从Firestore加载文档时如何使用进度条

Question

我正在尝试从Firestore中检索文档。加载文档时如何添加进度条？ 这是我的代码：

documentreference.addSnapshotListener(new EventListener<DocumentSnapshot>() {
                        @Override
                        public void onEvent(@Nullable DocumentSnapshot documentSnapshot, @Nullable FirebaseFirestoreException e) {
                            String UserId=documentSnapshot.getId();

                            ProductModel productModel1 = documentSnapshot.toObject(ProductModel.class).withId(UserId);
                            productModels.add(productModel1);
                            chatListAdapter.notifyDataSetChanged();




                        }
                    });

Answer 1

在活动开始时显示ProgressBar，即只需在xml中定义一个ProgressBar，并确保其在开始时可见。

现在，当所有数据加载完毕后，只需将其删除即可。

documentreference.addSnapshotListener(new EventListener < DocumentSnapshot > () {
  @Override
  public void onEvent(@Nullable DocumentSnapshot documentSnapshot, @Nullable FirebaseFirestoreException e) {
    String UserId = documentSnapshot.getId();

    ProductModel productModel1 = documentSnapshot.toObject(ProductModel.class).withId(UserId);
    productModels.add(productModel1);
    chatListAdapter.notifyDataSetChanged();
    progressBar.setVisibilty(View.GONE);
  }
});

Answer 2

documentreference.addSnapshotListener(new EventListener < DocumentSnapshot > () {
  @Override
  public void onEvent(@Nullable DocumentSnapshot documentSnapshot, @Nullable FirebaseFirestoreException e) {
    String UserId = documentSnapshot.getId();

    ProductModel productModel1 = documentSnapshot.toObject(ProductModel.class).withId(UserId);
    productModels.add(productModel1);
    chatListAdapter.notifyDataSetChanged();
    progressBar.setVisibilty(View.GONE);
  }
});