How to search list of data from firebase firestore using android searchView

Question

I'm using the Cloud Firestore of Firebase to store users and the android Searchview to provide search fonctionnality. When a user search for "jonathan" for example, if he begin typing "j" i want to bring in all users with the name starting par "j". How can i achieve this ?

Here is what i have tried:

@Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);

        MenuItem search = menu.findItem(R.id.action_search);
        SearchView searchView = (SearchView) search.getActionView();

        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {

            @Override
            public boolean onQueryTextSubmit(String query) {
                //Toast.makeText(MainActivity.this, "SEARCH " + query, Toast.LENGTH_LONG).show();
                searchUsers(query);
                return false;
            }

            @Override
            public boolean onQueryTextChange(String newText) {
                //Toast.makeText(MainActivity.this, "SEARCH " + newText, Toast.LENGTH_LONG).show();
                searchUsers(newText);
                return false;
            }
        });

        return true;
    }

Getting the user from Firebase:

private void searchUsers(String recherche) {
    if(recherche.length() > 0)
    recherche = recherche.substring(0,1).toUpperCase() + recherche.substring(1).toLowerCase();
    listUsers = new ArrayList<>();

    db.collection("users").whereGreaterThanOrEqualTo("name", recherche)
            .addSnapshotListener(new EventListener<QuerySnapshot>() {
                @Override
                public void onEvent(@Nullable QuerySnapshot snapshots,
                                    @Nullable FirebaseFirestoreException e) {
                    if (e != null) {
                        System.err.println("Listen failed:" + e);
                        return;
                    }
                    listUsers = new ArrayList<User>();

                    for (DocumentSnapshot doc : snapshots) {
                        User user = doc.toObject(User.class);
                        listUsers.add(user);
                    }
                    updateListUsers(listUsers);
                }
            });
}

This works only for the first letter "j" as soon as i add "ja" for example i still have all the "jonathan" displayed

Answer 1

Thanks to the suggestion of @Oby if found the solution. In fact i dont really need to query the database every time the search is triggered since i have the list of users. I just have to make the search on the list like this: We get the list first:

private void getUsers() {
        db.collection("users").whereEqualTo("etat", 1)
                .addSnapshotListener(new EventListener<QuerySnapshot>() {
                    @Override
                    public void onEvent(@Nullable QuerySnapshot snapshots,
                                        @Nullable FirebaseFirestoreException e) {
                        if (e != null) {
                            System.err.println("Listen failed:" + e);
                            return;
                        }
                        listUsers = new ArrayList<User>();

                        for (DocumentSnapshot doc : snapshots) {
                            User user = doc.toObject(User.class);
                            listUsers.add(user);
                        }
                        updateListUsers(listUsers);
                    }
                });
    }

Here is the search function:

private void searchUsers(String recherche) {
        if (recherche.length() > 0)
            recherche = recherche.substring(0, 1).toUpperCase() + recherche.substring(1).toLowerCase();

        ArrayList<User> results = new ArrayList<>();
        for(User user : listUsers){
            if(user.getName() != null && user.getName().contains(recherche)){
                results.add(user);
            }
        }
        updateListUsers(results);
    }

Here i notify the the Adapter of the RecyclerView that the data changed:

private void updateListUsers(ArrayList<User> listUsers) {

        // Sort the list by date
        Collections.sort(listUsers, new Comparator<User>() {
            @Override
            public int compare(User o1, User o2) {
                int res = -1;
                if (o1.getDate() > (o2.getDate())) {
                    res = 1;
                }
                return res;
            }
        });

        userRecyclerAdapter = new UserRecyclerAdapter(listUsers, InvitationActivity.this, this);
        rvUsers.setNestedScrollingEnabled(false);
        rvUsers.setAdapter(userRecyclerAdapter);
        layoutManagerUser = new LinearLayoutManager(getApplicationContext());
        rvUsers.setLayoutManager(layoutManagerUser);
        userRecyclerAdapter.notifyDataSetChanged();
    }

And of course the SearchView:

 @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);

        MenuItem search = menu.findItem(R.id.action_search);
        SearchView searchView = (SearchView) search.getActionView();

        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {

            @Override
            public boolean onQueryTextSubmit(String query) {
                //Toast.makeText(MainActivity.this, "SEARCH " + query, Toast.LENGTH_LONG).show();
                searchUsers(query);
                return false;
            }

            @Override
            public boolean onQueryTextChange(String newText) {
                //Toast.makeText(MainActivity.this, "SEARCH " + newText, Toast.LENGTH_LONG).show();
                searchUsers(newText);
                return false;
            }
        });

        return true;
    }

Answer 2

My way of searching is rather inefficient as I am using two recyclerviews, one is hidden and the other with the data visible. All data in the document is fetched to an array and I query the array in real-time as you want. The data remains synced always so it seems real-time. Not a good practice but it gets the job done for me. If you need further help I can create a gist for you in that.

The proper way would be to use this official link to search for exactly what you need Full-text search