Setter和Getter返回null以从Facebook登录获取姓名，电子邮件，个人资料照片和身份证

Question

所以我打算将登录facebook的信息存储到getter和setter，以便我可以发布它可以从BroadcastFragment.java发布到我的Firebase数据库中。我不明白为什么它总是返回null。我在FacebookLogin.java中放置我的二传手的错误是什么？我的User.java有问题吗？

FacebookLogin.java

public class FacebookLogin extends AppCompatActivity{
private static final String TAG = "FacebookLogin";

private LoginButton loginButton;
private CallbackManager callbackManager;
private FirebaseAuth firebaseAuth;
private FirebaseAuth.AuthStateListener firebaseAuthListener;
public DatabaseReference mRootRef;
public Firebase mRef;
private ProgressBar progressBar;

private final String uid = getUid();

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    FacebookSdk.sdkInitialize(getApplicationContext());
    setContentView(R.layout.facebook_login);
    Firebase.setAndroidContext(this);

    mRootRef = FirebaseDatabase.getInstance().getReference();
    mRef = new Firebase("https://peoplehelper-c5a97.firebaseio.com/users");

    progressBar = (ProgressBar) findViewById(R.id.progressBar);

    callbackManager = CallbackManager.Factory.create();
    loginButton = (LoginButton) findViewById(R.id.loginButton);
    loginButton.setReadPermissions(Arrays.asList("email", "public_profile"));
    loginButton.registerCallback(callbackManager, new FacebookCallback<LoginResult>()
    {
        @Override
        public void onSuccess(LoginResult loginResult)
        {
            Log.d("", "facebook:onSuccess:" + loginResult);
            handleFacebookAccessToken(loginResult.getAccessToken());
        }

        @Override
        public void onCancel()
        {Toast.LENGTH_SHORT).show();
            Log.d(TAG, "facebook:onCancel");
        }

        @Override
        public void onError(FacebookException error)
        {
            //Toast.makeText(getApplicationContext(), "Error", Toast.LENGTH_SHORT).show();
            Log.d(TAG, "facebook:onError", error);
        }
    });

    firebaseAuth = FirebaseAuth.getInstance();
    firebaseAuthListener = new FirebaseAuth.AuthStateListener()
    {
        @Override
        public void onAuthStateChanged(@NotNull FirebaseAuth firebaseAuth)
        {
            FirebaseUser user = firebaseAuth.getCurrentUser();
            if (user != null)
            {
                Log.d(TAG, "onAuthStateChanged:signed_in:" + user.getUid());
            }
            else
            {
                Log.d(TAG, "onAuthStateChanged:signed_out");
            }
        }
    };

}

private void handleFacebookAccessToken(AccessToken accessToken)
{
    Log.d(TAG, "handleFacebookAccessToken:" + accessToken);

    progressBar.setVisibility(View.VISIBLE);
    loginButton.setVisibility(View.GONE);
    final FirebaseUser users = FirebaseAuth.getInstance().getCurrentUser();

    /**String uid = users.getUid();*/

    AuthCredential credential = FacebookAuthProvider.getCredential(accessToken.getToken());
    firebaseAuth.signInWithCredential(credential).addOnCompleteListener(this, new OnCompleteListener<AuthResult>()
    {
        public String facebookUserId;
        String uid = users.getUid();

        @Override
        public void onComplete(@NotNull Task<AuthResult> task)
        {
            if (!task.isSuccessful())
            {
                Log.w(TAG, "signInWithCredential", task.getException());
                Toast.makeText(FacebookLogin.this, "Authentication failed.",
                        Toast.LENGTH_SHORT).show();
                //Toast.makeText(getApplicationContext(), "Authentication Failed", Toast.LENGTH_SHORT).show();

                // Log.d(TAG, "signInWithCredential:onComplete:" + task.isSuccessful());
            }
            else
            {
                String uid=task.getResult().getUser().getUid();
                String name=task.getResult().getUser().getDisplayName();
                String email=task.getResult().getUser().getEmail();
                String image=task.getResult().getUser().getPhotoUrl().toString();


                Profile profile = Profile.getCurrentProfile();
                facebookUserId = profile.getId();
                String facebookId=facebookUserId;


                User users = new User(uid,name,email,facebookId);
                users.setUserId(uid);
                users.setUserName(name);
                users.setUserEmail(email);
                // mEmailRef = mRootRef.child("users").child(userId).child("email”)
                // Firebase mRefChild = mRef.child("Name").child(uid).child("email");
                mRef.child(uid).setValue(users);

                Intent intent = new Intent(getApplicationContext() ,Home.class);
                intent.putExtra("user_id",uid);
                intent.putExtra("profile_picture",image);

                startActivity(intent);
                finish();
                goMainScreen();
            }
            progressBar.setVisibility(View.VISIBLE);
            loginButton.setVisibility(View.GONE);
        }
    });
}

private void goMainScreen()
{
    Intent intent = new Intent (this, Home.class);
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
    startActivity(intent);
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
    super.onActivityResult(requestCode, resultCode, data);
    callbackManager.onActivityResult(requestCode, resultCode, data);
}

@Override
protected void onStart()
{
    super.onStart();
    firebaseAuth.addAuthStateListener(firebaseAuthListener);
}

@Override
protected void onStop()
{
    super.onStop();
    firebaseAuth.removeAuthStateListener(firebaseAuthListener);
}

public String getUid()
{
    return uid;
}
}

BroadcastFragment.java

public class BroadcastFragment extends Fragment implements DatePickerDialog.OnDateSetListener, TimePickerDialog.OnTimeSetListener{
    int day, month, year, hour, minute;
    int dayFinal, monthFinal, yearFinal, hourFinal, minuteFinal;
    Button deadline;
    EditText reqdesc;
    Button post;
    public String dead="", role="requester", r;
    DatabaseReference dr;
    String uid="", uname="", uemail="";
    User u = new User();

