How to get profile like gender from google signin in Android?

The Plus people stuff is deprecated, don't use it anymore. The way to do this is with the Google People API Enable this API in your project. If you don't, the exception thrown in Studio includes a link directly to your project to enable it (nice).

Include the following dependencies in your app's build.gradle:

compile 'com.google.api-client:google-api-client:1.22.0'
compile 'com.google.api-client:google-api-client-android:1.22.0'
compile 'com.google.apis:google-api-services-people:v1-rev4-1.22.0'

Do an authorized GoogleSignIn like normal. It doesn't need any Scopes or Api's other than the basic account ones e.g.

GoogleSignInOptions.DEFAULT_SIGN_IN

.addApi(Auth.GOOGLE_SIGN_IN_API, gso)

and requests for email and profile is all you need.

Now, once you have a successful signin result, you can get the account, including the email (could maybe do this with the id too).

final GoogleSignInAccount acct = googleSignInResult.getSignInAccount();

Now the new part: Create and execute an AsyncTask to call the Google People API after you get the acct email.

// get Cover Photo Asynchronously
new GetCoverPhotoAsyncTask().execute(Prefs.getPersonEmail());

Here is the AsyncTask:

// Retrieve and save the url to the users Cover photo if they have one
private class GetCoverPhotoAsyncTask extends AsyncTask<String, Void, Void> {
    HttpTransport httpTransport = new NetHttpTransport();
    JacksonFactory jsonFactory = new JacksonFactory();

    // Retrieved from the sigin result of an authorized GoogleSignIn
    String personEmail;

    @Override
    protected Void doInBackground(String... params) {
        personEmail = params[0];
        Person userProfile = null;
        Collection<String> scopes = new ArrayList<>(Collections.singletonList(Scopes.PROFILE));

        GoogleAccountCredential credential =
                GoogleAccountCredential.usingOAuth2(SignInActivity.this, scopes);
        credential.setSelectedAccount(new Account(personEmail, "com.google"));

        People service = new People.Builder(httpTransport, jsonFactory, credential)
                .setApplicationName(getString(R.string.app_name)) // your app name
                .build();

        // Get info. on user
        try {
            userProfile = service.people().get("people/me").execute();
        } catch (IOException e) {
            Log.e(TAG, e.getMessage(), e);
        }

        // Get whatever you want
        if (userProfile != null) {
            List<CoverPhoto> covers = userProfile.getCoverPhotos();
            if (covers != null && covers.size() > 0) {
                CoverPhoto cover = covers.get(0);
                if (cover != null) {
                    // save url to cover photo here, load at will
                    //Prefs.setPersonCoverPhoto(cover.getUrl());
                }
            }
        }

        return null;
    }
}

Here is the stuff that is available from the Person

If you paste the code into your project, make sure the imports get resolved correctly. There are overlapping Class Names with some of the older API's.

After login, do:

 Plus.PeopleApi.load(mGoogleApiClient, acct.getId()).setResultCallback(new ResultCallback<People.LoadPeopleResult>() {
        @Override
        public void onResult(@NonNull People.LoadPeopleResult loadPeopleResult) {
            Person person = loadPeopleResult.getPersonBuffer().get(0);

            LogUtil.d("googleuser: getGivenName " + (person.getName().getGivenName()));
            LogUtil.d("googleuser: getFamilyName " + (person.getName().getFamilyName()));
            LogUtil.d("googleuser: getDisplayName " + (person.getDisplayName()));
            LogUtil.d("googleuser: getGender " + (person.getGender() + ""));
            LogUtil.d("googleuser: getBirthday " + (person.getBirthday() + ""));
        }
    });

UPDATE:

Since Plus.PeopleApi has been deprecated in Google Play services 9.4 as Google's declaration notes, please refer to the following solutions using Google People API instead:

Get person details in new google sign in Play Services 8.3 (Isabella Chen's answer);

Cannot get private birthday from Google Plus account although explicit request

END OF UPDATE

---

First of all, make sure you have created Google+ profile for your Google account. Then you can refer to the following code:

GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)             
                .requestScopes(new Scope(Scopes.PLUS_LOGIN))
                .requestEmail()
                .build();

and

mGoogleApiClient = new GoogleApiClient.Builder(this)
                .enableAutoManage(this /* FragmentActivity */, this /* OnConnectionFailedListener */)
                .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
                .addApi(Plus.API)
                .build();

Then

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

        // Result returned from launching the Intent from GoogleSignInApi.getSignInIntent(...);
        if (requestCode == RC_SIGN_IN) {
            GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
            handleSignInResult(result);

            // G+
            Person person  = Plus.PeopleApi.getCurrentPerson(mGoogleApiClient);
            Log.i(TAG, "--------------------------------");
            Log.i(TAG, "Display Name: " + person.getDisplayName());
            Log.i(TAG, "Gender: " + person.getGender());
            Log.i(TAG, "AboutMe: " + person.getAboutMe());
            Log.i(TAG, "Birthday: " + person.getBirthday());
            Log.i(TAG, "Current Location: " + person.getCurrentLocation());
            Log.i(TAG, "Language: " + person.getLanguage());
        }
    }

Inside build.gradle file

// Dependency for Google Sign-In
compile 'com.google.android.gms:play-services-auth:8.3.0'
compile 'com.google.android.gms:play-services-plus:8.3.0'

You can take a look at My GitHub sample project. Hope this helps!