firestores

ReadData.java

private void readData(){
        CollectionReference collectionReference = firebaseFirestore.collection("data");
        collectionReference.get()
               .addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
                   @Override
                   public void onComplete(@NonNull Task<QuerySnapshot> task) {
                       progressDialog.dismiss();
                       if(task.getResult().isEmpty()){
                           Toast.makeText(MainActivity.this, "Data is empty", Toast.LENGTH_SHORT).show();
                       }else if(task.isSuccessful()){
                           WebsiteModel websiteModel = new WebsiteModel();
                           for(DocumentSnapshot documentSnapshot : task.getResult()){
                               websiteModel.setIdDocument(documentSnapshot.getId());
                               websiteModel.setName(documentSnapshot.get("name").toString());
                               websiteModel.setWebsite(documentSnapshot.get("website").toString());
                               websiteModel.setWebTopic(documentSnapshot.get("webTopic").toString());
                           }
                           modelWebsite.add(websiteModel);
                           showData();
                       }else{
                           Toast.makeText(MainActivity.this, "There is a problem", Toast.LENGTH_SHORT).show();
                       }
                   }
               }).addOnFailureListener(new OnFailureListener() {
            @Override
            public void onFailure(@NonNull Exception e) {
                progressDialog.dismiss();
                Toast.makeText(MainActivity.this, e.getMessage(), Toast.LENGTH_SHORT).show();
            }
        });
    }

    /**
     * I iterate the list because i just want to display in ArrayAdapter (String)
     */
    private void showData(){
        List<String> listDataString = new ArrayList<>();
        for (int i = 0; i < modelWebsite.size(); i++) {
            listDataString.add("IdDocument : "+modelWebsite.get(i).getIdDocument()+"\n"+
            "Name : " + modelWebsite.get(i).getName()+"\n"+
            "Website : " + modelWebsite.get(i).getWebsite()+"\n"+
            "webTopic : " + modelWebsite.get(i).getWebTopic());
        }
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, listDataString);
        listView.setAdapter(adapter);
    }