“Calling this from your main thread can lead to deadlock and/or ANRs while getting accesToken” from GoogleAuthUtil(Google Plus integration in Android)

Try it with an AsyncTask like this:

        AsyncTask<Void, Void, String> task = new AsyncTask<Void, Void, String>() {
            @Override
            protected String doInBackground(Void... params) {
                String token = null;

                try {
                    token = GoogleAuthUtil.getToken(
                            MainActivity.this,
                            mGoogleApiClient.getAccountName(),
                            "oauth2:" + SCOPES);
                } catch (IOException transientEx) {
                    // Network or server error, try later
                    Log.e(TAG, transientEx.toString());
                } catch (UserRecoverableAuthException e) {
                    // Recover (with e.getIntent())
                    Log.e(TAG, e.toString());
                    Intent recover = e.getIntent();
                    startActivityForResult(recover, REQUEST_CODE_TOKEN_AUTH);
                } catch (GoogleAuthException authEx) {
                    // The call is not ever expected to succeed
                    // assuming you have already verified that 
                    // Google Play services is installed.
                    Log.e(TAG, authEx.toString());
                }

                return token;
            }

            @Override
            protected void onPostExecute(String token) {
                Log.i(TAG, "Access token retrieved:" + token);
            }

        };
        task.execute();

SCOPES is a space separated list of OAuth 2.0 scope strings. For example SCOPES could be defined as:

public static final String SCOPES = "https://www.googleapis.com/auth/plus.login "
    + "https://www.googleapis.com/auth/drive.file";

These represent the permissions that your app is requesting from the user. The scopes requested in this example are documented here:

• https://developers.google.com/+/api/oauth
• https://developers.google.com/drive/android/files