Error - Attempt to invoke virtual method 'int android.graphics.Bitmap.getHeight()' on a null object reference

Question

I'm trying to change the height and the width from fixed to match parent or wrap content when images are loaded into the recycler view https://stackoverflow.com/a/67860281/15537898 here is the answer I'm trying to implement but after it gives me this error

Attempt to invoke virtual method 'int android.graphics.Bitmap.getHeight()' on a null object reference

Fragment_Search.java

ShapeableImageView siv;
    Bitmap bm;
    int height = bm.getHeight();
    int width = bm.getWidth();

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_search, container, false);
        requireActivity().setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED);
        postRecyclerView = view.findViewById(R.id.postRecyclerView);
        siv = view.findViewById(R.id.imageView);
        ViewGroup.LayoutParams params = siv.getLayoutParams();
        params.height = height;
        params.width = width;
        postRecyclerView.setLayoutManager(
                new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL)
        );
        params.height = ViewGroup.LayoutParams.WRAP_CONTENT;
        params.width = ViewGroup.LayoutParams.MATCH_PARENT;
        getData();
        mUploads = new ArrayList<>();
        postsAdapter = new PostAdapter_Search(getContext(), mUploads);
        postRecyclerView.setAdapter(postsAdapter);
        return view;
    }

Answer 1

The bitmap varaible (bm) is not initialized, even if you initialize it in onCreateView, you app will still crash because you are trying to get bitmap width and height before the bm variable is even initialized. You can do it this way

@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_search, container, false);
    
    bm = initialize_bitmap_here
    width = bm.getWidth()
    height = bm.getHeght()


    return view;
}