Step 1: Login to google developers console and create new project inside it now after adding required info you need to enable google+ api under its section enable it.
Step 2. Now create new project in android studio. Open your project gradle we need to add dependencies in your build.gradle.
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:22.2.0'
compile 'com.google.android.gms:play-services:7.5.0'
}
Step 3. Open project Manifest file add permissions in it.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.googlepluszetaintegration">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.USE_CREDENTIALS" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme">
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" />
<activity
android:name=".MainActivity"
android:label="Trinity Google+">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Step 4. Now open your Layout file where we add some button and textview to login and show logged user data.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="16dp"
tools:context=".MainActivity" >
<LinearLayout
android:id="@+id/llProfile"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="20dp"
android:orientation="horizontal"
android:weightSum="3"
android:visibility="gone">
<ImageView
android:id="@+id/imgProfilePic"
android:layout_width="150dp"
android:layout_height="150dp"
android:layout_weight="1"/>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:orientation="vertical"
android:layout_weight="2" >
<TextView
android:id="@+id/txtName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="5dp"
android:textSize="20dp" />
<TextView
android:id="@+id/txtEmail"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="5dp"
android:textSize="18dp" />
<TextView
android:id="@+id/token"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="5dp"
android:textSize="18dp" />
</LinearLayout>
</LinearLayout>
<com.google.android.gms.common.SignInButton
android:id="@+id/btn_sign_in"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="20dp"/>
<Button
android:id="@+id/btn_sign_out"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/btn_logout_from_google"
android:visibility="gone"
android:layout_marginBottom="10dp"/>
<Button
android:id="@+id/btn_revoke_access"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/btn_revoke_access"
android:visibility="gone" />
</LinearLayout>
Step 5. Now add following given below code in your activity to complete your login.
public class MainActivity extends Activity implements
ConnectionCallbacks, OnConnectionFailedListener, View.OnClickListener {
private static final int RC_SIGN_IN = 0;
// Logcat tag
private static final String TAG = "MainActivity";
// Profile pic image size in pixels
private static final int PROFILE_PIC_SIZE = 400;
// Google client to interact with Google API
private GoogleApiClient mGoogleApiClient;
/**
* A flag indicating that a PendingIntent is in progress and prevents us
* from starting further intents.
*/
private boolean mIntentInProgress;
private boolean mSignInClicked;
private ConnectionResult mConnectionResult;
private SignInButton btnSignIn;
private Button btnSignOut, btnRevokeAccess;
private ImageView imgProfilePic;
private TextView txtName, txtEmail,token;
private LinearLayout llProfileLayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnSignIn = (SignInButton) findViewById(R.id.btn_sign_in);
btnSignOut = (Button) findViewById(R.id.btn_sign_out);
btnRevokeAccess = (Button) findViewById(R.id.btn_revoke_access);
imgProfilePic = (ImageView) findViewById(R.id.imgProfilePic);
txtName = (TextView) findViewById(R.id.txtName);
txtEmail = (TextView) findViewById(R.id.txtEmail);
llProfileLayout = (LinearLayout) findViewById(R.id.llProfile);
token=(TextView)findViewById(R.id.token);
// Button click listeners
btnSignIn.setOnClickListener(this);
btnSignOut.setOnClickListener(this);
btnRevokeAccess.setOnClickListener(this);
// Initializing google plus api client
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this).addApi(Plus.API,new Plus.PlusOptions.Builder().build())
.addScope(Plus.SCOPE_PLUS_LOGIN).build();
}
protected void onStart() {
super.onStart();
mGoogleApiClient.connect();
}
protected void onStop() {
super.onStop();
if (mGoogleApiClient.isConnected()) {
mGoogleApiClient.disconnect();
}
}
/**
* Button on click listener
*/
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.btn_sign_in:
// Signin button clicked
signInWithGplus();
break;
case R.id.btn_sign_out:
// Signout button clicked
signOutFromGplus();
break;
case R.id.btn_revoke_access:
// Revoke access button clicked
revokeGplusAccess();
break;
}
}
private void revokeGplusAccess() {
if (mGoogleApiClient.isConnected()) {
Plus.AccountApi.clearDefaultAccount(mGoogleApiClient);
Plus.AccountApi.revokeAccessAndDisconnect(mGoogleApiClient)
.setResultCallback(new ResultCallback<Status>() {
@Override
public void onResult(Status arg0) {
Log.e(TAG, "User access revoked!");
mGoogleApiClient.connect();
updateUI(false);
}
});
}
}
private void signOutFromGplus() {
if (mGoogleApiClient.isConnected()) {
Plus.AccountApi.clearDefaultAccount(mGoogleApiClient);
mGoogleApiClient.disconnect();
mGoogleApiClient.connect();
updateUI(false);
}
}
/**
* Sign-in into google
*/
private void signInWithGplus() {
if (!mGoogleApiClient.isConnecting()) {
mSignInClicked = true;
resolveSignInError();
}
}
/**
* Method to resolve any signin errors
*/
private void resolveSignInError() {
if (mConnectionResult.hasResolution()) {
try {
mIntentInProgress = true;
mConnectionResult.startResolutionForResult(this, RC_SIGN_IN);
} catch (IntentSender.SendIntentException e) {
mIntentInProgress = false;
mGoogleApiClient.connect();
}
}
}
@Override
public void onConnectionFailed(ConnectionResult result) {
if (!result.hasResolution()) {
GooglePlayServicesUtil.getErrorDialog(result.getErrorCode(), this,
0).show();
return;
}
if (!mIntentInProgress) {
// Store the ConnectionResult for later usage
mConnectionResult = result;
if (mSignInClicked) {
// The user has already clicked 'sign-in' so we attempt to
// resolve all
// errors until the user is signed in, or they cancel.
