Gmail Integration using Android and Firebase

Gmail Integration using Android and Firebase

Output Screen

add dependency in Gradle

    

implementation 'com.google.firebase:firebase-auth:19.3.2'

implementation 'com.google.android.gms:play-services-auth:18.1.0'
implementation 'com.github.bumptech.glide:glide:4.8.0'
annotationProcessor 'com.github.bumptech.glide:compiler:4.8.0'

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 

xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <com.google.android.gms.common.SignInButton
        android:id="@+id/google_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.0" />
    />
</androidx.constraintlayout.widget.ConstraintLayout>

activity_home_page.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    xmlns:android="http://schemas.android.com/apk/res/android">

    <ImageView
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:src="@drawable/ic_launcher_background"
        android:scaleType="centerCrop"
        android:layout_gravity="center"
        android:id="@+id/myimage"/>

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/myid"
        android:layout_marginTop="20dp"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Logout"
        android:onClick="logout"/>

</LinearLayout>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.firebasedemo">

    <uses-permission-sdk-23 android:name="android.permission.INTERNET" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:name=".SingleTask"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".HomePage"></activity>
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

SingleTask.java

package com.example.firebasedemo;

import android.app.Application;

import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInClient;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;

public class SingleTask extends Application {
    private GoogleSignInClient mGoogleSignInClient;

    @Override
    public void onCreate() {
        super.onCreate();
        GoogleSignInOptions gso = new GoogleSignInOptions.

        Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestIdToken(getString(R.string.default_web_client_id))
                .requestEmail()
                .build();
        mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
    }

    public GoogleSignInClient getmGoogleSignInClient() {
        return mGoogleSignInClient;
    }
}

MainActivity.java

package com.example.firebasedemo;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthCredential;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.auth.GoogleAuthProvider;
import com.google.android.gms.common.SignInButton;

public class MainActivity extends AppCompatActivity {
    private FirebaseAuth mAuth;
    private SingleTask singleTask;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mAuth = FirebaseAuth.getInstance();

        singleTask = (SingleTask) getApplication();

        SignInButton signbutton = findViewById(R.id.google_button);
        signbutton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                signIn();
            }
        });
    }

    @Override
    protected void onStart() {
        super.onStart();
        FirebaseUser user = mAuth.getCurrentUser();
        if (user != null) {
            goToHomePage();
        }
    }

    private void signIn() {
        Intent signInIntent = singleTask.getmGoogleSignInClient().

        getSignInIntent();
        startActivityForResult(signInIntent, 1001);
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        
        if (requestCode == 1001) {
            Task<GoogleSignInAccount> task = GoogleSignIn.

            getSignedInAccountFromIntent(data);
            try {
                // Google Sign In was successful, authenticate with Firebase
                GoogleSignInAccount account = task.getResult(ApiException.class);
                firebaseAuthWithGoogle(account.getIdToken());
            } catch (ApiException e) {
                // Google Sign In failed, update UI appropriately
                Log.w("error", "Google sign in failed", e);
            }
        }
    }

    private void firebaseAuthWithGoogle(String idToken) {
        AuthCredential credential = GoogleAuthProvider.

        getCredential(idToken, null);
        mAuth.signInWithCredential(credential)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {
                            goToHomePage();
                        } else {
                        Log.w("error", "signInWithCredential:failure", 

                        task.getException());

                        }
                    }
                });
    }

    private void goToHomePage() {
        Intent in = new Intent(MainActivity.this, HomePage.class);
        startActivity(in);
        finish();
    }

}

HomePage.java

package com.example.firebasedemo;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.TextView;

import com.bumptech.glide.Glide;
import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInClient;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;

public class HomePage extends AppCompatActivity {
    private FirebaseAuth mAuth;
    private SingleTask singleTask;

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

        ImageView image = findViewById(R.id.imageprofile);
        TextView detail = findViewById(R.id.detail);

        mAuth = FirebaseAuth.getInstance();
        FirebaseUser user = mAuth.getCurrentUser();

        if (user != null) {
            Glide.with(this).load(user.getPhotoUrl()).into(image);
            detail.setText(user.getDisplayName() + "\n" + 

    user.getEmail() + "\n" + user.getUid() + "\n" + user.getProviderId());
        }

        singleTask = (SingleTask) getApplication();

    }

    public void logout(View view) {
        mAuth.signOut();
        singleTask.getmGoogleSignInClient().signOut().

    addOnCompleteListener(new OnCompleteListener<Void>() {

            @Override
            public void onComplete(@NonNull Task<Void> task) {
                if (task.isSuccessful()) {
                    Intent in = new Intent(HomePage.this, MainActivity.class);
                    startActivity(in);
                    finish();
                }
            }
        });

    }
}