android - 如何在没有身份验证的情况下使用来自表单的信息填充片段和火力库

Question

我对 Android Studio 和 Firebase 还很陌生，我想做的是在填写表单后单击按钮的同时在我的应用程序和 firebase 上填充一个片段。我不是在谈论身份认同。我的应用程序崩溃了。

这是表单所在的片段

public class Entreprisesfrag extends android.support.v4.app.Fragment {

    RecyclerView recyclerView;
    DatabaseReference dbref;
    FirebaseDatabase firebaseDatabase;

    public Entreprisesfrag() {
        // Required empty public constructor
    }
    @Override
    public void onCreate( Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setHasOptionsMenu(true);


    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        View view = inflater.inflate(R.layout.fragment_entreprises, container, false);

        recyclerView= view.findViewById(R.id.recv);

        recyclerView.setHasFixedSize(true);
        recyclerView.setLayoutManager (new LinearLayoutManager(getContext()));

        firebaseDatabase= FirebaseDatabase.getInstance();
        dbref= firebaseDatabase.getReference("Entreprises");


        return view;
    }

    @Override
    public void onStart() {
        super.onStart();
        FirebaseRecyclerAdapter<entreprises_class,ViewHolder>firebaseRecyclerAdapter= new FirebaseRecyclerAdapter<entreprises_class, ViewHolder>
                (entreprises_class.class,R.layout.entreprises_cardview, ViewHolder.class,dbref) {
            @Override
            protected void populateViewHolder(ViewHolder viewHolder, entreprises_class model, int position) {


            }
        };

        recyclerView.setAdapter(firebaseRecyclerAdapter);
    }



    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        super.onCreateOptionsMenu(menu, inflater);
        menu.clear();
        inflater.inflate(R.menu.recherche_activity_menu_item, menu);
        MenuItem item = menu.findItem(R.id.action_search);
        SearchView searchView = (SearchView) item.getActionView();
        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextSubmit(String query) {
                return false;
            }
            @Override
            public boolean onQueryTextChange(String newText) {
                //Do search code here
                return true;
            }
        });

    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {

        if (item.getItemId()==R.id.recherche)
        {

        }
        else if (item.getItemId()==R.id.filtrer)
        {

            Toast.makeText(getContext(), "Erreur de connexion ! Vérifiez l'adresse email utilisée et le mot de passe", Toast.LENGTH_SHORT).show();
        }
        return super.onOptionsItemSelected(item);
    }

}

Getter 和 Setter 类

public class entreprises_class {

    String nom, secteur, ville, image;

    public entreprises_class(){}

    public String getNom() {
        return nom;
    }

    public void setNom(String nom) {
        this.nom = nom;
    }

    public String getSecteur() {
        return secteur;
    }

    public void setSecteur(String secteur) {
        this.secteur = secteur;
    }

    public String getVille() {
        return ville;
    }

    public void setVille(String ville) {
        this.ville = ville;
    }

    public String getImage() {
        return image;
    }

    public void setImage(String image) {
        this.image = image;
    }



}

Firebase 类

public class Firebase_class {
    DatabaseReference dbref;
    Boolean aBoolean=null;
    ArrayList<entreprises_class> entreprises= new ArrayList<>();

    public Firebase_class(DatabaseReference dbref) {
        this.dbref=dbref;
    }

    public Boolean save(entreprises_class ent_class)
    {
        if(ent_class==null){
            aBoolean=false;
        }
        else
        {
            try
            {
                dbref.child("Entreprises").push().setValue(ent_class);
                aBoolean=true;

            }
            catch (DatabaseException databaseException)
            {
                databaseException.printStackTrace();
                aBoolean=false;
            }
        }
        return aBoolean;
    }

    public void fetchdata(DataSnapshot dataSnapshot)
    {
        entreprises.clear();

        for (DataSnapshot ds: dataSnapshot.getChildren())
        {
            entreprises_class ent_class= ds.getValue(entreprises_class.class);
            entreprises.add(ent_class);
        }
    }

    public ArrayList<entreprises_class> retrieve()
    {
        dbref.addChildEventListener(new ChildEventListener() {
            @Override
            public void onChildAdded(@NonNull DataSnapshot dataSnapshot, 
            @Nullable String s) {
                fetchdata(dataSnapshot);
            }

            @Override
            public void onChildChanged(@NonNull DataSnapshot dataSnapshot, 
            @Nullable String s) {
                fetchdata(dataSnapshot);

            }

            @Override
            public void onChildRemoved(@NonNull DataSnapshot dataSnapshot) {

            }

            @Override
            public void onChildMoved(@NonNull DataSnapshot dataSnapshot, 
            @Nullable String s) {

            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) {

            }
        });
        return entreprises;
    }
}

ViewHolder 类

public class ViewHolder extends RecyclerView.ViewHolder {

    TextView textView, textView1, textView2;
    ImageView imageView;

    public ViewHolder(View itemView) {
        super(itemView);

        textView= itemView.findViewById(R.id.entreprise_nom);
        textView1= itemView.findViewById(R.id.entreprise_secteur);
        textView2= itemView.findViewById(R.id.entreprise_sous_secteur);
        imageView=itemView.findViewById(R.id.entreprise_image);

    }

}

适配器类

public class Adapter extends RecyclerView.Adapter<ViewHolder>{
    Context cntx;
    ArrayList<entreprises_class> entreprises;

    public Adapter(Context cntx, ArrayList<entreprises_class> entreprises) {
        this.cntx = cntx;
        this.entreprises = entreprises;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view= LayoutInflater.from(cntx).inflate 
    (R.layout.entreprises_cardview, parent, false);
        return new ViewHolder(view);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {

        holder.textView.setText(entreprises.get(position).getNom());
        holder.textView1.setText(entreprises.get(position).getSecteur());
        holder.textView2.setText(entreprises.get(position).getVille());
        Picasso.get().load(entreprises.get(position) 
        .getImage()).into(holder.imageView);

    }

    @Override
    public int getItemCount() {
        return entreprises.size();
    }
}

标签： androidfirebase-realtime-databaseandroid-recyclerviewdata-retrieval