ↳ android.transition.Transition
   ↳ android.transition.ChangeTransform

This Transition captures scale and rotation for Views before and after the scene change and animates those changes during the transition. A change in parent is handled as well by capturing the transforms from the parent before and after the scene change and animating those during the transition.

Summary

Inherited constants
Public constructors

ChangeTransform(context: Context!, attrs: AttributeSet!)

Public methods
open Unit
captureEndValues(transitionValues: TransitionValues!)

open Unit

open Animator?
createAnimator(sceneRoot: ViewGroup, startValues: TransitionValues?, 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.

open Boolean

Returns whether parent changes will be tracked by the ChangeTransform.

open Boolean

Returns whether changes to parent should use an overlay or not.

open Array<String!>!

open Unit
setReparent(reparent: Boolean)

Sets whether parent changes will be tracked by the ChangeTransform.

open Unit
setReparentWithOverlay(reparentWithOverlay: Boolean)

Sets whether changes to parent should use an overlay or not.

Inherited functions

Public constructors

ChangeTransform

Added in API level 21
ChangeTransform()

ChangeTransform

Added in API level 21
ChangeTransform(
    context: Context!,
    attrs: AttributeSet!)

Public methods

captureEndValues

Added in API level 21
open fun captureEndValues(transitionValues: TransitionValues!): Unit
Parameters
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.

captureStartValues

Added in API level 21
open fun captureStartValues(transitionValues: TransitionValues!): Unit
Parameters
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.

createAnimator

Added in API level 21
open fun createAnimator(
    sceneRoot: ViewGroup,
    startValues: TransitionValues?,
    endValues: TransitionValues?
): Animator?

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.

Parameters
sceneRoot ViewGroup: This value cannot be null.
startValues TransitionValues?: This value may be null.
endValues TransitionValues?: This value may be null.
Return
Animator? This value may be null.

getReparent

Added in API level 21
open fun getReparent(): Boolean

Returns whether parent changes will be tracked by the ChangeTransform. If parent changes are tracked, then the transform will adjust to the transforms of the different parents. If they aren't tracked, only the transforms of the transitioning view will be tracked. Default is true.

Return
Boolean whether parent changes will be tracked by the ChangeTransform.

getReparentWithOverlay

Added in API level 21
open fun getReparentWithOverlay(): Boolean

Returns whether changes to parent should use an overlay or not. When the parent change doesn't use an overlay, it affects the transforms of the child. The default value is true.

Note: when Overlays are not used when a parent changes, a view can be clipped when it moves outside the bounds of its parent. Setting android.view.ViewGroup#setClipChildren(boolean) and android.view.ViewGroup#setClipToPadding(boolean) can help. Also, when Overlays are not used and the parent is animating its location, the position of the child view will be relative to its parent's final position, so it may appear to "jump" at the beginning.

Return
Boolean true when a changed parent should execute the transition inside the scene root's overlay or false if a parent change only affects the transform of the transitioning view.

getTransitionProperties

Added in API level 21
open fun getTransitionProperties(): Array<String!>!
Return
Array<String!>! An array of property names as described in the class documentation for TransitionValues. The default implementation returns null.

setReparent

Added in API level 21
open fun setReparent(reparent: Boolean): Unit

Sets whether parent changes will be tracked by the ChangeTransform. If parent changes are tracked, then the transform will adjust to the transforms of the different parents. If they aren't tracked, only the transforms of the transitioning view will be tracked. Default is true.

Parameters
reparent Boolean: Set to true to track parent changes or false to only track changes of the transitioning view without considering the parent change.

setReparentWithOverlay

Added in API level 21
open fun setReparentWithOverlay(reparentWithOverlay: Boolean): Unit

Sets whether changes to parent should use an overlay or not. When the parent change doesn't use an overlay, it affects the transforms of the child. The default value is true.

Note: when Overlays are not used when a parent changes, a view can be clipped when it moves outside the bounds of its parent. Setting android.view.ViewGroup#setClipChildren(boolean) and android.view.ViewGroup#setClipToPadding(boolean) can help. Also, when Overlays are not used and the parent is animating its location, the position of the child view will be relative to its parent's final position, so it may appear to "jump" at the beginning.

Parameters
reparentWithOverlay Boolean: true when a changed parent should execute the transition inside the scene root's overlay or false if a parent change only affects the transform of the transitioning view.