当我尝试将我的推文对象添加到我的模型中的arraylist时,我遇到了这个问题,但是我得到了一个NullPointerException。这发生在我的SearchTweetsTask类中。 只有当我用twitter api搜索推文时才会发生这种情况。获取时间表和内容非常有效,没有任何问题。但只有当我搜索推文时,我才得到这个例外。 我通过我的操作栏中的搜索视图搜索推文,该操作栏是在我的MainActivity中创建的。 我希望你能帮助我。
以下是一些代码:
protected String doInBackground(String... params)
{
meldingen = "";
String result = "";
String searchString = params[0];
String decoded = "";
try {
decoded = URLEncoder.encode(searchString, "UTF-8");
} catch (UnsupportedEncodingException e1) {
Log.d("URL ENCODER", "De Search query is niet goed ingelezen");
}
String url = "https://api.twitter.com/1.1/search/tweets.json?q=";
String searchURL = url + decoded + "&count=50";
try{
HttpGet get = new HttpGet(searchURL);
Authenticate.authentication(get);
ResponseHandler<String> handler = new BasicResponseHandler();
result = httpClient.execute(get, handler);
JSONObject json = new JSONObject(result);
JSONArray jArray = json.getJSONArray("statuses");
for (int i = 0; i < jArray.length(); i++)
{
JSONObject subObject = jArray.getJSONObject(i);
Tweet tweet = new Tweet (subObject);
publishProgress(tweet);
}
}
catch(HttpResponseException e)
{
//all the catch exceptions
....
}
//GETTING NULLER POINTER HERE
protected void onProgressUpdate(Tweet... tweets) {
for (Tweet tweet : tweets) {
model.addSearchTweets(tweet);
}
}
模特课:
private ArrayList<Tweet> searchTweets = new ArrayList<Tweet>();
public void addSearchTweets(Tweet tweet)
{
searchTweets.add(tweet);
}
MainActivity:
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.actions, menu);
MenuItem searchItem = menu.findItem(R.id.action_search);
final SearchView searchView = (SearchView) searchItem.getActionView();
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
if(null != searchManager )
{
searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
searchView.setOnQueryTextListener(new OnQueryTextListener() {
@Override
public boolean onQueryTextSubmit(String search) {
model.clearSearchTweets();
InputMethodManager imm = (InputMethodManager)getSystemService(Context.INPUT_METHOD_SERVICE);
imm.hideSoftInputFromWindow(searchView.getWindowToken(), 0);
Fragment newFragment = new UserSearchTweetsFragment();
FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.replace(R.id.frame_container, newFragment);
transaction.addToBackStack(null);
SearchTweetsTask searchTweets = new SearchTweetsTask(MainActivity.this);
searchTweets.execute(search);
transaction.commit();
return true;
}
@Override
public boolean onQueryTextChange(String search) {
return true;
}
});
}
searchView.setIconifiedByDefault(false);
return true;
07-14 17:18:25.048:E / AndroidRuntime(9135):致命异常:主要 07-14 17:18:25.048:E / AndroidRuntime(9135):处理:nl.timkatgert.tweettweet,PID:9135 07-14 17:18:25.048:E / AndroidRuntime(9135):java.lang.NullPointerException 07-14 17:18:25.048:E / AndroidRuntime(9135):at nl.timkatgert.tweettweet.tasks.SearchTweetsTask.onProgressUpdate(SearchTweetsTask.java:117) 07-14 17:18:25.048:E / AndroidRuntime(9135):at nl.timkatgert.tweettweet.tasks.SearchTweetsTask.onProgressUpdate(SearchTweetsTask.java:1) 07-14 17:18:25.048:E / AndroidRuntime(9135):在android.os.AsyncTask $ InternalHandler.handleMessage(AsyncTask.java:648) 07-14 17:18:25.048:E / AndroidRuntime(9135):在android.os.Handler.dispatchMessage(Handler.java:102) 07-14 17:18:25.048:E / AndroidRuntime(9135):在android.os.Looper.loop(Looper.java:157) 07-14 17:18:25.048:E / AndroidRuntime(9135):在android.app.ActivityThread.main(ActivityThread.java:5356) 07-14 17:18:25.048:E / AndroidRuntime(9135):at java.lang.reflect.Method.invokeNative(Native Method) 07-14 17:18:25.048:E / AndroidRuntime(9135):at java.lang.reflect.Method.invoke(Method.java:515) 07-14 17:18:25.048:E / AndroidRuntime(9135):at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:1265) 07-14 17:18:25.048:E / AndroidRuntime(9135):at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081) 07-14 17:18:25.048:E / AndroidRuntime(9135):at dalvik.system.NativeStart.main(Native Method)