View myView;

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    myView = inflater.inflate(R.layout.broadcast, container, false);
    dr = FirebaseDatabase.getInstance().getReference("BroadcastRequest");


    reqdesc = (EditText) myView.findViewById(R.id.reqdesc);
    deadline = (Button) myView.findViewById(R.id.deadline);
    deadline.setOnClickListener(new View.OnClickListener(){
        @Override
        public void onClick(View v) {
            Calendar c = Calendar.getInstance();
            year = c.get(Calendar.YEAR);
            month = c.get(Calendar.MONTH);
            day = c.get(Calendar.DAY_OF_MONTH);
            DatePickerDialog datePickerDialog = new DatePickerDialog(getActivity(), BroadcastFragment.this,
                    year, month, day);
            datePickerDialog.show();
        }
    });
    post = (Button) myView.findViewById(R.id.post);
    post.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            dead = deadline.getText().toString();
            r = reqdesc.getText().toString();
            uid = u.UserId();
            uname = u.UserName();
            uemail = u.UserEmail();
            writeNewRequest(r, dead, uemail, uid, uname, role, "Siquijor");
            showNotification();
        }
    });


    return myView;
}
private void writeNewRequest(String r, String dead, String email, String id, String name, String role, String cl) {
    DatabaseReference post = dr.push();
    String date = java.text.DateFormat.getDateTimeInstance().format(Calendar.getInstance().getTime());

    post.child("RequestDeadline").setValue(dead);
    post.child("RequestDescription").setValue(r);
    post.child("email").setValue(email);
    post.child("id").setValue(id);
    post.child("name").setValue(name);
    post.child("role").setValue(role);
    post.child("CurrentDateTime").setValue(date);
    post.child("CurrentLocation").setValue(cl);
}

@Override
public void onDateSet(DatePicker view, int year, int month, int dayOfMonth) {
    yearFinal = year;
    monthFinal = month;
    dayFinal = dayOfMonth;

    Calendar c = Calendar.getInstance();
    hour = c.get(Calendar.HOUR_OF_DAY);
    minute = c.get(Calendar.MINUTE);


    TimePickerDialog timePickerDialog = new TimePickerDialog(getActivity(), BroadcastFragment.this,
            hour, minute, DateFormat.is24HourFormat(getActivity()));
    timePickerDialog.show();
}

@Override
public void onTimeSet(TimePicker view, int hourOfDay, int minute) {
    hourFinal = hourOfDay;
    minuteFinal = minute;
    String monthname = monthName(monthFinal);
    String time = midnight(hourFinal,minuteFinal);

    String dl = monthname+" "+dayFinal+" "+yearFinal+" "+time;

    deadline.setText(dl);

}
private String midnight(int h, int m){
    String mid="", hour="";
    if(h<=11){
        mid = "AM";
        if(h==00)
            h=12;
    }
    else if(h>=12){
        mid = "PM";
        if(h>=13)
            h-=12;
    }
    hour = number(h);
    String minute = number(m);
    String t = hour+":"+minute+mid;
    return t;
}
private String number(int n){
    String a = Integer.toString(n);
    if(n<=9){
        a = "0"+a;
        return a;
    }
    else
        return a;
}
private String monthName(int month){
    month+=1;
    String mn="";
    switch (month){
        case 1: mn="January";
            break;
        case 2: mn="February";
            break;
        case 3: mn="March";
            break;
        case 4: mn="April";
            break;
        case 5: mn="May";
            break;
        case 6: mn="June";
            break;
        case 7: mn="July";
            break;
        case 8: mn="August";
            break;
        case 9: mn="September";
            break;
        case 10: mn="October";
            break;
        case 11: mn="November";
            break;
        case 12: mn="December";
            break;
    }
    return mn;
}

public void showNotification(){
    NotificationCompat.Builder builder = new NotificationCompat.Builder(getActivity());
    builder.setSmallIcon(R.mipmap.ic_launcher);
    builder.setContentTitle("PEOPLE HELPER");
    builder.setContentText("Your request has been broadcasted");

    Intent intent = new Intent(getActivity(), BroadcastFragment.class); //creates an explicit intent
    TaskStackBuilder stackBuilder = TaskStackBuilder.create(getActivity());
    stackBuilder.addParentStack(getActivity()); //adds the intent
    stackBuilder.addNextIntent(intent);  //put the intent to the top of the stack
    PendingIntent pendingIntent = stackBuilder.getPendingIntent(0, PendingIntent.FLAG_UPDATE_CURRENT); //(id, flag) //creates a pending intent
    builder.setContentIntent(pendingIntent); //adds the PendingIntent to the builder
    NotificationManager notificationManager = (NotificationManager) getActivity().getSystemService(Context.NOTIFICATION_SERVICE);
    notificationManager.notify(0, builder.build());
}

}

User.java

public class User {
    public String uid;
    public String name;
    public String email;
    public String facebookId;

    public User(){

    }

    public User(String uid, String name, String email, String facebookId)
    {
        this.uid = uid;
        this.name = name;
        this.email = email;
        this.facebookId = facebookId;
    }
    public void setUserId(String uid)
    {
        this.uid = uid;
    }
    public void setUserName(String name){
        this.name = name;
    }
    public void setUserEmail(String email){
        this.email = email;
    }
    public String UserId(){
        return uid;
    }
    public String UserName(){
        return name;
    }
    public String UserEmail(){
        return email;
    }
}