How to make auto refreshing on recyclerview Android while getting data from firebase firestore-CodePudding

I added a swipe SwipeRefreshLayout but the data only show when I swipe down to refresh. If I don't refresh the data didn't show. I want an auto refresh on the background when an activity is created.

This is my XML

<androidx.swiperefreshlayout.widget.SwipeRefreshLayout
        android:id="@ id/swipeRefreshLayout"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <androidx.recyclerview.widget.RecyclerView
            android:id="@ id/rcv_inventoryCars"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:layout_marginTop="8dp"
            app:layout_constraintBottom_toBottomOf="parent"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintHorizontal_bias="0.0"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="parent" />

    </androidx.swiperefreshlayout.widget.SwipeRefreshLayout>

After getting data from the firebase I added it to the list and add that list into the adapter. I try the adding to adapter thing inside the onCompleteListener but the app crashed.

This is my Java code

binding.swipeRefreshLayout.setOnRefreshListener(() -> {
            adapter.notifyDataSetChanged();
            binding.swipeRefreshLayout.setRefreshing(false);
        });
firestore.collection("Inventory").document(auth.getCurrentUser().getUid())
                    .collection("CarDetails")
                    .get().addOnCompleteListener(task -> {
                        if (task.isSuccessful()){
                            for(DocumentSnapshot documentSnapshot : task.getResult()){
                                carID = documentSnapshot.getString("carID");
                                title = documentSnapshot.getString("title");
                                makeYear = documentSnapshot.getString("makeYear");
                                fuel = documentSnapshot.getString("fuel");
                                condition = documentSnapshot.getString("condition");
                                date = documentSnapshot.getString("date");
                                kmDriven = documentSnapshot.getString("kmDriven");
                                image = documentSnapshot.getString("imageLink");
                                InventoryListModel model = new InventoryListModel(carID, title, makeYear, fuel, condition, date, image, kmDriven);
                                carList.add(model);
                            }
                        } else {
                            Toast.makeText(this, "Something went wrong", Toast.LENGTH_SHORT).show();
                        }
                    });


adapter = new InventoryCarListAdapter(this, carList);
binding.rcvInventoryCars.setAdapter(adapter);
adapter.notifyDataSetChanged();

CodePudding user response：

When you're calling Query#get() it means that you're reading the database precisely once. If you want to listen for real-time updates, then you should use a real-time listener. Here are the docs:

https://firebase.google.com/docs/firestore/query-data/listen

But in this case, I cannot see any reasons why you would use a SwipeRefreshLayout, because there is no need for any swipe since you're always getting real-time updates.