Wie Sie auf die neue Gmail-API von meine Android-app?

Ich versuche Zugriff auf die neue Gmail-API (angekündigt 25.06.2014) von meinem Android app, um wieder alle e-mail-Nachrichten in einem bestimmten Benutzer-account. Ich entwickle die app in Eclipse mit dem ADT-plug-in.

Was ich bisher getan habe:

• Registrierte ich die Anwendung in die Google Entwickler-Konsole
  
  (link: console.developers.google.com/project).

• Implementierte ich die Google+ Sign-in button (link: developers.google.com/+/mobile/android/sign-in).
  Die Google+ Sign-In-button wird der Benutzer authentifiziert und verwaltet die OAuth-2.0-Strömung, die vereinfacht die integration mit den Google-APIs.

• Ich einen zusätzlichen Anwendungsbereich "https://www.googleapis.com/auth/gmail.readonly' auf der Google+ - Autorisierung für den Zugriff auf die Gmail-API " angegeben
  (Link: developers.google.com/gmail/api/v1/reference/users/threads/list).

In diesem Punkt habe ich eine initialisierte GoogleApiClient Objekt.

Den GoogleApiClient Objekt umschließt eine ServiceConnection (link: developer.android.com/reference/android/content/ServiceConnection.html) an den Google Play services. Die GoogleApiClient-Objekt wird verwendet, um die Kommunikation mit der Google+ API und wird funktional nach dem asynchronen Verbindung mit dem service, der anzeigt, dass:

• Google Play services auf dem Gerät ausgeführt wird und die app-Aktivität wurde erfolgreich gebunden die service-Verbindung,
• der Benutzer ausgewählt hat, ein Konto, das Sie verwenden möchten, mit der app und
• dem Konto des Nutzers erteilt hat, die Berechtigungen, die die app anfordert.

Wie gehe ich vor, von hier zu bekommen alle Meldungen mit diesem httprequest?
Ich habe versucht, den Zugriff auf die Gmail-API an dieser Stelle, aber ich erhalte Authentifizierung error 401: Anmeldung erforderlich, sogar dachte, dass der Google+ login war erfolgreich, und ich habe Sie erfolgreich zurückgegeben wird eine Liste von Benutzer-Kreisen.

BEARBEITEN: SecondActivity.java

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

import com.google.android.gms.auth.GoogleAuthException;
import com.google.android.gms.auth.GoogleAuthUtil;
import com.google.android.gms.auth.GooglePlayServicesAvailabilityException;
import com.google.android.gms.auth.UserRecoverableAuthException;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
import com.google.android.gms.common.SignInButton;
import com.google.android.gms.common.api.CommonStatusCodes;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.GoogleApiClient.ConnectionCallbacks;
import com.google.android.gms.common.api.GoogleApiClient.OnConnectionFailedListener;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Scope;
import com.google.android.gms.plus.People;
import com.google.android.gms.plus.People.LoadPeopleResult;
import com.google.android.gms.plus.Plus;
import com.google.android.gms.plus.model.people.Person;
import com.google.android.gms.plus.model.people.PersonBuffer;
import com.google.api.services.gmail.Gmail;
import com.google.api.services.gmail.Gmail.Users;
import com.google.api.services.gmail.Gmail.Users.Messages.GmailImport;
import com.google.api.services.gmail.GmailRequest;
import com.google.api.services.gmail.GmailRequestInitializer;
import com.google.api.services.gmail.GmailScopes;

import android.app.AlertDialog;
import android.app.Dialog;
import android.app.PendingIntent;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentSender.SendIntentException;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v7.app.ActionBarActivity;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import mk.ukim.feit.recognizer.application.PeopleAdapter;
import mk.ukim.feit.recognizer.interfaces.GetMessages;
import mk.ukim.feit.recognizer.tasks.GetMessagesTask;
import mk.ukim.feit.recognizer.util.MyClass;
import mk.ukim.feit.recognizer.util.exception.FaceClientException;
import mk.ukim.feit.recognizer.util.model.Face;
import mk.ukim.feit.recognizer.util.model.Guess;
import mk.ukim.feit.recognizer.util.model.Photo;
import mk.ukim.feit.recognizer.util.response.PhotoResponse;
import mk.ukim.feit.recognizer.util.response.PhotoResponseImpl;

