Firebase Google身份验证

Question

Code

    private String mEmail;
    private FirebaseUser current_user;

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

    mEmail = current_user.getEmail();

This is getting a Null Pointer exception but the below fetches properly

    UID = current_user.getUid();

Why is that??? and in a different activity...

    private void setUserData(FirebaseUser user) {
    nameTextView.setText(user.getDisplayName());
    emailTextView.setText(user.getEmail());
    idTextView.setText(user.getUid());
    Glide.with(this).load(user.getPhotoUrl()).into(photoImageView);
}

This fetches email without any problem... Why is that the same method behaving differently in different activities

Im using gmail signin for auth

Answer 1

我认为您必须像这样初始化current_user

current_user =FirebaseAuth.getInstance().getCurrentUser();