Java tutorial
//package com.java2s; import android.animation.ObjectAnimator; import android.view.View; import android.view.animation.AccelerateDecelerateInterpolator; public class Main { public static void arrowDownAnim(View view) { ObjectAnimator animator = ObjectAnimator.ofFloat(view, "rotation", 180f, 0f); animator.setDuration(400); animator.setInterpolator(new AccelerateDecelerateInterpolator()); animator.start(); } }