import java.io.IOException;
import java.util.ArrayList;


public class SecondActivity extends FragmentActivity implements
    GetMessages, ConnectionCallbacks, OnConnectionFailedListener,
    ResultCallback<People.LoadPeopleResult>, View.OnClickListener {

  private static final String TAG = "android-plus-quickstart";

  private static final int STATE_DEFAULT = 0;
  private static final int STATE_SIGN_IN = 1;
  private static final int STATE_IN_PROGRESS = 2;

  private static final int RC_SIGN_IN = 0;
  private static final int MY_ACTIVITYS_AUTH_REQUEST_CODE=045;

  private static final int DIALOG_PLAY_SERVICES_ERROR = 0;

  private static final String SAVED_PROGRESS = "sign_in_progress";

  private GoogleApiClient mGoogleApiClient;
  String name; 

  private PendingIntent mSignInIntent;
  private int mSignInError;
  private SignInButton mSignInButton;
  private Button mSignOutButton;
  private Button mRevokeButton;
  private TextView mStatus;
  private ListView mCirclesListView;
  private ArrayAdapter<String> mCirclesAdapter;
  private ArrayList<String> mCirclesList;

  public Scope gmail=new Scope("https://www.googleapis.com/auth/gmail.readonly");
  String scope="https://www.googleapis.com/auth/gmail.readonly";
  String email="[email protected]";



@Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_second);

    Intent intent = getIntent();
    name="Team";

    mSignInButton = (SignInButton) findViewById(R.id.sign_in_button);
    mSignOutButton = (Button) findViewById(R.id.sign_out_button);
    mRevokeButton = (Button) findViewById(R.id.revoke_access_button);
    mStatus = (TextView) findViewById(R.id.sign_in_status);
    mCirclesListView = (ListView) findViewById(R.id.circles_list);

    mSignInButton.setOnClickListener(this);
    mSignOutButton.setOnClickListener(this);
    mRevokeButton.setOnClickListener(this);

    mCirclesList = new ArrayList<String>();
    mCirclesAdapter = new ArrayAdapter<String>(
        this, R.layout.circle_member, mCirclesList);
    mCirclesListView.setAdapter(mCirclesAdapter);

    if (savedInstanceState != null) {
      mSignInProgress = savedInstanceState
          .getInt(SAVED_PROGRESS, STATE_DEFAULT);

    }

    mGoogleApiClient = buildGoogleApiClient();
  }



private GoogleApiClient buildGoogleApiClient() {
    return new GoogleApiClient.Builder(this)
        .addConnectionCallbacks(this)
        .addOnConnectionFailedListener(this)
        .addApi(Plus.API, Plus.PlusOptions.builder().build())
        .addScope(Plus.SCOPE_PLUS_LOGIN)
        .addScope(gmail)
        .build();
  }

@Override
  protected void onStart() {
    super.onStart();
    mGoogleApiClient.connect();
    getAndUseAuthTokenInAsyncTask();
  }



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

    if (mGoogleApiClient.isConnected()) {
      mGoogleApiClient.disconnect();
    }
  }

  @Override
  protected void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    outState.putInt(SAVED_PROGRESS, mSignInProgress);
  }



