Not Working!!

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        setEnterTransition();
        setExitTransition();
      
    }

    @TargetApi(21)
    private void setEnterTransition(){

        Fade fade_transition = new Fade();
        fade_transition.setDuration(1000);
        getWindow().setEnterTransition(fade_transition);
    }

    @TargetApi(21)
    private void setExitTransition(){

        Slide slide_transition = new Slide();
        slide_transition.setDuration(1000);
        getWindow().setExitTransition(slide_transition);
    }