fadeInFadeOutAnimation.java

     Animation fadeIn = new AlphaAnimation(0, 1);
                fadeIn.setInterpolator(new DecelerateInterpolator()); //add this
                fadeIn.setDuration(1500);

                Animation fadeOut = new AlphaAnimation(1, 0);
                fadeOut.setInterpolator(new AccelerateInterpolator()); //and this
                fadeOut.setStartOffset(3000);
                fadeOut.setDuration(1500);

                AnimationSet animation = new AnimationSet(false); //change to false
                animation.addAnimation(fadeIn);
                animation.addAnimation(fadeOut);
                alertView.startAnimation(animation);
                animation.setAnimationListener(new Animation.AnimationListener() {
                    @Override
                    public void onAnimationStart(Animation animation) {
                        alertView.setVisibility(View.VISIBLE);
                    }

                    @Override
                    public void onAnimationEnd(Animation animation) {
                        alertView.setVisibility(View.INVISIBLE);
                    }

                    @Override
                    public void onAnimationRepeat(Animation animation) {

                    }
                });