我已经使用firebase将google登录到我的应用中。但是当我使用谷歌登录时，它会正常登录，然后在我的主要活动中崩溃，因为我需要用户ID并且xant发现它在我的日志中发现此错误
java.lang.String com.google.firebase.auth.FirebaseUser.getUid()' on a null object reference
如果我使用电子邮件登录，然后使用Google帐户登录，则会从电子邮件中删除我的密码，并且不允许我再次使用我的电子邮件进行身份验证，除非我删除了我的帐户。
我的登录代码是
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//hides keyboard on start;
getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);
setContentView(com.example.harrops.h20droidapp2.R.layout.activity_login);
Intent intent = new Intent(Login.this, UpdateService.class);
startService(intent);
mAuth = FirebaseAuth.getInstance();
cbrememberme = (CheckBox) findViewById(R.id.cbrememberme);
mgo = (Button) findViewById(R.id.btnsubmit);
mgo.setText("Login");
memail = (EditText) findViewById(R.id.etemail);
mpass = (EditText) findViewById(R.id.etpass);
mforgot = (TextView) findViewById(R.id.tvforgotpass);
mreset = (Button) findViewById(R.id.btnreset);
mmember = (CheckBox) findViewById(R.id.cbexisiting);
loginPreferences = getSharedPreferences("loginPrefs", MODE_PRIVATE);
loginPrefsEditor = loginPreferences.edit();
saveLogin = loginPreferences.getBoolean("saveLogin", false);
if (saveLogin == true) {
memail.setText(loginPreferences.getString("username", ""));
mpass.setText(loginPreferences.getString("password", ""));
cbrememberme.setChecked(true);
signinnorm();
}
mmember.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (mmember.isChecked() == false) {
mgo.setText("Sign in");
memail.setHint("Sign up with a a valid email address");
} else {
mgo.setText("Register");
mpass.setHint("Enter new password");
}
}
});
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(getString(R.string.default_web_client_id))
.requestEmail()
.build();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addApi(Auth.GOOGLE_SIGN_IN_API, gso)
.build();
SignInButton signInButton = (SignInButton) findViewById(R.id.sign_in_button);
findViewById(R.id.sign_in_button).setOnClickListener(this);
signInButton.setSize(SignInButton.SIZE_STANDARD);
mreset.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mreset.setVisibility(View.GONE);
mpass.setVisibility(View.VISIBLE);
ResetPassword();
}
});
mforgot.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mpass.setVisibility(View.GONE);
mreset.setVisibility(View.VISIBLE);
}
});
mgo.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (!mmember.isChecked()) {
signinnorm();
} else {
signup();
}
}
});
}
private void signup() {
String email;
String password;
email = memail.getText().toString().trim();
password = mpass.getText().toString().trim();
if (TextUtils.isEmpty(email) || TextUtils.isEmpty(password)) {
memail.setHint(getString(R.string.ENTERYOUREMAIL));
memail.setHintTextColor(RED);
mpass.setHint(getString(R.string.ENTERYOURPASSWORD));
mpass.setHintTextColor(RED);
} else {
mAuth.createUserWithEmailAndPassword(email, password)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
@Override
public void onComplete(@NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
// Sign in success, update UI with the signed-in user's information
Log.d(TAG, "createUserWithEmail:success");
FirebaseUser user = mAuth.getCurrentUser();
mmember.setChecked(false);
cbrememberme.setChecked(true);
Toast.makeText(Login.this, "Thanks for signing up. click login in to continue", Toast.LENGTH_SHORT);
;
} else {
// If sign in fails, display a message to the user.
Log.w(TAG, "createUserWithEmail:failure", task.getException());
Toast.makeText(Login.this, "Authentication failed.",
Toast.LENGTH_SHORT).show();
}
}
});
}
}
private void signinnorm() {
String email = memail.getText().toString().trim();
String password = mpass.getText().toString().trim();
if (cbrememberme.isChecked()) {
loginPrefsEditor.putBoolean("saveLogin", true);
loginPrefsEditor.putString("username", email);
loginPrefsEditor.putString("password", password);
loginPrefsEditor.commit();
} else {
loginPrefsEditor.clear();
loginPrefsEditor.commit();
}
if (TextUtils.isEmpty(email) || TextUtils.isEmpty(password)) {
memail.setHint(getString(R.string.ENTERYOUREMAIL));
memail.setHintTextColor(RED);
mpass.setHint(getString(R.string.ENTERYOURPASSWORD));
mpass.setHintTextColor(RED);
} else {
mAuth.signInWithEmailAndPassword(email, password)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
@Override
public void onComplete(@NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
// Sign in success, update UI with the signed-in user's information
Log.d(TAG, "signInWithEmail:success");
FirebaseUser user = mAuth.getCurrentUser();
startActivity(new Intent(Login.this, MainActivity.class));
finish();
} else {
// If sign in fails, display a message to the user.
