Firebase电子邮件/密码验证未在Android St上注册用户

Question

我正在使用需要使用Firebase进行用户身份验证的android应用程序。我创建了一个测试活动，其中只有两个用于用户身份验证的字段（电子邮件和密码）。但是每次我输入电子邮件和密码并单击注册按钮时，都会显示吐司“无法注册”

这是我的注册活动：

package com.example.u.locationtracker;

import android.app.ProgressDialog;
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.ProgressBar;
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;

public class Register extends AppCompatActivity implements View.OnClickListener {

    private EditText eemail, epass;
    private Button bregist;

    private ProgressDialog progressDialog;

    private FirebaseAuth firebaseAuth;

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

        progressDialog = new ProgressDialog(this);

        firebaseAuth = FirebaseAuth.getInstance();

        eemail = (EditText) findViewById(R.id.etemail);
        epass = (EditText) findViewById(R.id.etpass);

        bregist = (Button) findViewById(R.id.btnreg);

        bregist.setOnClickListener(this);

    }

    private void registerUser() {
        String Email = eemail.getText().toString().trim();
        String Pass = epass.getText().toString().trim();

        if (TextUtils.isEmpty(Email)) {
            Toast.makeText(getApplicationContext(), "Enter the Email First",
                    Toast.LENGTH_LONG).show();
            return;
        }
        if (TextUtils.isEmpty(Pass)) {
            Toast.makeText(getApplicationContext(), "Enter the Password First",
                    Toast.LENGTH_LONG).show();
            return;
        }

        progressDialog.setMessage("Signing in");
        progressDialog.show();

        firebaseAuth.createUserWithEmailAndPassword(Email, Pass)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {
                            Toast.makeText(getApplicationContext(), "Registration Successfull",
                                    Toast.LENGTH_LONG).show();
                        } else {
                            Toast.makeText(getApplicationContext(), "Can not Registered",
                                    Toast.LENGTH_LONG).show();
                        }
                    }
                });
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btnreg:
                registerUser();
                break;
        }
    }
}

应用程序级别buld.gradle在这里：

apply plugin: 'com.android.application'

android {
    compileSdkVersion 28
    defaultConfig {
        applicationId "com.example.u.locationtracker"
        minSdkVersion 17
        targetSdkVersion 28
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:28.0.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
    implementation 'com.google.firebase:firebase-core:16.0.1'
    implementation 'com.google.firebase:firebase-auth:16.0.1'
}
apply plugin: 'com.google.gms.google-services'

android studio也在此行显示错误，但可以正常工作：

implementation 'com.android.support:appcompat-v7:28.0.0'

我希望有人可以帮助我解决这个问题