@Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view = inflater.inflate(R.layout.time_configuration_fragment, container, false);
        btAcept = (ImageButton) view.findViewById(R.id.btAcept);
    btAcetp.setVisibility(View.INVISIBLE);



CODE WHEN I INITIALIZED ANIMATION
 @Override
    public void onStopTrackingTouch(SeekBar seekBar) {
        switch (seekBar.getId()) {
          case R.id.seekBarPomodoroTime:
        if (Build.VERSION.SDK_INT >= 21) {
                Utilities.showView(btAcept);
        }
    break;
    }
}