49.12 Starting an Animation from Code

So far in this chapter we have only looked at controlling an animation using the OnSwipe and OnClick handlers. It is also possible to start an animation from within code by calling methods on the MotionLayout instance. The following code, for example, runs the transition from start to end with a duration of 2000ms for a layout named motionLayout:

motionLayout.setTransitionDuration(2000)

motionLayout.transitionToEnd()

In the absence of addition settings, the start and end states used for the animation will be those declared in the Transition declaration of the MotionScene file. To use specific start and end constraint sets, simply reference them by id in a call to the setTransition() method of the MotionLayout instance:

motionLayout.setTransition(R.id.myStart, R.id.myEnd)

motionLayout.transitionToEnd()

To monitor the state of an animation while it is running, add a transition listener to the MotionLayout instance as follows:

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