Android :: Animated Swap Position Of Two Buttons

I am trying to swap the position of two buttons. My swapping code looks as below.
private void exchangeButtons(Button btn1, Button btn2) {
// Create the animation set AnimationSet exchangeAnimation = new AnimationSet(true);
TranslateAnimation translate = new TranslateAnimation(Animation.RELATIVE_TO_SELF, btn2.getLeft(), Animation.RELATIVE_TO_SELF, btn1.getLeft(),
Animation.RELATIVE_TO_SELF, btn2.getRight(), Animation.RELATIVE_TO_SELF, btn1.getRight() );
translate.setDuration(500); exchangeAnimation.addAnimation(translate);
// int fromX = btn1.getLeft();
// int fromY = btn1.getRight();
// int toX = btn2.getLeft();
// int toY = btn2.getRight();

Log.d("ArrangeMe", "view1 pos:" + btn1.getLeft() + ", " +btn1.getRight() + "view2 pos:" + btn2.getLeft() + ", " + btn2.getRight());
AnimationSet exchangeAnimation1 = new AnimationSet(true);
TranslateAnimation translate1 = new TranslateAnimation(Animation.RELATIVE_TO_SELF, btn1.getLeft(), Animation.RELATIVE_TO_SELF, btn2.getLeft(),
Animation.RELATIVE_TO_SELF, btn1.getRight(), Animation.RELATIVE_TO_SELF, btn2.getRight());
translate1.setDuration(500); exchangeAnimation1.addAnimation(translate1);
// EXECUTE
btn1.startAnimation(exchangeAnimation);
btn2.startAnimation(exchangeAnimation1); }

I call the code as below:
exchangeButtons(button1, button2);
My layout looks as below:
what happens when I execute the code is, instead of the buttons exchanging their positions, they just disappear for sometime[may be 500 ms] and reappear as they were originally.