java - 从 firebase 在导航栏中加载个人资料图片和用户名

Question

数据库结构图

数据库结构代码

我正在尝试在导航标题中检索用户在注册过程中保存的个人资料图像和用户名。这是我做的事情。起初我试图获取字符串当前用户 ，但它向我显示空指针异常，然后我尝试使用 if 语句并将子级从当前用户 id更改为Users，它只解决了空指针，但这并没有从 firebase 检索数据。

MainActivity.java

   import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import com.squareup.picasso.Picasso;

import de.hdodenhof.circleimageview.CircleImageView;

public class MainActivity extends AppCompatActivity {
    private NavigationView navigationView;
    private DrawerLayout drawerLayout;
    private RecyclerView postlist;
    private Toolbar mToolbar;
    private ActionBarDrawerToggle actionBarDrawerToggle;
    private FirebaseAuth mAuth;
    private FirebaseUser FirebaseUser;
    private DatabaseReference  UsersRef;
    private CircleImageView NavProfileImage;
    private TextView NavProfileUserName;
    String currentUserID;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        FirebaseUser mFirebaseUser = mAuth.getCurrentUser();
        if (mFirebaseUser != null) {
            currentUserID = mFirebaseUser.getUid();
        }
        mAuth = FirebaseAuth.getInstance();



        mToolbar =(Toolbar) findViewById(R.id.main_page_toolbar);
        setSupportActionBar(mToolbar);
        getSupportActionBar().setTitle("Home");

        drawerLayout = (DrawerLayout) findViewById(R.id.drawable_layout);
       actionBarDrawerToggle =  new ActionBarDrawerToggle(MainActivity.this,drawerLayout,R.string.drawer_open, R.string.drawer_close);
        navigationView = (NavigationView)findViewById(R.id.navigation_view);
       drawerLayout.addDrawerListener(actionBarDrawerToggle);
       actionBarDrawerToggle.syncState();
       getSupportActionBar().setDisplayHomeAsUpEnabled(true);


        View navView = navigationView.inflateHeaderView(R.layout.nav_header);
        NavProfileImage = (CircleImageView)navView.findViewById(R.id.nav_profile_image);
        NavProfileUserName = (TextView) navView.findViewById(R.id.nav_user_full_name);

        UsersRef = FirebaseDatabase.getInstance().getReference().child("Users");
        UsersRef.child(currentUserID).addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot)
            {
                if(dataSnapshot.exists())
                {   if (dataSnapshot.hasChild("fullname")){
                    String fullname = dataSnapshot.child("fullname").getValue().toString();
                    NavProfileUserName.setText(fullname);
                }if (dataSnapshot.hasChild("profileimages")) {
                    String image = dataSnapshot.child("profileimages").getValue().toString();
                    Picasso.with(MainActivity.this).load(image).placeholder(R.drawable.profile).into(NavProfileImage);

                }else {
                    Toast.makeText(MainActivity.this, "Profile name do not exists...", Toast.LENGTH_SHORT).show();
                }




                }
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {

            }
        });

        navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item)
            { UserMenuSelector(item);

                return false;
            }
        });
    }

    @Override
    protected void onStart() {
        super.onStart();
        FirebaseUser currentUser = mAuth.getCurrentUser();
        if (currentUser == null)
        {
            sendUserToLoginActivity();
        }else{
            CheckUserExistance();
        }
    }

    private void CheckUserExistance()
    {
        final String current_user_id = mAuth.getCurrentUser().getUid();
          UsersRef.addValueEventListener(new ValueEventListener() {
              @Override
              public void onDataChange(DataSnapshot dataSnapshot) {
                  if (!dataSnapshot.hasChild(current_user_id)){
                      sendUserToSetupActivity();
                  }
              }

              @Override
              public void onCancelled(DatabaseError databaseError) {

              }
          });
    }

    private void sendUserToSetupActivity() {
        Intent setupIntent = new Intent(MainActivity.this, SetupActivity.class);
        setupIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
        startActivity(setupIntent);
        finish();

    }

    private void sendUserToLoginActivity()
    {
        Intent loginIntent = new Intent(MainActivity.this, LoginActivity.class);
         loginIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
         startActivity(loginIntent);
         finish();

    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if (actionBarDrawerToggle.onOptionsItemSelected(item))
        {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    private void UserMenuSelector(MenuItem item)
    {
        switch (item.getItemId())
        {
            case R.id.nav_home:
                Toast.makeText(this,"Home",Toast.LENGTH_SHORT).show();
                break;
            case R.id.nav_post:
                break;
            case R.id.nav_Profile:
                Toast.makeText(this,"profile",Toast.LENGTH_SHORT).show();
                break;
            case R.id.nav_find_friends:
                Toast.makeText(this,"frns",Toast.LENGTH_SHORT).show();
                break;
            case R.id.nav_logout:
                mAuth.signOut();
                sendUserToLoginActivity();
                break;
        }
    }
}

标签： javaandroidfirebasefirebase-realtime-database

Answer 1

我使用滑行从 firebase 加载图像。它会是这样的：

import com.bumptech.glide.Glide;

UserModel userModel = new UserModel;

Glide.with(YourActivity.this)
  .load(userModel.getUser_image())
  .into(user_image);

有关更多信息，请查看github 存储库。