![](/img/trans.png)
[英]I cant get my constructors from my subclasses to read the Strings I have put in them
[英]I cant get the values from Firebase and put them in to TextView in fragment
在我的應用程序中,我創建了登錄和注冊頁面,並將用戶名和電子郵件保存到我的Firebase數據庫中。 我還用片段進行了底部導航。 我想從Firebase中獲取這些值(名稱,郵件),並將其放入配置文件片段的TextView中。 當我嘗試此操作時,我的應用程序崩潰了。 我怎么解決這個問題?
public class ProfileFragment extends Fragment {
private FirebaseDatabase mFirebaseDatabase;
private FirebaseAuth mAuth;
private String userID;
private TextView tName;
private TextView tEmail;
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View profileView = inflater.inflate(R.layout.fragment_profile, null);
tName=profileView.findViewById(R.id.tv_name);
tEmail=profileView.findViewById(R.id.tv_email);
mAuth=FirebaseAuth.getInstance();
mFirebaseDatabase=FirebaseDatabase.getInstance();
final DatabaseReference myRef=mFirebaseDatabase.getReference("users");
FirebaseUser user=mAuth.getCurrentUser();
userID=user.getUid();
myRef.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot ds: dataSnapshot.getChildren()){
User user=new User();
user.setUserName(ds.child(userID).getValue(User.class).getUserName());
user.setUserEmail(ds.child(userID).getValue(User.class).getUserEmail());
tName.setText(user.getUserName());
tEmail.setText(user.getUserEmail());
}
}
@Override
public void onCancelled(DatabaseError databaseError) {}
});
return profileView;
}
}
在xml文件夾中創建文件
<?xml version="1.0" encoding="utf-8"?>
<defaultsMap>
<entry>
<key>email</key>
<value>name</value>
</entry>
public FirebaseRemoteConfig getmFirebaseRemoteConfig() {
mFirebaseRemoteConfig = FirebaseRemoteConfig.getInstance();
FirebaseRemoteConfigSettings configSettings = new FirebaseRemoteConfigSettings.Builder()
//.setDeveloperModeEnabled(BuildConfig.DEBUG)
.setDeveloperModeEnabled(false)
.build();
mFirebaseRemoteConfig.setConfigSettings(configSettings);
mFirebaseRemoteConfig.setDefaults(R.xml.remote_config_defaults);
return mFirebaseRemoteConfig;
}
假設您的數據庫結構與此類似:
Firebase-root
|
--- users
|
--- uid
|
--- name: "John"
|
--- email: "john@email.com"
要打印姓名和電子郵件,請使用以下代碼和模型類:
String uid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference uidRef = rootRef.child("users").child(uid);
ValueEventListener valueEventListener = new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
User user = dataSnapshot.getValue(User.class);
String name = user.getUserName();
tName.setText(name);
String email = user.getUserEmail();
tEmail.setText(email);
Log.d("TAG", name + " / " + email);
}
@Override
public void onCancelled(DatabaseError databaseError) {}
};
uidRef.addListenerForSingleValueEvent(valueEventListener);
如果要使用String類將它們打印得更簡單,請使用以下代碼:
String uid = FirebaseAuth.getInstance().getCurrentUser().getUid();
DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
DatabaseReference usersRef = rootRef.child("users").child(uid);
ValueEventListener valueEventListener = new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
String name = dataSnapshot.child("name").getValue(String.class);
tName.setText(name);
String email = dataSnapshot.child("email").getValue(String.class);
tEmail.setText(email);
Log.d("TAG", name + " / " + email);
}
@Override
public void onCancelled(DatabaseError databaseError) {}
};
uidRef.addListenerForSingleValueEvent(valueEventListener);
在這兩種情況下,輸出均為: John / john@email.com
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.