为什么在尝试更新子值时，会在我的数据库下创建一个新的子项？

Question

我正在尝试更新Firebase数据库中的quantity子值，每当尝试更新时，都会创建一个新的子值，而不是更新当前值。如屏幕截图所示，当它应该更新当前数量时，将生成一个数量为2的新UID。我不知道为什么会发生这种情况，有人能帮我吗。我附上了一张数据库结构的图片，

loggedInUID: U4Rc9hD6WHUC5vjqCezclsqKdcr2
tappedonimagetimestamp: U4Rc9hD6WHUC5vjqCezclsqKdcr2 00:20:44

  @Override
public void onBindViewHolder(@NonNull ViewHolder holder, @SuppressLint("RecyclerView") final int position) {
    holder.produceName.setText(cartArrayList.get(position).getProductName());
    Log.i("productname", cartArrayList.get(position).getProductName());

    holder.producePrice.setText("$" + cartArrayList.get(position).getItemPrice());
    holder.plusImageView.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View view) {
            Log.i("produtUID", cartArrayList.get(position).getTimestamp());

            getCurrentUserUid();


            count = count + 1;
            holder.middleQUanityTv.setText(count + "");

            Log.i("tappedonimagetimestamp", cartArrayList.get(position).getTimestamp());
            Log.i("loggedInUID", loggedInUserId);


            FirebaseDatabase.getInstance().getReference("Cart").child(loggedInUserId).child(cartArrayList.get(position).getTimestamp()).child("quantity").setValue(count);


        }
    });


    //Log.i("IMAGES", productArrayList.get(position).getProductImage());
    Glide.with(ct)
            .load(cartArrayList.get(position).getProductImage())
            .centerCrop()
            .into(holder.productImage);


}


public void addItemToCart(){

    SimpleDateFormat formatter = new SimpleDateFormat(" HH:mm:ss ");
    Date date = new Date(System.currentTimeMillis());
    timeStamp = loggedInUserId + formatter.format(date);



    userDictionary.put("itemPrice", selectedPrice.trim());
    userDictionary.put("productname",productNameText.trim());
    userDictionary.put("description", selectedStringProductDescrtipon.trim());
    userDictionary.put("uid",loggedInUserId.trim());
    userDictionary.put("productImage", selectedImage.trim());
    userDictionary.put("datee",date.toString());
    userDictionary.put("name",loggedInUserName.trim());
    userDictionary.put("timestamp",timeStamp.trim());
    userDictionary.put("time",formatter.format(date).trim());
    userDictionary.put("quantity","1");



    uploadPostRef.child("Cart").child(loggedInUserId).child(timeStamp).setValue(userDictionary).addOnSuccessListener(new OnSuccessListener<Void>() {
        @Override
        public void onSuccess(Void unused) {
            Log.i("sucessfully added","sucesssfully added to cart..");
            getLoggedInUserData();

        }
    });
    numberInCartIv.setVisibility(View.VISIBLE);


}

Answer 1

所以问题是，当我向购物车添加商品时，我在每个值的末尾都使用了trim方法。我只是删除了这个，然后运行我的代码，一切正常。