0

Sherlock ActionBar에 대한 개발을 배우고 있습니다. Sherlock ActionBar를 사용하여 데이터베이스에서 목록보기로 날짜를 채우는 예제 프로그램을 만들었습니다.SherlockFragemtActivity 탭에서 데이터를 목록보기로 채울 수 없습니다.

하나의 작업에서 두 ​​개의 탭을 만들었으므로 세부 정보를 입력하는 데 사용한 첫 번째 탭 (fragment1)이 제대로 작동하지만 목록보기에 데이터를 채워야하는 두 번째 탭 (fragment2)은 올바르지 않습니다. 잘 작동합니다.

public class DBAdapter { 

    DBHelper dbHelper; 
    Context context; 
    SQLiteDatabase db; 
    public static final int DATABASE_VERSION = 1; 

    String DATABASE_NAME = "sampleDB"; 
    String TABLE_NAME = "sample"; 

    String COL_ROWID = "rowid"; 
    String COL_NAME ="name"; 
    String COL_LOCATION = "location"; 

    String CREATE_TABLE = "create table sample(rowid integer primary key autoincrement,name text not null,location text not null) "; 

    public DBAdapter(Context c) { 
     // TODO Auto-generated constructor stub 
     this.context = c; 
     dbHelper = new DBHelper(context); 
    } 

    DBAdapter openDatabase() { 
     db = dbHelper.getWritableDatabase(); 
     return this; 

    } 

    void close() { 
     dbHelper.close(); 
    } 

    long insertRecord(String name, String location) { 
     ContentValues con = new ContentValues(); 
     con.put(COL_NAME, name); 
     con.put(COL_LOCATION, location); 

     return db.insert(TABLE_NAME, null, con); 

    } 

    Cursor getAllRecords(){ 
     String[] columns = {COL_ROWID,COL_NAME,COL_LOCATION}; 
     return db.query(TABLE_NAME, columns, null, null, null, null, null); 

    } 

    class DBHelper extends SQLiteOpenHelper { 

     public DBHelper(Context context) { 
      super(context, DATABASE_NAME, null, DATABASE_VERSION); 
      // TODO Auto-generated constructor stub 
     } 

     @Override 
     public void onCreate(SQLiteDatabase db) { 
      // TODO Auto-generated method stub 
      db.execSQL(CREATE_TABLE); 
     } 

     @Override 
     public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { 
      // TODO Auto-generated method stub 

     } 

    } 


} 

그리고 마지막으로 여기에 내 로그 캣의 출력 DBAdapter.java :

Fragment2.java, 데이타베이스에 대한

public class Fragment2 extends SherlockFragment implements TabListener { 
    private Fragment mFragment; 

    DBAdapter db; 
    Cursor c; 
    ListView list; 
    MyAdapter myAdapter; 
    View view ; 

    Context context; 

    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     // TODO Auto-generated method stub 
     super.onCreate(savedInstanceState); 
     //getActivity().setContentView(R.layout.details_listview); 

     db = new DBAdapter(getActivity()); 
     db.openDatabase(); 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
     // TODO Auto-generated method stub 
     view = inflater.inflate(R.layout.details_listview, null); 
     return view; 
    } 

    @Override 
    public void onActivityCreated(Bundle savedInstanceState) { 
     // TODO Auto-generated method stub 
     super.onActivityCreated(savedInstanceState); 

     list = (ListView)view.findViewById(R.id.listView1); 
      registerForContextMenu(list); 
     updateListView(); 
    } 

    private void updateListView() { 
     // TODO Auto-generated method stub 
     c = db.getAllRecords(); 
     myAdapter = new MyAdapter(); 
     list.setAdapter(myAdapter); 
    } 

    @Override 
    public void onTabSelected(Tab tab, FragmentTransaction ft) { 
     // TODO Auto-generated method stub 

     mFragment = new Fragment2();   
      ft.add(android.R.id.content, mFragment); 
      ft.attach(mFragment); 
    } 

    @Override 
    public void onTabUnselected(Tab tab, FragmentTransaction ft) { 
     // TODO Auto-generated method stub 
     ft.remove(mFragment); 
    } 

    @Override 
    public void onTabReselected(Tab tab, FragmentTransaction ft) { 
     // TODO Auto-generated method stub 

    } 

    class MyAdapter extends BaseAdapter{ 

     Context context; 

     @Override 
     public int getCount() { 
      // TODO Auto-generated method stub 
      return c.getCount(); 
     } 

     @Override 
     public Object getItem(int arg0) { 
      // TODO Auto-generated method stub 
      return null; 
     } 

     @Override 
     public long getItemId(int arg0) { 
      // TODO Auto-generated method stub 
      return 0; 
     } 

     @Override 
     public android.view.View getView(int position, android.view.View conview, 
       ViewGroup arg2) { 
      LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
      conview = inflater.inflate(R.layout.customllistview, null); 

      TextView t1 = (TextView)conview.findViewById(R.id.idtextView); 
      TextView t2 = (TextView)conview.findViewById(R.id.nametextView); 
      TextView t3 = (TextView)conview.findViewById(R.id.locationtextView); 

      c.moveToPosition(position); 

      String id = c.getString(0); 
      String name = c.getString(1); 
      String location = c.getString(2); 

      t1.setText("row id: "+id); 
      t2.setText("name :"+name); 
      t3.setText("location :"+location); 


      return conview; 
     } 

    } 

} 

, 데이타베이스 어댑터 :

은 내 코드에서 봐 주시기 바랍니다 :

07-22 18:54:16.684: E/AndroidRuntime(1204): FATAL EXCEPTION: main 
07-22 18:54:16.684: E/AndroidRuntime(1204): java.lang.NullPointerException 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at com.example.sherlocklistview.Fragment2$MyAdapter.getView(Fragment2.java:111) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.AbsListView.obtainView(AbsListView.java:1430) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.ListView.measureHeightOfChildren(ListView.java:1216) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.ListView.onMeasure(ListView.java:1127) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.View.measure(View.java:8313) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:701) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:311) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.View.measure(View.java:8313) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.View.measure(View.java:8313) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.View.measure(View.java:8313) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.LinearLayout.measureVertical(LinearLayout.java:531) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.View.measure(View.java:8313) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.View.measure(View.java:8313) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.View.measure(View.java:8313) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.ViewRoot.performTraversals(ViewRoot.java:839) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1859) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.os.Handler.dispatchMessage(Handler.java:99) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.os.Looper.loop(Looper.java:123) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at android.app.ActivityThread.main(ActivityThread.java:3683) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at java.lang.reflect.Method.invokeNative(Native Method) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at java.lang.reflect.Method.invoke(Method.java:507) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597) 
07-22 18:54:16.684: E/AndroidRuntime(1204):  at dalvik.system.NativeStart.main(Native Method) 

친절하게 제 문제에 대한 해결책을 제공해주십시오.

+1

코드에 다른 문제가 있는지 확실하지 않지만 'MyAdapter' 내부의'context' 변수가 null입니다. – Vikram

+0

@Vikram, 맞습니다. MyAdapter에 인수를 추가하여 작동하게했습니다. – Seenu69

답변

0

Fragment2.java 파일에서 111 행이 정확히 무엇인지에 대한 정보를 제공하십시오 (가져 오기 행 번호를 고려하여).
Fragment2.java의 MyAdapter에서 컨텍스트 변수를 확인하십시오. 아무 곳에서도 초기화되지 않은 것처럼 보입니다.

+0

Blow는 111 행의 코드입니다. LayoutInflater inflater = (LayoutInflater) context.getSystemService (Context.LAYOUT_INFLATER_SERVICE); – Seenu69

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