Log.w(TAG, "signInWithEmail:failure", task.getException());
Toast.makeText(Login.this, "Authentication failed.",
Toast.LENGTH_SHORT).show();
}
}
});
}
}
private void ResetPassword() {
FirebaseAuth auth = FirebaseAuth.getInstance();
String emailAddress;
emailAddress = memail.getText().toString().trim();
auth.sendPasswordResetEmail(emailAddress)
.addOnCompleteListener(new OnCompleteListener<Void>() {
@Override
public void onComplete(@NonNull Task<Void> task) {
if (task.isSuccessful()) {
Log.d(TAG, "Email sent.");
}
}
});
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.sign_in_button:
signIn();
break;
}
}
private void signIn() {
Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
startActivityForResult(signInIntent, RC_SIGN_IN);
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// Result returned from launching the Intent from GoogleSignInApi.getSignInIntent(...);
if (requestCode == RC_SIGN_IN) {
GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
handleSignInResult(result);
}
}
private void handleSignInResult(GoogleSignInResult result) {
if (result.isSuccess()) {
GoogleSignInAccount account = result.getSignInAccount();
firebaseAuthWithGoogle(account);
startActivity(new Intent(Login.this, MainActivity.class));
} else {
// Signed out, show unauthenticated UI.
}
}
private void firebaseAuthWithGoogle(GoogleSignInAccount acct) {
Log.d(TAG, "firebaseAuthWithGoogle:" + acct.getId());
AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
mAuth.signInWithCredential(credential)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
@Override
public void onComplete(@NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
// Sign in success, update UI with the signed-in user's information
Log.d(TAG, "signInWithCredential:success");
FirebaseUser user = mAuth.getCurrentUser();
} else {
// If sign in fails, display a message to the user.
Log.w(TAG, "signInWithCredential:failure", task.getException());
Toast.makeText(Login.this, "Authentication failed.",
Toast.LENGTH_SHORT).show();
}
// ...
}
});
}
然后在我的主要活动中，我调用用户id在oncreate中调用此方法
private void GetUser_Firebase() {
user = FirebaseAuth.getInstance().getCurrentUser();
userid = user.getUid();
DatabaseReference ref1 = mrootRef.getReference();
mloggedinas = (TextView) findViewById(R.id.tvloggedin);
ref1.child("User").child(userid).addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
String m = dataSnapshot.child("screenname").getValue(String.class);
if (m == null) {
Toast.makeText(MainActivity.this, "Please fill in the above fields", Toast.LENGTH_LONG).show();
startActivity(new Intent(MainActivity.this, Edit_profile.class));
} else {
mloggedinas.setText(m);
}
}
EDIT ****** 我可以在我的主要活动上使用此方法而不是登录活动吗？ 这是来自firebase网站？
private void firebaseAuthWithGoogle(GoogleSignInAccount acct) {
Log.d(TAG, "firebaseAuthWithGoogle:" + acct.getId());
AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
mAuth.signInWithCredential(credential)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
@Override
public void onComplete(@NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
// Sign in success, update UI with the signed-in user's information
Log.d(TAG, "signInWithCredential:success");
FirebaseUser user = mAuth.getCurrentUser();
updateUI(user);
} else {
// If sign in fails, display a message to the user.
Log.w(TAG, "signInWithCredential:failure", task.getException());
Toast.makeText(GoogleSignInActivity.this, "Authentication failed.",
Toast.LENGTH_SHORT).show();
updateUI(null);
}
// ...
}
});
}
答案 0 :(得分：0)
通过在注册时调用get user id方法而不是我的主要活动来解决没有它的问题。
我把它放在google auth方法onSuccess
中