Создание приложения, которое интегрирует Twitter. Я использую этот урок:

http://blog.blundell-apps.com/sending-a-tweet/

package com.blundell.tut.ttt;

import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.webkit.WebView;
import android.widget.Button;
import android.widget.Toast;
import twitter4j.Twitter;
import twitter4j.TwitterException;
import twitter4j.TwitterFactory;
import twitter4j.auth.AccessToken;
import twitter4j.auth.RequestToken;

public class TweetToTwitterActivity extends Activity {

    private static final String TAG = "Blundell.TweetToTwitterActivity";

    /** Name to store the users access token */
    private static final String PREF_ACCESS_TOKEN = "accessToken";
    /** Name to store the users access token secret */
    private static final String PREF_ACCESS_TOKEN_SECRET = "accessTokenSecret";
    /** Consumer Key generated when you registered your app at https://dev.twitter.com/apps/ */
    private static final String CONSUMER_KEY = "yourConsumerKey";
    /** Consumer Secret generated when you registered your app at https://dev.twitter.com/apps/  */
    private static final String CONSUMER_SECRET = "yourConsumerSecret"; // XXX Encode in your app
    /** The url that Twitter will redirect to after a user log's in - this will be picked up by your app manifest and redirected into this activity */
    private static final String CALLBACK_URL = "tweet-to-twitter-blundell-01-android:///";
    /** Preferences to store a logged in users credentials */
    private SharedPreferences mPrefs;
    /** Twitter4j object */
    private Twitter mTwitter;
    /** The request token signifies the unique ID of the request you are sending to twitter  */
    private RequestToken mReqToken;

    private Button mLoginButton;
    private Button mTweetButton;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Log.i(TAG, "Loading TweetToTwitterActivity");
        setContentView(R.layout.activity_main);

        // Create a new shared preference object to remember if the user has
        // already given us permission
        mPrefs = getSharedPreferences("twitterPrefs", MODE_PRIVATE);
        Log.i(TAG, "Got Preferences");

        // Load the twitter4j helper
        mTwitter = new TwitterFactory().getInstance();
        Log.i(TAG, "Got Twitter4j");

        // Tell twitter4j that we want to use it with our app
        mTwitter.setOAuthConsumer(CONSUMER_KEY, CONSUMER_SECRET);
        Log.i(TAG, "Inflated Twitter4j");

        mLoginButton = (Button) findViewById(R.id.login_button);
        mTweetButton = (Button) findViewById(R.id.tweet_button);
    }

    /**
     * Button clickables are declared in XML as this projects min SDK is 1.6<br> <br> 
     * Checks if the user has given this app permission to use twitter
     * before<br> If so login and enable tweeting<br> 
     * Otherwise redirect to Twitter for permission
     * 
     * @param v the clicked button
     */
    public void buttonLogin(View v) {
        Log.i(TAG, "Login Pressed");
        if (mPrefs.contains(PREF_ACCESS_TOKEN)) {
            Log.i(TAG, "Repeat User");
            loginAuthorisedUser();
        } else {
            Log.i(TAG, "New User");
            loginNewUser();
        }
    }

    /**
     * Button clickables are declared in XML as this projects min SDK is 1.6<br> <br>
     * 
     * @param v the clicked button
     */
    public void buttonTweet(View v) {
        Log.i(TAG, "Tweet Pressed");
        tweetMessage();
    }

    /**
     * Create a request that is sent to Twitter asking 'can our app have permission to use Twitter for this user'<br> 
     * We are given back the {@link mReqToken}
     * that is a unique indetifier to this request<br> 
     * The browser then pops up on the twitter website and the user logins in ( we never see this informaton
     * )<br> Twitter then redirects us to {@link CALLBACK_URL} if the login was a success<br>
     * 
     */
    private void loginNewUser() {
        try {
            Log.i(TAG, "Request App Authentication");
            mReqToken = mTwitter.getOAuthRequestToken(CALLBACK_URL);

