我正用我的回收视图面对这个问题。我正试着显示来自另一个firebase数据库的图像。它以前工作得很好，现在当我运行我的应用程序时，我得到两个空白的卡片视图和没有图像。我不确定这是怎么回事，因为它以前工作得很好。有人能帮我解决这个问题吗。提前谢谢你。下面是我的代码

//Code

 recyclerView = findViewById(R.id.recyclerView);
        RecyclerView.LayoutManager layoutManager = new GridLayoutManager(getApplicationContext(),1);

        recyclerView.setLayoutManager(layoutManager);
        myUploads = new ArrayList<Model>();
        aAdapter = new Adapter(MainActivity2.this, myUploads);
        recyclerView.setAdapter(aAdapter);
        aAdapter.notifyDataSetChanged();
        progressBar=findViewById(R.id.progressBar);



        databaseReference = FirebaseDatabase.getInstance("https://puttt0-4331.firebaseio.com").getReference("Images");


        databaseReference.addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot snapshot) {

                progressBar.setVisibility(View.GONE);

                if(snapshot.exists()){

                    for (DataSnapshot postsnapshot : snapshot.getChildren()) {

                        Model upload=postsnapshot.getValue(Model.class);
                        //myUploads.clear();

                        myUploads.add(upload);
                        aAdapter = new Adapter(MainActivity2.this, myUploads);
                        recyclerView.setAdapter(aAdapter);
                        //aAdapter.notifyDataSetChanged();
                        recyclerView.invalidate();


                    }







                    aAdapter.notifyDataSetChanged();