Android StudioにてJAVAをつかったGoogleアカウント認証

前提・実現したいこと

Android StudioでJAVAを使ったアプリ開発をしています。
ユーザー登録の際に
グーグル認証を使った新規ユーザのアカウント登録とログインをしたいのですが
どうしてもエラーが解決できません。

ユーザーがログインするLOGINとログイン後にユーザの情報が表示されるMYPAGE二つのページで構成されています。

発生している問題・エラーメッセージ

@Override
protected void onStart() {
super.onStart();

    FirebaseUser user = mAuth.**getCurrentUser();**
    if(user!=null){
        Intent intent = new Intent(getApplicationContext(), ContactsContract.Profile.class);
        startActivity(intent);
    }

private void firebaseAuthWithGoogle(GoogleSignInAccount acct) {

    AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
    mAuth.**signInWithCredential**(credential)
            .addOnCompleteListener(this, new OnCompleteListener() {
                @Override
                public void onComplete(@NonNull Task task) {
                    if (task.isSuccessful()) {
                        // Sign in success, update UI with the signed-in user's information
                        FirebaseUser user = mAuth.**getCurrentUser();**
                        Intent intent = new Intent(getApplicationContext(), ContactsContract.Profile.class);
                        startActivity(intent);


                    } else {
                        Toast.makeText(LoginActivity.this, "Sorry auth failed.", Toast.LENGTH_SHORT).show();


                    }

上記太字の部分が解決できないメソッドとしてエラーになります。

該当のソースコード

Java
1package com.example.alertappfyp2.ui.login;
2
3
4public class LoginActivity extends AppCompatActivity {
5
6
7    private GoogleSignInClient mGoogleSignInClient;
8    private final static int RC_SIGN_IN = 123;
9    private FirebaseAuth mAuth;
10
11
12    @Override
13    protected void onStart() {
14        super.onStart();
15
16
17        FirebaseUser user = mAuth.**getCurrentUser();**
18        if(user!=null){
19            Intent intent = new Intent(getApplicationContext(), ContactsContract.Profile.class);
20            startActivity(intent);
21        }
22
23
24    }
25
26
27    @Override
28    protected void onCreate(Bundle savedInstanceState) {
29        super.onCreate(savedInstanceState);
30        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
31        setContentView(R.layout.activity_main);
32
33
34        mAuth = FirebaseAuth.getInstance();
35
36
37        createRequest();
38
39
40        findViewById(R.id.login).setOnClickListener(new View.OnClickListener() {
41            @Override
42            public void onClick(View view) {
43                signIn();
44            }
45        });
46
47
48    }
49
50
51    private void createRequest() {
52
53
54        // Configure Google Sign In
55        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
56                .requestIdToken(getString(R.string.default_web_client_id))
57                .requestEmail()
58                .build();
59
60
61        // Build a GoogleSignInClient with the options specified by gso.
62        mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
63
64
65    }
66
67
68    private void signIn() {
69        Intent signInIntent = mGoogleSignInClient.getSignInIntent();
70        startActivityForResult(signInIntent, RC_SIGN_IN);
71    }
72
73
74    @Override
75    public void onActivityResult(int requestCode, int resultCode, Intent data) {
76        super.onActivityResult(requestCode, resultCode, data);
77
78
79        // Result returned from launching the Intent from GoogleSignInApi.getSignInIntent(...);
80        if (requestCode == RC_SIGN_IN) {
81            Task task = GoogleSignIn.getSignedInAccountFromIntent(data);
82            try {
83                // Google Sign In was successful, authenticate with Firebase
84                GoogleSignInAccount account = (GoogleSignInAccount) task.getResult(ApiException.class);
85                firebaseAuthWithGoogle(account);
86            } catch (Throwable e) {
87                // Google Sign In failed, update UI appropriately
88                // ...
89                Toast.makeText(this, e.getMessage(), Toast.LENGTH_SHORT).show();
90            }
91        }
92    }
93
94
95    private void firebaseAuthWithGoogle(GoogleSignInAccount acct) {
96
97
98        AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
99        mAuth.**signInWithCredential**(credential)
100                .addOnCompleteListener(this, new OnCompleteListener() {
101                    @Override
102                    public void onComplete(@NonNull Task task) {
103                        if (task.isSuccessful()) {
104                            // Sign in success, update UI with the signed-in user's information
105                            FirebaseUser user = mAuth.getCurrentUser();
106                            Intent intent = new Intent(getApplicationContext(), ContactsContract.Profile.class);
107                            startActivity(intent);
108
109
110                        } else {
111                            Toast.makeText(LoginActivity.this, "Sorry auth failed.", Toast.LENGTH_SHORT).show();
112
113
114                        }
115
116
117                        // ...
118                    }
119                });
120    }
121
122
123}

