Java 在android中使用twitter4j显示twitter提要时，应用程序停止

我正在做我的android项目，遇到了这个运行时错误：不幸的是，Example2已经停止。我只想使用twitter4j twitter4j-core-3.0.3.jar显示twitter提要，但这段代码有一个例外：

tweets = mTwitter.search(new Query(queryString)).getTweets();

我用java应用程序在NetBean上对此进行了测试，结果非常好。所有的twitter都会显示出来，我认为用户身份验证没有问题。我尝试遵循本教程：

它似乎对某些人有效，但对我无效：

代码如下：

公共类MainActivity扩展了活动 {

---

非常感谢您的反馈！

我不了解流程，但在showTweetsAbout之前是否调用了onPostExecute？如果不是，那么您的变量mTwitter将为null，因此NPEI对流程不太确定。实际上，我在Android中是个新手。我使用AsyncTask是因为之前遇到了一个错误，即NetworkMainThread Ex异常。断点会有帮助，并在调用方法之前尝试查看你的mTwitter是否为null-这解释了你反馈的全部内容。我编辑了代码，没有null异常，但现在我发现了另一个问题：它仍然在这部分：tweets=mTwitter.searchnew QueryqueryString.getTweets。它有什么问题吗安卓版怎么办？我知道了。我不应该在不同的线程上访问UI。谢谢！

Context mContext;
Twitter mTwitter;
ListView mListView;

private static final String TWITTER_CONSUMER_KEY = "xx";
private static final String TWITTER_SECRET_KEY = "xxx";
private static final String TWITTER_ACCESS_TOKEN = "xx";
private static final String TWITTER_ACCESS_TOKEN_SECRET = "xx";

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mListView = (ListView) findViewById(R.id.listview);
    mContext = getApplicationContext();
    mTwitter = getTwitter();

}


protected  void onResume()
{
    super.onResume();
     new AsyncTask<Void,Void,Void>(){

         protected Void doInBackground(Void... args){
            showTweetsAbout("happy"); 
             return null;
         }

     }.execute(); 

}
private Twitter getTwitter() {
    ConfigurationBuilder cb = new ConfigurationBuilder();     
    cb.setDebugEnabled(true);
    cb.setOAuthConsumerKey(TWITTER_CONSUMER_KEY);
    cb.setOAuthConsumerSecret(TWITTER_SECRET_KEY);
    cb.setOAuthAccessToken(TWITTER_ACCESS_TOKEN);
    cb.setOAuthAccessTokenSecret(TWITTER_ACCESS_TOKEN_SECRET);

    return new TwitterFactory(cb.build()).getInstance();
}

private void showTweetsAbout(String queryString) {
    List<Status> tweets = new ArrayList<Status>();
    ArrayList<String> tweetTexts = new ArrayList<String>();

   try {
       tweets = mTwitter.search(new Query(queryString)).getTweets()//if I comment this line, the code works fine

       // for (Status t : tweets) {
            tweetTexts.add("asdadsadasd\n\n");
        //}
    } catch (Exception e) {
        tweetTexts.add("Twitter query failed: " + e.toString());
    }
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
            android.R.layout.simple_list_item_1, android.R.id.text1, tweetTexts);
    mListView.setAdapter(adapter);
}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.example2"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.example2.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>    
        </activity>
    </application>

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.INTERNET" />

</manifest>

07-01 07:39:24.113: E/AndroidRuntime(3979):     at android.view.View.setFlags(View.java:8412)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at android.view.View.setFocusableInTouchMode(View.java:5790)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at android.widget.AdapterView.checkFocus(AdapterView.java:717)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at android.widget.ListView.setAdapter(ListView.java:463)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at com.example.example2.MainActivity.showTweetsAbout(MainActivity.java:94)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at com.example.example2.MainActivity.access$0(MainActivity.java:78)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at com.example.example2.MainActivity$1.doInBackground(MainActivity.java:52)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at com.example.example2.MainActivity$1.doInBackground(MainActivity.java:1)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at android.os.AsyncTask$2.call(AsyncTask.java:287)
07-01 07:39:24.113: E/AndroidRuntime(3979):     at java.util.concurrent.FutureTask.run(FutureTask.java:234)
07-01 07:39:24.113: E/AndroidRuntime(3979):     ... 4 more
07-01 07:42:19.853: E/AndroidRuntime(4049): FATAL EXCEPTION: AsyncTask #1
07-01 07:42:19.853: E/AndroidRuntime(4049): java.lang.RuntimeException: An error occured while executing doInBackground()
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.os.AsyncTask$3.done(AsyncTask.java:299)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at java.util.concurrent.FutureTask.run(FutureTask.java:239)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at java.lang.Thread.run(Thread.java:856)
07-01 07:42:19.853: E/AndroidRuntime(4049): Caused by: android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:4746)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.view.ViewRootImpl.focusableViewAvailable(ViewRootImpl.java:2588)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:608)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:608)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:608)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.view.ViewGroup.focusableViewAvailable(ViewGroup.java:608)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.view.View.setFlags(View.java:8412)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.view.View.setFocusableInTouchMode(View.java:5790)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.widget.AdapterView.checkFocus(AdapterView.java:717)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.widget.ListView.setAdapter(ListView.java:463)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at com.example.example2.MainActivity.showTweetsAbout(MainActivity.java:94)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at com.example.example2.MainActivity.access$0(MainActivity.java:78)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at com.example.example2.MainActivity$1.doInBackground(MainActivity.java:52)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at com.example.example2.MainActivity$1.doInBackground(MainActivity.java:1)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at android.os.AsyncTask$2.call(AsyncTask.java:287)
07-01 07:42:19.853: E/AndroidRuntime(4049):     at java.util.concurrent.FutureTask.run(FutureTask.java:234)
07-01 07:42:19.853: E/AndroidRuntime(4049):     ... 4 more