@Override
  public void onClick(View v) {
    if (!mGoogleApiClient.isConnecting()) {
          switch (v.getId()) {
          case R.id.sign_in_button:
            mStatus.setText(R.string.status_signing_in);
            resolveSignInError();
            break;
          case R.id.sign_out_button:
            Plus.AccountApi.clearDefaultAccount(mGoogleApiClient);
            mGoogleApiClient.disconnect();
            mGoogleApiClient.connect();
            break;
          case R.id.revoke_access_button:
            Plus.AccountApi.clearDefaultAccount(mGoogleApiClient);
            Plus.AccountApi.revokeAccessAndDisconnect(mGoogleApiClient);
            mGoogleApiClient = buildGoogleApiClient();
            mGoogleApiClient.connect();
            break;
      }
    }
  }

  @Override
  public void onConnected(Bundle connectionHint) {
    Log.i(TAG, "onConnected");

    getAndUseAuthTokenInAsyncTask();

    mSignInButton.setEnabled(false);
    mSignOutButton.setEnabled(true);
    mRevokeButton.setEnabled(true);

    //Retrieve some profile information. This is OK
    Person currentUser = Plus.PeopleApi.getCurrentPerson(mGoogleApiClient);
    String klient=mGoogleApiClient.toString();


    mStatus.setText(String.format(
        getResources().getString(R.string.signed_in_as),
        currentUser.getDisplayName()));


    Plus.PeopleApi.loadVisible(mGoogleApiClient, null)
        .setResultCallback(this);

    GetMessagesTask task = new GetMessagesTask(
            SecondActivity.this, name, mGoogleApiClient);
        task.setDelegate(SecondActivity.this);
        task.execute();

    //Indicate that the sign in process is complete.
    mSignInProgress = STATE_DEFAULT;

  }

  @Override
  public void onConnectionFailed(ConnectionResult result) {
    //Refer to the javadoc for ConnectionResult to see what error codes might
    //be returned in onConnectionFailed.
    Log.i(TAG, "onConnectionFailed: ConnectionResult.getErrorCode() = "
        + result.getErrorCode());

    if (mSignInProgress != STATE_IN_PROGRESS) {
      mSignInIntent = result.getResolution();
      mSignInError = result.getErrorCode();

      if (mSignInProgress == STATE_SIGN_IN) {
        //STATE_SIGN_IN indicates the user already clicked the sign in button
        //so we should continue processing errors until the user is signed in
        //or they click cancel.
        resolveSignInError();
      }
    }

    onSignedOut();
  }


  private void resolveSignInError() {
    if (mSignInIntent != null) {

      try {
        mSignInProgress = STATE_IN_PROGRESS;
        startIntentSenderForResult(mSignInIntent.getIntentSender(),
            RC_SIGN_IN, null, 0, 0, 0);
      } catch (SendIntentException e) {
        Log.i(TAG, "Sign in intent could not be sent: "
            + e.getLocalizedMessage());
        //The intent was canceled before it was sent.  Attempt to connect to
        //get an updated ConnectionResult.
        mSignInProgress = STATE_SIGN_IN;
        mGoogleApiClient.connect();

      }
    } else {
      //Google Play services wasn't able to provide an intent for some
      //error types, so we show the default Google Play services error
      //dialog which may still start an intent if the
      //user can resolve the issue.
      showDialog(DIALOG_PLAY_SERVICES_ERROR);
    }
  }


  @Override
  public void onResult(LoadPeopleResult peopleData) {
    if (peopleData.getStatus().getStatusCode() == CommonStatusCodes.SUCCESS) {
      mCirclesList.clear();
      PersonBuffer personBuffer = peopleData.getPersonBuffer();
      try {
          int count = personBuffer.getCount();
          for (int i = 0; i < count; i++) {
              mCirclesList.add(personBuffer.get(i).getDisplayName());
          }
      } finally {
          personBuffer.close();
      }

      mCirclesAdapter.notifyDataSetChanged();
    } else {
      Log.e(TAG, "Error requesting visible circles: " + peopleData.getStatus());
    }
  }

  private void onSignedOut() {
    //Update the UI to reflect that the user is signed out.
    mSignInButton.setEnabled(true);
    mSignOutButton.setEnabled(false);
    mRevokeButton.setEnabled(false);

    mStatus.setText(R.string.status_signed_out);

    mCirclesList.clear();
    mCirclesAdapter.notifyDataSetChanged();
  }

  @Override
  public void onConnectionSuspended(int cause) {
    //The connection to Google Play services was lost for some reason.
    //We call connect() to attempt to re-establish the connection or get a
    //ConnectionResult that we can attempt to resolve.
    mGoogleApiClient.connect();
  }

