FullScreenDialog.java

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
     super.onCreateView(inflater, container, savedInstanceState);
     View view = inflater.inflate(R.layout.layout_full_screen_dialog, container, false);

     Toolbar toolbar = view.findViewById(R.id.toolbar);
     toolbar.setNavigationIcon(R.drawable.ic_close_white_24dp);
     toolbar.setNavigationOnClickListener(view1 -> cancelUpload());
     toolbar.setTitle("My Dialog");

     return view;
}