[FIXED] How to repeat Android Animation

Issue

I'm trying to get two views to move to the middle of the screen and bounce back again x number of times.

This code does that but it runs only once. ` val view = findViewById(R.id.imageView2)

    val animation = SpringAnimation(view, DynamicAnimation.TRANSLATION_Y, 0f)

    val view2 = findViewById<View>(R.id.imageView3)
    val animation2 = SpringAnimation(view2, DynamicAnimation.TRANSLATION_Y, 0f)

    findViewById<View>(R.id.imageView2).also { img ->
        SpringAnimation(img, DynamicAnimation.TRANSLATION_Y).apply {

            animation.getSpring().setDampingRatio(SpringForce.DAMPING_RATIO_HIGH_BOUNCY)

          
            animation.spring.stiffness = SpringForce.STIFFNESS_VERY_LOW

                animation.animateToFinalPosition(50f)
            

        }
    }
    findViewById<View>(R.id.imageView3).also { img ->
        SpringAnimation(img, DynamicAnimation.TRANSLATION_Y).apply {
            
            animation2.getSpring().setDampingRatio(SpringForce.DAMPING_RATIO_HIGH_BOUNCY)

            
            animation2.spring.stiffness = SpringForce.STIFFNESS_VERY_LOW
           
            animation2.animateToFinalPosition(-100f)
            

        }
    }`

So how do I get it to run x number of times? This is obviously Spring Animation, but I'm not married to it. If there is another animation that would accomplish this I'd be totally open to changing.

Solution

You can run multiple SpringAnimations on the same View by repeatedly calling animateToFinalPosition(translation) with a sequence of translation values.

For example:

startSpringAnimations(findViewById<View>(R.id.imageView1), 300f, 6)
startSpringAnimations(findViewById<View>(R.id.imageView2), -600f, 6)

with a function

/**
 * [view] will be moved using [times] SpringAnimations over a distance of abs([totalTranslation])
 * If [totalTranslation] is negative, direction will be up, else down
 */
private fun startSpringAnimations(view: View, totalTranslation: Float, times: Int ) {
    if(times <= 0){
        return
    }

    val translation = totalTranslation/ times.toFloat()

    SpringAnimation(view, DynamicAnimation.TRANSLATION_Y, 0f).apply{
        spring.dampingRatio = SpringForce.DAMPING_RATIO_HIGH_BOUNCY
        spring.stiffness = SpringForce.STIFFNESS_VERY_LOW

        addEndListener(object: DynamicAnimation.OnAnimationEndListener{
            private var count = 1
            override fun onAnimationEnd(animation1: DynamicAnimation<*>?, canceled: Boolean, value: Float, velocity: Float) {
                Log.d("SpringAnimation", "onAnimationEnd: animation $animation1 canceled $canceled value $value velocity $velocity count $count")
                if (canceled) return

                count++
                if(count <= times){
                    animateToFinalPosition(translation * count)
                }
            }
        })
        animateToFinalPosition(translation)
    }
}

Answered By - Bö macht Blau
Answer Checked By - Clifford M. (JavaFixing Volunteer)