如何使用 Firebase 在 Android Studio 項目中將記錄的用戶數據作為用戶名檢索到導航標頭

Question

我是 Android 項目的新手。 我用 Firebase 創建項目。 在這個項目中，我想將記錄的用戶名添加到導航標題中的 textview。 我用於登錄或注冊模型選項。 但我不能。 有人對這個有經驗么？ 我的 firebase 數據庫數據顯示如下。

我想要這樣

我的家庭活動是這個

package com.cavad.firebaseproject;

import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;


public class Home extends AppCompatActivity
    implements NavigationView.OnNavigationItemSelectedListener {


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_home);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
            this, drawer, toolbar, R.string.navigation_drawer_open, 
 R.string.navigation_drawer_close);
    drawer.addDrawerListener(toggle);
    toggle.syncState();

    NavigationView navigationView = (NavigationView) 
 findViewById(R.id.nav_view);
    navigationView.setNavigationItemSelectedListener(this);

    Fragment category = new CategoryFragment();
    this.setDefaultFragment(category);
 }

 private void setDefaultFragment(Fragment defaultFragment)
 {
    this.replaceFragment(defaultFragment);
 }

 public void replaceFragment(Fragment destFragment)
 {
    FragmentManager fragmentManager = this.getSupportFragmentManager();
    FragmentTransaction fragmentTransaction = 
 fragmentManager.beginTransaction();
    fragmentTransaction.replace(R.id.category, destFragment);
    fragmentTransaction.commit();
 }

@Override
public void onBackPressed() {
    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    if (drawer.isDrawerOpen(GravityCompat.START)) {
        drawer.closeDrawer(GravityCompat.START);
    } else {
        super.onBackPressed();
    }
}

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

  @Override
  public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}

@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
    // Handle navigation view item clicks here.
    int id = item.getItemId();

    if (id == R.id.nav_camera) {
        // Handle the camera action
    } else if (id == R.id.nav_gallery) {

    } else if (id == R.id.nav_slideshow) {

    } else if (id == R.id.nav_manage) {

    } else if (id == R.id.nav_share) {

    } else if (id == R.id.nav_send) {

    }

    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    drawer.closeDrawer(GravityCompat.START);
    return true;
  }
 }

我的 nav_header xml 文件是這個 nav_header_home.xml //

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/colorPrimaryDark"
android:gravity="bottom"
android:orientation="vertical"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
android:theme="@style/ThemeOverlay.AppCompat.Dark">

<TextView
    android:id="@+id/userName"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:gravity="center"
    android:text="userName"
    android:textColor="@color/white"
    android:textSize="20sp"
    android:layout_marginTop="15dp"
    android:layout_marginBottom="10dp"
    android:textStyle="bold"/>

</LinearLayout>   

我的模型類是這個

 package com.cavad.firebaseproject.Model;

public class User {

private String userName;
private String password;
private String email;

public User(){
}

public User(String userName, String password, String email) {
    this.userName = userName;
    this.password = password;
    this.email = email;
}

public String getUserName() {
    return userName;
}

public void setUserName(String userName) {
    this.userName = userName;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public String getEmail() {
    return email;
}

public void setEmail(String email) {
    this.email = email;
}
}

我的 Firebase 數據庫規則是這樣的

  {
    "rules": {
    ".read": true,
    ".write": true
    }
   }

我的登錄活動是這樣的

 package com.cavad.firebaseproject;

 import android.content.Intent;
 import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.support.v4.app.Fragment;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.EditText;
 import android.widget.ImageView;
 import android.widget.Toast;

 import com.cavad.firebaseproject.Model.User;
 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;
public class Login extends Fragment {

EditText user, password;
ImageView signin;

FirebaseDatabase database;
DatabaseReference users;

public Login() {

}

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

    database = FirebaseDatabase.getInstance();
    users = database.getReference("Users");

    user = view.findViewById(R.id.name);
    password = view.findViewById(R.id.password);
    signin = view.findViewById(R.id.submit);

    signin.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v){

  signin(user.getText().toString(),password.getText().toString());
        }
    });

    return view;
   }
  private void signin(final String user, final String pwd){
    users.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
            if (dataSnapshot.child(user).exists())
            {
                if (!user.isEmpty())
                {
                    User login = 
  dataSnapshot.child(user).getValue(User.class);
                    if (login.getPassword().equals(pwd))
                    {
                        Toast.makeText(getActivity(), "Uğurla daxil 
 oldunuz", Toast.LENGTH_SHORT).show();
                        startActivity(new 
 Intent(getActivity().getApplication(), Home.class));

                    }
                    else
                        Toast.makeText(getActivity(), "Zəhmət olmasa 
 Şifrəni düzgün daxil edin", Toast.LENGTH_SHORT).show();
                }
                else
                {
                    Toast.makeText(getActivity(), "Zəhmət olmasa 
 İstifadəçi adınızı daxil edin", Toast.LENGTH_SHORT).show();
                }
            }
            else
                Toast.makeText(getActivity(), "Belə bir istifadəçi adı 
   tapılmadı !!!", Toast.LENGTH_SHORT).show();
        }

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

        }
    });
  }
 }

我的登錄活動 xml 是這個

 <LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:context=".Login"
android:background="@color/colorPrimaryDark"
android:orientation="vertical">

