CircularRevealExample.kt

 private fun animationOpenNewTask() {
        if (!isNewTaskOpened) {

            val x = addTaskButton.x.toInt() + addTaskButton.width / 2
            val y = addTaskButton.y.toInt() + addTaskButton.height / 2

            val startRadius = 0.0f
            val endRadius = (Math.hypot(
                overlayFragmentContainer.width.toDouble(),
                overlayFragmentContainer.height.toDouble()
            )).toFloat()

            val anim =
                ViewAnimationUtils.createCircularReveal(overlayFragmentContainer, x, y, startRadius, endRadius).apply {
                    interpolator = FastOutLinearInInterpolator()
                    duration = 800
                    addListener(object : AnimatorListenerAdapter {
                        override fun onAnimationStart(animation: Animator?) {
                            overlayFragmentContainer.visibility = View.VISIBLE
                        }
                    })
                }
            
            anim.start()
            isNewTaskOpened = true
        } else {

            val x = addTaskButton.x.toInt() + addTaskButton.width / 2
            val y = addTaskButton.y.toInt() + addTaskButton.height / 2

            val startRadius = (Math.hypot(
                overlayFragmentContainer.width.toDouble(),
                overlayFragmentContainer.height.toDouble()
            )).toFloat()
            val endRadius = 0.0f

            val anim =
                ViewAnimationUtils.createCircularReveal(overlayFragmentContainer, x, y, startRadius, endRadius).apply {
                    interpolator = FastOutLinearInInterpolator()
                    duration = 500
                }
            anim.addListener(object : AnimatorListenerAdapter {
                override fun onAnimationEnd(animation: Animator?) {
                    overlayFragmentContainer.visibility = View.INVISIBLE
                }

            })

            anim.start()
            isNewTaskOpened = false
        }
    }