  @Override
  protected Dialog onCreateDialog(int id) {
    switch(id) {
      case DIALOG_PLAY_SERVICES_ERROR:
        if (GooglePlayServicesUtil.isUserRecoverableError(mSignInError)) {
          return GooglePlayServicesUtil.getErrorDialog(
              mSignInError,
              this,
              RC_SIGN_IN,
              new DialogInterface.OnCancelListener() {
                @Override
                public void onCancel(DialogInterface dialog) {
                  Log.e(TAG, "Google Play services resolution cancelled");
                  mSignInProgress = STATE_DEFAULT;
                  mStatus.setText(R.string.status_signed_out);
                }
              });
        } else {
          return new AlertDialog.Builder(this)
              .setMessage(R.string.play_services_error)
              .setPositiveButton(R.string.close,
                  new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                      Log.e(TAG, "Google Play services error could not be "
                          + "resolved: " + mSignInError);
                      mSignInProgress = STATE_DEFAULT;
                      mStatus.setText(R.string.status_signed_out);
                    }
                  }).create();
        }
      default:
        return super.onCreateDialog(id);
    }
  }




    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
           if (requestCode == MY_ACTIVITYS_AUTH_REQUEST_CODE) {
               if (resultCode == RESULT_OK) {
                   getAndUseAuthTokenInAsyncTask();
               }
           }
       }


       public void getAndUseAuthTokenBlocking() throws UserRecoverableAuthException, IOException, GoogleAuthException {

              final String token = GoogleAuthUtil.getToken(this, email, scope);
              String fff="";
        }      


       public void getAndUseAuthTokenInAsyncTask() {

        AsyncTask<Void, Void, Void> task = new AsyncTask<Void,Void, Void>() {


               @Override
               protected Void doInBackground(Void... params) {
                   //TODO Auto-generated method stub
                   try {
                    getAndUseAuthTokenBlocking();
                } catch (UserRecoverableAuthException e) {
                    //TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (IOException e) {
                    //TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (GoogleAuthException e) {
                    //TODO Auto-generated catch block
                    e.printStackTrace();
                }
                   return null;
               }
           };
           task.execute((Void)null);
       }

    }

EDIT 2: LogCat

07-16 06:44:27.300: E/AndroidRuntime(11875): FATAL EXCEPTION: AsyncTask #2
07-16 06:44:27.300: E/AndroidRuntime(11875): java.lang.RuntimeException: An error occured while executing doInBackground()
07-16 06:44:27.300: E/AndroidRuntime(11875):    at android.os.AsyncTask$3.done(AsyncTask.java:299)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at java.util.concurrent.FutureTask.run(FutureTask.java:137)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at java.lang.Thread.run(Thread.java:856)
07-16 06:44:27.300: E/AndroidRuntime(11875): Caused by: java.lang.NoClassDefFoundError: com.google.api.client.googleapis.auth.oauth2.GoogleCredential
07-16 06:44:27.300: E/AndroidRuntime(11875):    at mk.ukim.feit.recognizer.GmailLinkGrabberService$getAuthToken.doInBackground(GmailLinkGrabberService.java:104)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at mk.ukim.feit.recognizer.GmailLinkGrabberService$getAuthToken.doInBackground(GmailLinkGrabberService.java:1)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at android.os.AsyncTask$2.call(AsyncTask.java:287)
07-16 06:44:27.300: E/AndroidRuntime(11875):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
07-16 06:44:27.300: E/AndroidRuntime(11875):    ... 5 more