Почему данные не получены

Question

Я хотел бы получить данные от http://api.eventful.com/rest/events/search?app_key=42t54cX7RbrDFczc&location=singapore. Тег под заголовками "start_time", "longitude", "latitude". Но я не уверен, почему это невозможно было отобразить после того, как я добавил долготу и широту.

Это из LogCat:

08-07 17:17:44.190: E/AndroidRuntime(23734): FATAL EXCEPTION: main 
08-07 17:17:44.190: E/AndroidRuntime(23734): java.lang.NullPointerException 
08-07 17:17:44.190: E/AndroidRuntime(23734): at com.example.eventfulmaptry.MainActivity$ItemAdapter.getView(MainActivity.java:147) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.AbsListView.obtainView(AbsListView.java:1618) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.ListView.measureHeightOfChildren(ListView.java:1241) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.ListView.onMeasure(ListView.java:1152) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.View.measure(View.java:8513) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3143) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.LinearLayout.measureVertical(LinearLayout.java:386) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.View.measure(View.java:8513) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3143) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.View.measure(View.java:8513) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.LinearLayout.measureVertical(LinearLayout.java:531) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.View.measure(View.java:8513) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3143) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.View.measure(View.java:8513) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.ViewRoot.performTraversals(ViewRoot.java:857) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.view.ViewRoot.handleMessage(ViewRoot.java:1878) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.os.Handler.dispatchMessage(Handler.java:99) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.os.Looper.loop(Looper.java:130) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at android.app.ActivityThread.main(ActivityThread.java:3691) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at java.lang.reflect.Method.invokeNative(Native Method) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at java.lang.reflect.Method.invoke(Method.java:507) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:912) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:670) 
08-07 17:17:44.190: E/AndroidRuntime(23734): at dalvik.system.NativeStart.main(Native Method) 

Это мой код:

public class MainActivity extends Activity { 

    ArrayList<String> title; 
    ArrayList<String> start_time; 
    ArrayList<String> latitude; 
    ArrayList<String> longitude; 

    ItemAdapter adapter1; 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 

     ListView list = (ListView) findViewById(R.id.list); 
     title = new ArrayList<String>(); 
     latitude = new ArrayList<String>(); 
     longitude = new ArrayList<String>(); 
     try { 

      URL url = new URL(
        "http://api.eventful.com/rest/events/search?app_key=42t54cX7RbrDFczc&location=singapore"); 
      DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); 
      DocumentBuilder db = dbf.newDocumentBuilder(); 
      Document doc = db.parse(new InputSource(url.openStream())); 
      doc.getDocumentElement().normalize(); 

      NodeList nodeList = doc.getElementsByTagName("event"); 
      for (int i = 0; i < nodeList.getLength(); i++) { 

       Node node = nodeList.item(i);  

       Element fstElmnt = (Element) node; 

       NodeList nameList = fstElmnt.getElementsByTagName("title"); 
       Element nameElement = (Element) nameList.item(0); 
       nameList = nameElement.getChildNodes();   
       title.add(""+ ((Node) nameList.item(0)).getNodeValue()); 

       NodeList websiteList = fstElmnt.getElementsByTagName("start_time"); 
       Element websiteElement = (Element) websiteList.item(0); 
       websiteList = websiteElement.getChildNodes(); 
       start_time.add(""+ ((Node) websiteList.item(0)).getNodeValue());   

       NodeList websiteList1 = fstElmnt.getElementsByTagName("latitude"); 
       Element websiteElement1 = (Element) websiteList1.item(0); 
       websiteList1 = websiteElement1.getChildNodes(); 
       latitude.add(""+ ((Node) websiteList1.item(0)).getNodeValue());   


       NodeList websiteList2 = fstElmnt.getElementsByTagName("longitude"); 
       Element websiteElement2 = (Element) websiteList2.item(0); 
       websiteList2 = websiteElement2.getChildNodes(); 
       longitude.add(""+ ((Node) websiteList2.item(0)).getNodeValue()); 




      } 
     } catch (Exception e) { 
      System.out.println("XML Pasing Excpetion = " + e); 
     } 

     adapter1 = new ItemAdapter(this); 
     list.setAdapter(adapter1); 
    } 


    class ItemAdapter extends BaseAdapter { 

     final LayoutInflater mInflater; 

     private class ViewHolder { 
      public TextView title_text; 
      public TextView des_text; 
      public TextView lat_text; 
      public TextView long_text; 


     } 

     public ItemAdapter(Context context) { 
      // TODO Auto-generated constructor stub 
      super(); 
      mInflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);  
     } 

     //@Override 
     public int getCount() { 
      return title.size(); 
     } 

     //@Override 
     public Object getItem(int position) { 
      return position; 
     } 

     //@Override 
     public long getItemId(int position) { 
      return position; 
     } 

     //@Override 
     public View getView(final int position, View convertView, ViewGroup parent) { 
      View view = convertView; 
      final ViewHolder holder; 
      if (convertView == null) { 
       view = mInflater.inflate(R.layout.mainpage_list,parent, false); 
       holder = new ViewHolder(); 
       holder.title_text = (TextView) view.findViewById(R.id.title_text); 
       holder.des_text = (TextView) view.findViewById(R.id.des_text); 
       holder.lat_text = (TextView) view.findViewById(R.id.lat_text); 
       holder.long_text = (TextView) view.findViewById(R.id.long_text); 


       view.setTag(holder); 
      } else { 
       holder = (ViewHolder) view.getTag(); 
      } 

      holder.title_text.setText(""+title.get(position)); 

      holder.des_text.setText(""+Html.fromHtml(start_time.get(position))); 

      holder.lat_text.setText(""+Html.fromHtml(latitude.get(position))); 

      holder.long_text.setText(""+Html.fromHtml(longitude.get(position))); 

     return view; 
     } 
    } 
} 

Answer 1

ListView list = (ListView) findViewById(R.id.list); 
title = new ArrayList<String>(); 
latitude = new ArrayList<String>(); 
longitude = new ArrayList<String>(); 

Я надеюсь, что вы забыли ArrayList<String> start_time;
Так,

ListView list = (ListView) findViewById(R.id.list); 
title = new ArrayList<String>(); 
latitude = new ArrayList<String>(); 
longitude = new ArrayList<String>(); 
start_time= new ArrayList<String>(); // <-- This Line