ImageView img= (ImageView) findViewById(R.id.image);
img.setImageResource(R.drawable.my_image);

Attempt to invoke virtual method 'android.view.View android.widget.ImageView.findViewById(int)' on a null object reference

java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.ImageView.setImageDrawable(android.graphics.drawable.Drawable)'

<ImageView
    android:id="@+id/cafe"
    android:layout_width="100dp"
    android:layout_height="90dp"
    android:layout_alignParentEnd="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentTop="true"
    android:layout_gravity="right"
    android:src="@drawable/cafe" />

<ImageView
    android:id="@+id/baron"
    android:layout_width="100dp"
    android:layout_height="90dp"
    android:layout_alignParentEnd="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentTop="true"
    android:layout_gravity="right"
    android:src="@drawable/bar" />

public boolean onMarkerClick(final Marker marker) {

ExampleBottomSheetDialog bottomSheet = new ExampleBottomSheetDialog();
bottomSheet.show(getSupportFragmentManager(), "exampleBottomSheet");

// Image replacement
if (...) {
    ImageView img= (ImageView) findViewById(R.id.cafe);
    img.setImageResource(R.drawable.bar);
}

public class ExampleBottomSheetDialog extends BottomSheetDialogFragment {
private BottomSheetListener mListener;

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.bottom_sheet_layout, container, false);

    Button button1 = v.findViewById(R.id.button1);
    button1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            dismiss();
        }
    });

    return v;
}

public interface BottomSheetListener {
    void onButtonClicked(String text);
}

@Override
public void onAttach(Context context) {
    super.onAttach(context);

    try {
        mListener = (BottomSheetListener) context;
    } catch (ClassCastException e) {
        throw new ClassCastException(context.toString()
                + " must implement BottomSheetListener");
    }
}

Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
    ByteArrayOutputStream stream = new ByteArrayOutputStream();
    bmp.compress(Bitmap.CompressFormat.PNG, 100, stream);
    byte[] byteArray = stream.toByteArray();

Intent intent = new Intent(this, NextActivity.class);
intent.putExtra("picture", byteArray);
startActivity(intent);

Bundle extras = getIntent().getExtras();
byte[] byteArray = extras.getByteArray("picture");

Bitmap bmp = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);
ImageView image = (ImageView) findViewById(R.id.imageView1);

image.setImageBitmap(bmp);

Bundle args = new Bundle();
    if (...)
        args.putInt("drawable", R.drawable.bar);
    ExampleBottomSheetDialog bottomSheet = new ExampleBottomSheetDialog();
    bottomSheet.setArguments(args);
    bottomSheet.show(getSupportFragmentManager(), "exampleBottomSheet");

@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.bottom_sheet_layout, container, false);
    ...
    ImageView img = v.findViewById(R.id.cafe);
    int drawable = getArguments().getInt("drawable", R.drawable.default_drawable);
    img.setImageResource(drawable);
    ...
    return v;
}