android firebase yüklemesine göre Buton etkinleştirme ...

Merhaba, Sorum şöyle, Firebase yüklemesine göre butonu aktif etmek istiyorum. eğer yükleme tamamlanmamışsa pasif olmasını istiyorum ama bir türlü yapamadım..Gerekirse Kodarı paylaşabilirim.. İyi günler..

List<Movie> movieList = new ArrayList<>();
    private ImageButton btn_down, btn_fav;
    private Button btn_setter;
    private DatabaseReference movies;
    private IFirebaseLoadDone iFirebaseLoadDone;

    public CartoonFragment() {
        // Required empty public constructor
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view = inflater.inflate(R.layout.fragment_cartoon, container, false);

        movies = FirebaseDatabase.getInstance().getReference("Sports");
        movies.keepSynced(true);
        iFirebaseLoadDone = this;
        loadMovie();

        viewPager2 = view.findViewById(R.id.viewPager2_);

        btn_down = view.findViewById(R.id.btn_down);
        btn_setter = view.findViewById(R.id.btn_setter);
        btn_fav = view.findViewById(R.id.btn_fav);


        btn_down.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

             SaveToGallery();
            }

        });

        btn_setter.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
            }

        });
        btn_fav.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
            }
        });
        return view;
    }

    private void loadMovie() {
        movies.addValueEventListener(this);
    }

    @Override
    public void onFirebaseLoadSuccess(List<Movie> movieList) {
        viewPagerAdapter = new ViewPagerAdapter(getContext(), movieList, viewPager2);
        viewPager2.setAdapter(viewPagerAdapter);
    }

    @Override
    public void onFirebasLoadFailed(String message) {
    }

    @Override
    public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
        for (DataSnapshot moviesSnapShot : dataSnapshot.getChildren())
            movieList.add(moviesSnapShot.getValue(Movie.class));
        Collections.reverse(movieList);
        iFirebaseLoadDone.onFirebaseLoadSuccess(movieList);

        viewPagerAdapter.notifyDataSetChanged();
    }

    @Override
    public void onCancelled(@NonNull DatabaseError databaseError) {
        iFirebaseLoadDone.onFirebasLoadFailed(databaseError.getMessage());
    }

    @Override
    public void onDestroy() {
        movies.removeEventListener(this);
        super.onDestroy();
    }

    @Override
    public void onResume() {
        super.onResume();
    }

    @Override
    public void onStop() {
        movies.removeEventListener(this);
        super.onStop();
    }
}