Java
1
2public class MyPage extends AppCompatActivity {
3
4    ImageView img;
5    TextView name,Age,pol;
6    Button LB;
7
8    FirebaseAuth mAuth;
9    GoogleSignInClient mGoogleSignInClient;
10
11    @Override
12    protected void onCreate(Bundle savedInstanceState) {
13        super.onCreate(savedInstanceState);
14        setContentView(R.layout.activity_my_page);
15
16        img=findViewById(R.id.img);
17        name=findViewById(R.id.name);
18        Age=findViewById(R.id.Age);
19        pol=findViewById(R.id.pol);
20        LB=findViewById(R.id.lb);
21
22        GoogleSignInAccount signInAccount = GoogleSignIn.getLastSignedInAccount(this);
23        if(signInAccount != null){
24            name.setText(signInAccount.getDisplayName());
25            Age.setText(signInAccount.getEmail());
26        }
27
28
29        LB.setOnClickListener(new View.OnClickListener() {
30            @Override
31            public void onClick(View view) {
32                FirebaseAuth.getInstance().signOut();
33                Intent intent = new Intent(getApplicationContext(),MainActivity.class);
34                startActivity(intent);
35            }
36        });
37                    }
38                }
39
40
41

grade
1// Top-level build file where you can add configuration options common to all sub-projects/modules.
2
3buildscript {
4    repositories {
5        google()
6        jcenter()
7        
8    }
9    dependencies {
10        classpath 'com.android.tools.build:gradle:4.1.2'
11        classpath 'com.google.gms:google-services:4.3.5'
12        
13        // NOTE: Do not place your application dependencies here; they belong
14        // in the individual module build.gradle files
15    }
16}
17
18allprojects {
19    repositories {
20        google()
21        jcenter()
22        
23    }
24}
25

grade
1apply plugin: 'com.android.application'
2
3android {
4    compileSdkVersion 29
5    buildToolsVersion "29.0.2"
6    defaultConfig {
7        applicationId "com.example.alertappfyp2"
8        minSdkVersion 29
9        targetSdkVersion 29
10        versionCode 1
11        versionName "1.0"
12        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
13        vectorDrawables.useSupportLibrary = true
14    }
15    buildTypes {
16        release {
17            minifyEnabled false
18            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
19        }
20    }
21}
22
23dependencies {
24    implementation fileTree(dir: 'libs', include: ['*.jar'])
25    implementation 'androidx.appcompat:appcompat:1.0.2'
26    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
27    implementation 'com.google.android.material:material:1.0.0'
28    implementation 'androidx.annotation:annotation:1.0.2'
29    implementation 'androidx.lifecycle:lifecycle-extensions:2.2.0'
30    implementation 'androidx.preference:preference:1.1.0-alpha05'
31    implementation 'androidx.vectordrawable:vectordrawable:1.0.1'
32    implementation 'androidx.navigation:navigation-fragment:2.0.0'
33    implementation 'androidx.navigation:navigation-ui:2.0.0'
34    implementation platform('com.google.firebase:firebase-bom:26.4.0')
35    implementation 'com.google.firebase:firebase-messaging:'
36    implementation 'com.google.firebase:firebase-analytics'
37    implementation 'com.google.firebase:firebase-core'
38    implementation 'com.google.firebase:firebase-admin:7.1.0'
39    implementation 'com.google.firebase:firebase-auth:19.2.0'
40    implementation "com.firebaseui:firebase-ui-auth:7.1.1"
41    implementation 'com.google.android.gms:play-services-auth:19.0.0'
42    implementation 'com.github.bumptech.glide:glide:4.4.0'
43    testImplementation 'junit:junit:4.12'
44    androidTestImplementation 'androidx.test:runner:1.1.1'
45    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
46}
47
48apply plugin: 'com.google.gms.google-services'
49
50