Question

在以下代码中，我尝试打开“登录”页面。用户将填写电子邮件和密码。当用户单击登录按钮时，将调用onComplete方法。

我理解在package com.awani.pocketblog; import android.app.ProgressDialog; import android.content.Intent; import android.support.annotation.NonNull; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.text.TextUtils; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.Toast; import com.google.android.gms.tasks.OnCompleteListener; import com.google.android.gms.tasks.Task; import com.google.firebase.auth.AuthResult; import com.google.firebase.auth.FirebaseAuth; 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 LoginActivity extends AppCompatActivity { private EditText mLoginEmailField; private EditText mLoginPasswordField; private Button mLoginButton; private Button mNewAccountButton; private FirebaseAuth mAuth; private ProgressDialog mProgress; private DatabaseReference mDatabaseUsers; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_login); mAuth = FirebaseAuth.getInstance(); mDatabaseUsers = FirebaseDatabase.getInstance().getReference().child("Users"); mDatabaseUsers.keepSynced(true); mLoginEmailField = (EditText) findViewById(R.id.loginEmailField); mLoginPasswordField = (EditText) findViewById(R.id.loginPaswordField); mLoginButton = (Button) findViewById(R.id.loginButton); mNewAccountButton = (Button) findViewById(R.id.newAccountButton); mProgress = new ProgressDialog(this); mLoginButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { checkLogin(); } }); } private void checkLogin() { //retrieve the data from database to check if user is logged in correctly String email = mLoginEmailField.getText().toString().trim(); String password = mLoginPasswordField.getText().toString().trim(); if (!TextUtils.isEmpty(email) && !TextUtils.isEmpty(password)) { mProgress.setMessage("Checking Login..."); mProgress.show(); mAuth.signInWithEmailAndPassword(email, password).addOnCompleteListener(new OnCompleteListener < AuthResult > () { @Override public void onComplete(@NonNull Task < AuthResult > task) { //the following if block is never executed....WHY? if (task.isSuccessful()) { // Toast.makeText(LoginActivity.this,"hi",Toast.LENGTH_LONG).show(); checkUserExist(); } else { mProgress.dismiss(); Toast.makeText(LoginActivity.this, "Error Login", Toast.LENGTH_LONG).show(); } } }); } } private void checkUserExist() { //retrieving UID final String user_id = mAuth.getCurrentUser().getUid(); //check if the user with thi UID already exists mDatabaseUsers.addValueEventListener(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { if (dataSnapshot.hasChild(user_id)) { Intent mainIntent = new Intent(LoginActivity.this, MainActivity.class); mainIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); startActivity(mainIntent); } else { Intent setUpIntent = new Intent(LoginActivity.this, SetUpActivity.class); setUpIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); startActivity(setUpIntent); } } @Override public void onCancelled(DatabaseError databaseError) { } }); } }方法中，不会调用第1个if块检查成功（填写电子邮件，密码和单击登录）。我总是收到Toast消息“Error login”（else块）。

has_many :users association

Answer 1

转到您的firebase控制台，启用登录方式：Email/Password或Anonymous

如果它不起作用，请编辑您的密码，也许它太短了。

Answer 2

要使用电子邮件/密码进行身份验证，必须先使用createUserWithEmailAndPassword()创建用户：

尝试使用给定的电子邮件地址创建新的用户帐户密码。如果成功，它还会将用户签入应用程序

此示例在guide for password-based authentication：

的第4步中提供

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();
                    updateUI(user);
                } else {
                    // If sign in fails, display a message to the user.
                    Log.w(TAG, "createUserWithEmail:failure", task.getException());
                    Toast.makeText(EmailPasswordActivity.this, "Authentication failed.",
                            Toast.LENGTH_SHORT).show();
                    updateUI(null);
                }

                // ...
            }
        });

无法成功完成身份验证

2 个答案: