AndroidでのTwitter統合の問題

Question

私は に従うこのlink AndroidでTwitterを統合するサイト。
しかし、私のアプリケーションを実行すると、が返ってくるので、問題は私のコンシューマキーと秘密です。アプリケーションが予期せず をエラーと私はlogcatで確認したときに、それは私のlogcat結果は

07-07 11:06:50.962: ERROR/AndroidRuntime(323): java.lang.RuntimeException: Unable to resume activity {com.ecs.android.sample.twitter/com.ecs.android.sample.twitter.AndroidTwitterSample}: java.lang.NullPointerException 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3128) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:3143) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2684) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.app.ActivityThread.access$2300(ActivityThread.java:125) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.os.Handler.dispatchMessage(Handler.java:99) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323): Caused by: java.lang.NullPointerException 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at com.ecs.android.sample.twitter.TwitterUtils.isAuthenticated(TwitterUtils.java:18) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at com.ecs.android.sample.twitter.AndroidTwitterSample.updateLoginStatus(AndroidTwitterSample.java:67) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at com.ecs.android.sample.twitter.AndroidTwitterSample.onResume(AndroidTwitterSample.java:63) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.app.Instrumentation.callActivityOnResume(Instrumentation.java:1149) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.app.Activity.performResume(Activity.java:3823) 
07-07 11:06:50.962: ERROR/AndroidRuntime(323):  at android.app.ActivityThread.performResumeActivity(ActivityThread.java:3118) 

あるnull pointer exception

を与えて停止している私が作っています間違いが何であるかを教えてください？

そして5クラスで全体のコードは次のとおりです。

定数 パッケージcom.ecs.android.sample.twitterをクラス - 。

package com.ecs.android.sample.twitter;

public class Constants { 

    public static final String CONSUMER_KEY = "consumer key"; 
    public static final String CONSUMER_SECRET= "consumer secret key"; 

    public static final String REQUEST_URL = "http://api.twitter.com/oauth/request_token"; 
    public static final String ACCESS_URL = "http://api.twitter.com/oauth/access_token"; 
    public static final String AUTHORIZE_URL = "http://api.twitter.com/oauth/authorize"; 

    public static final String CALLBACK_SCHEME = "x-oauthflow-twitter"; 
    public static final String CALLBACK_HOST = "callback"; 
    public static final String CALLBACK_URL = CALLBACK_SCHEME + "://" + CALLBACK_HOST; 
} 

AndroidTwitterSampleクラス -

public class AndroidTwitterSample extends Activity { 

    private SharedPreferences prefs; 
    private final Handler mTwitterHandler = new Handler(); 
    private TextView loginStatus; 

    final Runnable mUpdateTwitterNotification = new Runnable() { 
     public void run() { 
      Toast.makeText(getBaseContext(), "Tweet sent !", Toast.LENGTH_LONG).show(); 
     } 
    }; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 
     this.prefs = PreferenceManager.getDefaultSharedPreferences(this); 

     loginStatus = (TextView)findViewById(R.id.login_status); 
     Button tweet = (Button) findViewById(R.id.btn_tweet); 
     Button clearCredentials = (Button) findViewById(R.id.btn_clear_credentials); 

     tweet.setOnClickListener(new View.OnClickListener() { 
      public void onClick(View v) { 
       if (TwitterUtils.isAuthenticated(prefs)) { 
        sendTweet(); 
       } else { 
        Intent i = new Intent(getApplicationContext(), PrepareRequestTokenActivity.class); 
        i.putExtra("tweet_msg",getTweetMsg()); 
        startActivity(i); 
       } 
      } 
     }); 

     clearCredentials.setOnClickListener(new View.OnClickListener() { 
      public void onClick(View v) { 
       clearCredentials(); 
       updateLoginStatus(); 
      } 
     }); 
    } 

    @Override 
    protected void onResume() { 
     super.onResume(); 
     updateLoginStatus(); 
    } 

    public void updateLoginStatus() { 
     loginStatus.setText("Logged into Twitter : " + TwitterUtils.isAuthenticated(prefs)); 
    } 


    private String getTweetMsg() { 
     return "Tweeting from Android App at " + new Date().toLocaleString(); 
    } 

    public void sendTweet() { 
     Thread t = new Thread() { 
      @Override 
      public void run() { 

       try { 
        TwitterUtils.sendTweet(prefs,getTweetMsg()); 
        mTwitterHandler.post(mUpdateTwitterNotification); 
       } catch (Exception ex) { 
        ex.printStackTrace(); 
       } 
      } 

     }; 
     t.start(); 
    } 

    private void clearCredentials() { 
     SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this); 
     final Editor edit = prefs.edit(); 
     edit.remove(OAuth.OAUTH_TOKEN); 
     edit.remove(OAuth.OAUTH_TOKEN_SECRET); 
     edit.commit(); 
    } 
} 

TwitterのUtilsのクラス -

import oauth.signpost.OAuth; 
import twitter4j.Twitter; 
import twitter4j.TwitterFactory; 
import twitter4j.http.AccessToken; 
import android.content.SharedPreferences; 

public class TwitterUtils { 

    public static boolean isAuthenticated(SharedPreferences prefs) { 

     String token = prefs.getString(OAuth.OAUTH_TOKEN, ""); 
     String secret = prefs.getString(OAuth.OAUTH_TOKEN_SECRET, ""); 

     AccessToken a = new AccessToken(token,secret); 
     Twitter twitter = new TwitterFactory().getInstance(); 
     twitter.setOAuthConsumer(Constants.CONSUMER_KEY, Constants.CONSUMER_SECRET); 
     twitter.setOAuthAccessToken(a); 

     try { 
      twitter.getAccountSettings(); 
      return true; 
     } catch (Exception e) { 
      return false; 
     } 
    } 

    public static void sendTweet(SharedPreferences prefs,String msg) throws Exception { 
     String token = prefs.getString(OAuth.OAUTH_TOKEN, ""); 
     String secret = prefs.getString(OAuth.OAUTH_TOKEN_SECRET, ""); 

     AccessToken a = new AccessToken(token,secret); 
     Twitter twitter = new TwitterFactory().getInstance(); 
     twitter.setOAuthConsumer(Constants.CONSUMER_KEY, Constants.CONSUMER_SECRET); 
     twitter.setOAuthAccessToken(a); 
     twitter.updateStatus(msg); 
    } 
} 

OAuthRequestTokenクラス -

public class OAuthRequestTokenTask extends AsyncTask<Void, Void, Void> { 

    final String TAG = getClass().getName(); 
    private Context context; 
    private OAuthProvider provider; 
    private OAuthConsumer consumer; 


    public OAuthRequestTokenTask(Context context,OAuthConsumer consumer,OAuthProvider provider) { 
     this.context = context; 
     this.consumer = consumer; 
     this.provider = provider; 
    } 

    public OAuthRequestTokenTask(PrepareRequestTokenActivity context2, 
      CommonsHttpOAuthConsumer consumer2, 
      CommonsHttpOAuthProvider provider2) { 
     // TODO Auto-generated constructor stub 
    } 


    @Override 
    protected Void doInBackground(Void... params) { 

     try { 
      Log.i(TAG, "Retrieving request token from Google servers"); 
      final String url = provider.retrieveRequestToken(consumer, Constants.CALLBACK_URL); 
      Log.i(TAG, "Popping a browser with the authorize URL : " + url); 
      Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url)).setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP | 
         Intent.FLAG_ACTIVITY_NO_HISTORY | Intent.FLAG_FROM_BACKGROUND); 
      context.startActivity(intent); 
     } catch (Exception e) { 
      Log.e(TAG, "Error during OAUth retrieve request token", e); 
     } 

     return null; 
    } 
} 

PrepareRequestTokenActivityクラス -

public class OAuthRequestTokenTask extends AsyncTask<Void, Void, Void> { 

    final String TAG = getClass().getName(); 
    private Context context; 
    private OAuthProvider provider; 
    private OAuthConsumer consumer; 

    public OAuthRequestTokenTask(Context context,OAuthConsumer consumer,OAuthProvider provider) { 
     this.context = context; 
     this.consumer = consumer; 
     this.provider = provider; 
    } 

    public OAuthRequestTokenTask(PrepareRequestTokenActivity context2, 
      CommonsHttpOAuthConsumer consumer2, 
      CommonsHttpOAuthProvider provider2) { 
     // TODO Auto-generated constructor stub 
    } 


    @Override 
    protected Void doInBackground(Void... params) { 

     try { 
      Log.i(TAG, "Retrieving request token from Google servers"); 
      final String url = provider.retrieveRequestToken(consumer, Constants.CALLBACK_URL); 
      Log.i(TAG, "Popping a browser with the authorize URL : " + url); 
      Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url)).setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP | 
         Intent.FLAG_ACTIVITY_NO_HISTORY | Intent.FLAG_FROM_BACKGROUND); 
      context.startActivity(intent); 
     } catch (Exception e) { 
      Log.e(TAG, "Error during OAUth retrieve request token", e); 
     } 

     return null; 
    } 
} 

Answer 1

CONSUMER_KEY = "enter consumer key here"とCONSUMER_SECRET="enter consumer secret here"をConstantsクラスに入れる必要があります。そのためには、アプリケーションをTwitterに登録する必要があります。アプリを登録するには、https://dev.twitter.com/userにアクセスしてください。その後、それはあなたにそれらの鍵を与えるでしょう。