resolveSignInError();
}
}
}
@Override
protected void onActivityResult(int requestCode, int responseCode,
Intent intent) {
if (requestCode == RC_SIGN_IN) {
if (responseCode != RESULT_OK) {
mSignInClicked = false;
}
mIntentInProgress = false;
if (!mGoogleApiClient.isConnecting()) {
mGoogleApiClient.connect();
}
}
}
@Override
public void onConnected(Bundle arg0) {
mSignInClicked = false;
Toast.makeText(this, "User is connected!", Toast.LENGTH_LONG).show();
// Get user's information
getProfileInformation();
// Update the UI after signin
updateUI(true);
}
/**
* Fetching user's information name, email, profile pic
*/
private void getProfileInformation() {
try {
if (Plus.PeopleApi.getCurrentPerson(mGoogleApiClient) != null) {
Person currentPerson = Plus.PeopleApi
.getCurrentPerson(mGoogleApiClient);
String personName = currentPerson.getDisplayName();
String personPhotoUrl = currentPerson.getImage().getUrl();
String personGooglePlusProfile = currentPerson.getUrl();
String email = Plus.AccountApi.getAccountName(mGoogleApiClient);
Log.e(TAG, "Name: " + personName + ", plusProfile: "
+ personGooglePlusProfile + ", email: " + email
+ ", Image: " + personPhotoUrl+"====="+ currentPerson.getId().toString()+"=====");
txtName.setText(personName);
txtEmail.setText(email);
// by default the profile url gives 50x50 px image only
// we can replace the value with whatever dimension we want by
// replacing sz=X
personPhotoUrl = personPhotoUrl.substring(0,
personPhotoUrl.length() - 2)
+ PROFILE_PIC_SIZE;
new LoadProfileImage(imgProfilePic).execute(personPhotoUrl);
AsyncTask<Void, Void, String > task = new AsyncTask<Void, Void, String>() {
@Override
protected String doInBackground(Void... params) {
String token = null;
final String SCOPES = "https://www.googleapis.com/auth/plus.login ";
try {
token = GoogleAuthUtil.getToken(
getApplicationContext(),
Plus.AccountApi.getAccountName(mGoogleApiClient),
"oauth2:" + SCOPES);
} catch (IOException e) {
e.printStackTrace();
} catch (GoogleAuthException e) {
e.printStackTrace();
}
catch (IllegalStateException e){
e.printStackTrace();
}
return token;
}
@Override
protected void onPostExecute(String tokens) {
token.setText("Token Access "+tokens);
Log.e(TAG, "Access token retrieved:" + tokens);
}
};
task.execute();
} else {
Toast.makeText(getApplicationContext(),
"Person information is null", Toast.LENGTH_LONG).show();
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Background Async task to load user profile picture from url
*/
private class LoadProfileImage extends AsyncTask<String, Void, Bitmap> {
ImageView bmImage;
public LoadProfileImage(ImageView bmImage) {
this.bmImage = bmImage;
}
protected Bitmap doInBackground(String... urls) {
String urldisplay = urls[0];
Bitmap mIcon11 = null;
try {
InputStream in = new java.net.URL(urldisplay).openStream();
mIcon11 = BitmapFactory.decodeStream(in);
} catch (Exception e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return mIcon11;
}
protected void onPostExecute(Bitmap result) {
bmImage.setImageBitmap(result);
}
}
@Override
public void onConnectionSuspended(int arg0) {
mGoogleApiClient.connect();
updateUI(false);
}
/**
* Updating the UI, showing/hiding buttons and profile layout
*/
private void updateUI(boolean isSignedIn) {
if (isSignedIn) {
btnSignIn.setVisibility(View.GONE);
btnSignOut.setVisibility(View.VISIBLE);
btnRevokeAccess.setVisibility(View.VISIBLE);
llProfileLayout.setVisibility(View.VISIBLE);
} else {
btnSignIn.setVisibility(View.VISIBLE);
btnSignOut.setVisibility(View.GONE);
btnRevokeAccess.setVisibility(View.GONE);
llProfileLayout.setVisibility(View.GONE);
}
}
}
Now once you complete above steps your app is ready to login user with google+.
🙂