            Log.i(TAG, "Starting Webview to login to twitter");
            WebView twitterSite = new WebView(this);
            twitterSite.loadUrl(mReqToken.getAuthenticationURL());
            setContentView(twitterSite);

        } catch (TwitterException e) {
            Toast.makeText(this, "Twitter Login error, try again later", Toast.LENGTH_SHORT).show();
        }
    }

    /**
     * The user had previously given our app permission to use Twitter<br> 
     * Therefore we retrieve these credentials and fill out the Twitter4j helper
     */
    private void loginAuthorisedUser() {
        String token = mPrefs.getString(PREF_ACCESS_TOKEN, null);
        String secret = mPrefs.getString(PREF_ACCESS_TOKEN_SECRET, null);

        // Create the twitter access token from the credentials we got previously
        AccessToken at = new AccessToken(token, secret);

        mTwitter.setOAuthAccessToken(at);

        Toast.makeText(this, "Welcome back", Toast.LENGTH_SHORT).show();

        enableTweetButton();
    }

    /**
     * Catch when Twitter redirects back to our {@link CALLBACK_URL}<br> 
     * We use onNewIntent as in our manifest we have singleInstance="true" if we did not the
     * getOAuthAccessToken() call would fail
     */
    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        Log.i(TAG, "New Intent Arrived");
        dealWithTwitterResponse(intent);
    }

    @Override
    protected void onResume() {
        super.onResume();
        Log.i(TAG, "Arrived at onResume");
    }

    /**
     * Twitter has sent us back into our app<br> 
     * Within the intent it set back we have a 'key' we can use to authenticate the user
     * 
     * @param intent
     */
    private void dealWithTwitterResponse(Intent intent) {
        Uri uri = intent.getData();
        if (uri != null && uri.toString().startsWith(CALLBACK_URL)) { // If the user has just logged in
            String oauthVerifier = uri.getQueryParameter("oauth_verifier");

            authoriseNewUser(oauthVerifier);
        }
    }

    /**
     * Create an access token for this new user<br> 
     * Fill out the Twitter4j helper<br> 
     * And save these credentials so we can log the user straight in next time
     * 
     * @param oauthVerifier
     */
    private void authoriseNewUser(String oauthVerifier) {
        try {
            AccessToken at = mTwitter.getOAuthAccessToken(mReqToken, oauthVerifier);
            mTwitter.setOAuthAccessToken(at);

            saveAccessToken(at);

            // Set the content view back after we changed to a webview
            setContentView(R.layout.activity_main);

            enableTweetButton();
        } catch (TwitterException e) {
            Toast.makeText(this, "Twitter auth error x01, try again later", Toast.LENGTH_SHORT).show();
        }
    }

    /**
     * Allow the user to Tweet
     */
    private void enableTweetButton() {
        Log.i(TAG, "User logged in - allowing to tweet");
        mLoginButton.setEnabled(false);
        mTweetButton.setEnabled(true);
    }

    /**
     * Send a tweet on your timeline, with a Toast msg for success or failure
     */
    private void tweetMessage() {
        try {
            mTwitter.updateStatus("Test - Tweeting with @Blundell_apps #AndroidDev Tutorial using #Twitter4j http://blog.blundell-apps.com/sending-a-tweet/");

            Toast.makeText(this, "Tweet Successful!", Toast.LENGTH_SHORT).show();
        } catch (TwitterException e) {
            Toast.makeText(this, "Tweet error, try again later", Toast.LENGTH_SHORT).show();
        }
    }

    private void saveAccessToken(AccessToken at) {
        String token = at.getToken();
        String secret = at.getTokenSecret();
        Editor editor = mPrefs.edit();
        editor.putString(PREF_ACCESS_TOKEN, token);
        editor.putString(PREF_ACCESS_TOKEN_SECRET, secret);
        editor.commit();
    }
}

здесь код, написанный в методе onNewIntent (), не работает. Я устанавливаю только setcontentView, что это за проблема?

и это манифест