奇怪的致命異常在Android ListView

即時通訊在Android世界相當新，我有一個令人困惑的錯誤，我不能處理。奇怪的致命異常在Android ListView

我有以下的ListView：

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:orientation="vertical" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"> 


    <ListView 
     android:id="@+id/listView1" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" > 

    </ListView> 

</LinearLayout>

而這項活動：

package com.study.semesterplaner.vorlesungszeit; 

import java.util.ArrayList; 

import android.app.Activity; 
import android.content.Context; 
import android.os.Bundle; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.BaseAdapter; 
import android.widget.ListView; 
import android.widget.TextView; 

import com.study.constants.IntentConstants; 
import com.study.droid.R; 
import common.vorlesung.Vorlesung; 
import common.vorlesung.VorlesungszeitHaeufigkeit; 
import common.vorlesung.vorlesungszeit.Vorlesungszeit; 

public class VorlesungszeitListActivity extends Activity{ 

    private ListView _listView; 
    private ArrayList<Vorlesungszeit> _vorlesungszeiten; 
    private VorlesungszeitListAdapter _listAdapter; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.list_with_add_button); 

     Vorlesung selectedVorlesung = (Vorlesung) getIntent().getExtras().get(IntentConstants.INTENT_VORLESUNG_DETAILS); 
     _vorlesungszeiten = selectedVorlesung.getVorlesungsZeiten(); 

     _listView = (ListView) findViewById(R.id.listView1); 
     _listAdapter = new VorlesungszeitListAdapter(); 
     _listView.setAdapter(_listAdapter); 
    } 

    private class VorlesungszeitListAdapter extends BaseAdapter{ 

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

     @Override 
     public Object getItem(int position) { 
      return _vorlesungszeiten.get(position); 
     } 

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

     @Override 
     public View getView(int position, View convertView, ViewGroup parent) { 
      View view = convertView; 
      LayoutInflater vi = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
      view = vi.inflate(R.layout.row_three_textviews, null); 
      TextView top = (TextView) view.findViewById(R.id.row_three_textview_ONE); 
      TextView mid = (TextView) view.findViewById(R.id.row_three_textview_TWO); 
      TextView bottom = (TextView) view.findViewById(R.id.row_three_textview_THREE); 

      Vorlesungszeit vZeit = _vorlesungszeiten.get(position); 

      top.setText(vZeit.getTag() + ", " + vZeit.getVorlesungsbeginn() + " - " + vZeit.getVorlesungsende() + " Uhr"); 
      mid.setText("Raum: " + vZeit.getRaum()); 
      bottom.setText(VorlesungszeitHaeufigkeit.getHauefigkeitText(vZeit.getHaeufigkeit())); 

      return view; 
     } 

    } 
}

如果我嘗試啓動這個活動，我得到這個奇怪的例外：

03-17 21:48:38.867: E/AndroidRuntime(8864): FATAL EXCEPTION: main 
03-17 21:48:38.867: E/AndroidRuntime(8864): java.lang.NullPointerException 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.ListView.measureScrapChild(ListView.java:1136) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.ListView.measureHeightOfChildren(ListView.java:1267) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.ListView.onMeasure(ListView.java:1128) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.measureVertical(LinearLayout.java:386) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.measureVertical(LinearLayout.java:386) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.measureVertical(LinearLayout.java:386) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.measureVertical(LinearLayout.java:531) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3257) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.View.measure(View.java:8524) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewRoot.performTraversals(ViewRoot.java:915) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1991) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.os.Handler.dispatchMessage(Handler.java:99) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.os.Looper.loop(Looper.java:150) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at android.app.ActivityThread.main(ActivityThread.java:4293) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at java.lang.reflect.Method.invokeNative(Native Method) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at java.lang.reflect.Method.invoke(Method.java:507) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:849) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:607) 
03-17 21:48:38.867: E/AndroidRuntime(8864):  at dalvik.system.NativeStart.main(Native Method)

我不知道什麼是錯的。我試圖尋找與調試器的故障代碼，但PROGRAMM即使不訪問活動的OnCreate了Methode ...

來源

2012-03-17 user1016853

你能張貼'row_three_textviews.xml'？你正在使用哪種Android版本？ – 2012-03-18 15:51:47

的com.study.droid.R進口犯罪嫌疑人似乎對我

來源

2012-03-17 22:28:00 dldnh

爲什麼？這是R級，我所有的佈局都是定義的... – user1016853 2012-03-18 08:42:42

你不得不爲了這種方式工作。如果您的R類是從您的res目錄及其包含的所有內容生成的，它將具有與您的代碼相同的路徑，並且不必導入它。我可能是錯的，但是我想到了，可能是問題所在。 – dldnh 2012-03-18 09:52:03

我不知道我是否理解你的權利。但是R類與我的代碼不一樣。我的意思是R在gen-folder和src-folder中的代碼。如果我刪除導入，我得到一個編譯錯誤，我必須導入R類。 – user1016853 2012-03-18 10:37:19

奇怪的致命異常在Android ListView

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