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:weightSum="2"
    android:layout_marginTop="7dp"
    android:layout_marginBottom="7dp">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <android.support.design.widget.TextInputLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="7dp"
            android:layout_marginBottom="7dp"
            app:hintEnabled="false"
            android:layout_marginLeft="20dp"
            android:layout_marginRight="20dp">

            <EditText
                android:id="@+id/name"
                android:layout_width="match_parent"
                android:layout_height="48dp"
                android:hint="@string/name"
                android:inputType="text"
                android:textSize="20sp"
                android:drawableStart="@drawable/ic_user"
                android:drawableLeft="@drawable/ic_user"
                android:drawablePadding="10dp"
                android:background="@drawable/edttext_background"
                android:paddingRight="10dp"
                android:paddingLeft="10dp"/>
        </android.support.design.widget.TextInputLayout>

        <android.support.design.widget.TextInputLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="7dp"
            android:layout_marginBottom="7dp"
            app:hintEnabled="false"
            app:passwordToggleDrawable="@drawable/visibility"
            app:passwordToggleEnabled="true"
            android:layout_marginLeft="20dp"
            android:layout_marginRight="20dp">

            <EditText
                android:id="@+id/password"
                android:layout_width="match_parent"
                android:layout_height="48dp"
                android:textSize="20sp"
                android:inputType="textPassword"
                android:hint="@string/password"
                android:drawableStart="@drawable/ic_lock"
                android:drawableLeft="@drawable/ic_lock"
                android:background="@drawable/edttext_background"
                android:drawablePadding="10dp"
                android:paddingRight="10dp"
                android:paddingLeft="10dp" />
        </android.support.design.widget.TextInputLayout>

        <ImageView
            android:id="@+id/submit"
            android:layout_width="48dp"
            android:layout_height="48dp"
            android:gravity="center"
            android:layout_gravity="center"
            android:src="@drawable/ic_check"
            android:background="@drawable/check_background"
            android:layout_marginTop="15dp"
            android:layout_marginBottom="15dp"/>

    </LinearLayout>

</LinearLayout>

</LinearLayout>

Answer 1

步驟1.獲取當前登錄的用戶： -

獲取當前用戶的推薦方法是調用getCurrentUser方法。 如果沒有用戶登錄，則getCurrentUser返回null。示例： -

FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
if (user != null) {
// Name, email address, and profile photo Url
String name = user.getDisplayName();
String email = user.getEmail();
Uri photoUrl = user.getPhotoUrl();

// Check if user's email is verified
boolean emailVerified = user.isEmailVerified();

// The user's ID, unique to the Firebase project. Do NOT use this value to
// authenticate with your backend server, if you have one. Use
// FirebaseUser.getIdToken() instead.
String uid = user.getUid();
}

如需更多，請查看鏈接

管理Firebase中的用戶

步驟2. 將其設置為導航視圖標題： -您可以獲得如下文本視圖 ： -

NavigationView navigationView = (NavigationView) findViewById(R.id.your_nav_view_id);
View header = navigationView.getHeaderView(0)
TextView text = (TextView) header.findViewById(R.id.textView);

Answer 2

如果您想檢索存儲在實時數據庫中的登錄用戶電子郵件、用戶名和圖片，並將它們顯示在導航標題中，那么您只需按照以下步驟操作：

    NavigationView navigationView = findViewById(R.id.nav_view);
        database = FirebaseDatabase.getInstance();
        auth = FirebaseAuth.getInstance();

    database.getReference().child("Users").child(auth.getUid())
            .addListenerForSingleValueEvent(new ValueEventListener() {
                @Override
                public void onDataChange(@NonNull DataSnapshot snapshot) {
                //we have Users class which contain user properties and methods.
                    User user = snapshot.getValue(User.class);

                    View header = navigationView.getHeaderView(0);
                    nav_email = header.findViewById(R.id.nav_email);
                    nav_username = header.findViewById(R.id.nav_username);
                    nav_profile = header.findViewById(R.id.nav_profilePic);

            Picasso.get().load(user.getProfilePic()).placeholder(R.drawable.avatar).into(nav_profile);
                    nav_email.setText(user.getMail());
                    nav_username.setText(user.getUserName());
                }

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

                }
            });

如果您想使用 Picasso 從實時數據庫中檢索圖像，然后將其設置在導航標題 imageview 上，則在您的包 Gradle 模塊文件中添加以下依賴項：

    implementation 'com.squareup.picasso:picasso:2.71828'

然后你可以在你的項目中使用畢加索。

Answer 3

在導航標題中從 firebase 實時數據庫中檢索記錄的用戶數據

// xml文件

    <TextView
        android:id="@+id/your_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:fontFamily="@font/gotham_bold"
        android:text="User Name"
        android:textColor="@color/brown"
        android:textSize="18sp"
     />

        <TextView
            android:id="@+id/user_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:fontFamily="@font/gotham_book"
            android:text="User Name"
            android:textColor="@color/brown"
           android:textSize="15sp"
            android:layout_gravity="center"
            />

// 代碼

    firebaseDatabase.getReference().child("Users").child(auth.getUid())
            .addListenerForSingleValueEvent(new ValueEventListener() {
                @Override
                public void onDataChange(@NonNull DataSnapshot snapshot) {
                   
                    User user = snapshot.getValue(User.class);

                    View header = navigationView.getHeaderView(0);

                    name = header.findViewById(R.id.your_name);
                    username = header.findViewById(R.id.user_name);

                    name.setText(user.getName1());
                    username.setText("@" + user.getUsername1());
                }

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

                }
            });