按 T​​imeStamp 升序排列 Firestore 数据

I am storing Ideas posted by the application in Firestore. The data is stored in Firestore like this Ideas/{documentID}/IdeaObject. The issue is when I retrieve the data it is not sorted w.r.t time it was posted. The ideas that are retrieved are in according to the id's of their documentID which is automatically create by Firestore. I have used ServerTimestamp in my Model Class and also when I retrieve it, I use the orderBy method with my Firestore reference but still nothing.

Idea.java

public class Idea {
    @ServerTimestamp
    private Date date;
    private String title, idea, timeCommitment, ideaStage, postedBy, website, videoPitch;
    private int views, favorites;
    private ArrayList<String> lookingFor = new ArrayList<>();
    private ArrayList<String> tags = new ArrayList<>();
    private String userID;
    private String timeStamp;

    public Idea() {
    }

    public Idea(String title, String idea, String timeCommitment, String ideaStage, String postedBy, String website, String videoPitch, int views, int favorites, ArrayList<String> lookingFor, ArrayList<String> tags, String userID, String timeStamp) {
        this.title = title;
        this.idea = idea;
        this.timeCommitment = timeCommitment;
        this.ideaStage = ideaStage;
        this.postedBy = postedBy;
        this.website = website;
        this.videoPitch = videoPitch;
        this.views = views;
        this.favorites = favorites;
        this.lookingFor = lookingFor;
        this.tags = tags;
        this.userID = userID;
        this.timeStamp = timeStamp;
    }

创意发布方式

  private void postIdea() {

        final String ideaID = UUID.randomUUID().toString();
        final SimpleDateFormat sdf = new SimpleDateFormat("yyyy.MM.dd.HH.mm.ss");
        Timestamp timestamp = new Timestamp(System.currentTimeMillis());


        Idea ideas = new Idea(title, idea, timeCommitment, ideaStage, AppValues.fullName, website, videoPitch, 0, 0, lookingFor, tags, AppValues.userId, "" + timestamp.getTime());

        firestoreDb.collection("ideas")
                .document(ideaID)
                .set(ideas)
                .addOnSuccessListener(new OnSuccessListener<Void>() {
                    @Override
                    public void onSuccess(Void aVoid) {
                        postIdeaUser(ideaID);
                    }
                })
                .addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        hideLoadingDialog();
                        showToast(e.getMessage());
                    }
                });
    }

按时间检索所有创意

   firestoreDb.collection("ideas")
                .orderBy("timeStamp", Query.Direction.ASCENDING)
                .get()
                .addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
                    @Override
                    public void onComplete(@NonNull Task<QuerySnapshot> task) {
                        if (task.isSuccessful()) {

                            ideaArrayList = new ArrayList<>();
                            ideaArrayList.clear();

                            for (DocumentSnapshot documentSnapshot : task.getResult()) {
                                Idea idea = documentSnapshot.toObject(Idea.class);
                                if (!idea.getUserID().equals(AppValues.userId)) {
                                    ideaArrayList.add(idea);
                                }
                            }

                            callAdapter();

                        } else {
                            Log.d(TAG, "Error getting documents: ", task.getException());
                            progressBar.setVisibility(View.GONE);
                            swipeRefresh.setEnabled(true);
                            errorText.setVisibility(View.VISIBLE);
                        }
                    }
                }); 

我想要实现的是检索所有想法并让它们按 TimeStamp 值升序排列.

firestoreDb.collection("ideas")
            .orderBy("timeStamp", Query.Direction.ASCENDING)

firestoreDb.collection("ideas")
            .orderBy("date", Query.Direction.ASCENDING)