使用自定義simpleCursorAdapter

我想使用自定義adapter.I嘗試訪問列表活動，而不使用任何自定義適配器它是工作良好，但因爲我想添加更多的功能在列表視圖我想實現自定義adapter.Now我已經嘗試過，但我得到一個空的列表視圖沒有數據可見。列表，活動使用自定義simpleCursorAdapter

public class MainActivity extends ListActivity { 

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

     String selection = MediaStore.Audio.Media.IS_MUSIC + " != 0"; 

     String[] projection = { 
        MediaStore.Audio.Media._ID, 
        MediaStore.Audio.Media.ARTIST, 
        MediaStore.Audio.Media.TITLE, 
        MediaStore.Audio.Media.DATA, 
        MediaStore.Audio.Media.DISPLAY_NAME, 
        MediaStore.Audio.Media.DURATION, 

      }; 
      //query 

      musiccursor = this.managedQuery(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI,projection,selection,null,sortOrder); 
      music_column_index = musiccursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA); 


      int a[]= new int[]{R.id.TitleSong,R.id.Artist}; 


      Custom_Adapter adapter = new Custom_Adapter(this,R.layout.music_items, musiccursor, new String[]{MediaStore.Audio.Media.TITLE,MediaStore.Audio.Media.ARTIST} ,a); 

      this.setAdapter(adapter); 

      } 
    }

定製適配器

public class Custom_Adapter extends SimpleCursorAdapter { 


    private Context mContext; 
    private Context appContext; 
    private int layout; 
    private Cursor cr; 
    private final LayoutInflater inflater; 

    public Custom_Adapter(Context context,int layout, Cursor c,String[] from,int[] to) { 
     super(context,layout,c,from,to); 
     this.layout=layout; 
     this.mContext = context; 
     this.inflater=LayoutInflater.from(context); 
     this.cr=c; 
    } 

    @Override 
    public void bindView(View view, Context context, Cursor cursor) { 
     // TODO Auto-generated method stub 
     super.bindView(view, context, cursor); 
    view=inflater.inflate(layout, null, false); 
     TextView titleS=(TextView)view.findViewById(R.id.TitleSong); 
     TextView artistS=(TextView)view.findViewById(R.id.Artist); 
     int Title_index; 
     int Artist_index; 
     cursor.moveToFirst(); 
     while(cursor.isLast()){ 

      Title_index=cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME); 
      Artist_index=cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST); 
      titleS.setText(cursor.getString(Title_index)); 
      artistS.setText(cursor.getString(Artist_index)); 
      cr.moveToNext(); 
      } 

    } 

    @Override 
    public View getView(int position, View convertView, ViewGroup parent) { 
     // TODO Auto-generated method stub 

     return convertView; 
    } 
}

來源

2013-07-17 Himanshu Verma

當延伸的光標適配器，你應該覆蓋的方法bindView和newView。 bindView方法用於將所有數據綁定到給定視圖，例如在TextView上設置文本。 newView方法用於擴充新視圖並將其返回，此時不會將任何數據綁定到視圖。大多數適配器使用getView函數，但在擴展遊標適配器時，應該使用bindView和newView。

public class Custom_Adapter extends SimpleCursorAdapter { 

      private Context mContext; 
      private Context appContext; 
      private int layout; 
      private Cursor cr; 
      private final LayoutInflater inflater; 

      public Custom_Adapter(Context context,int layout, Cursor c,String[] from,int[] to) { 
       super(context,layout,c,from,to); 
       this.layout=layout; 
       this.mContext = context; 
       this.inflater=LayoutInflater.from(context); 
       this.cr=c; 
      } 

      @Override 
      public View newView (Context context, Cursor cursor, ViewGroup parent) { 
        return inflater.inflate(layout, null); 
      } 

      @Override 
      public void bindView(View view, Context context, Cursor cursor) { 
       super.bindView(view, context, cursor); 
       TextView titleS=(TextView)view.findViewById(R.id.TitleSong); 
       TextView artistS=(TextView)view.findViewById(R.id.Artist); 

       int Title_index=cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME); 
       int Artist_index=cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.ARTIST); 

       titleS.setText(cursor.getString(Title_index)); 
       artistS.setText(cursor.getString(Artist_index)); 

      } 

    }

來源

2013-07-17 20:08:01 Bobbake4

我能夠在列表視圖中獲取數據，但只有第一行數據出現在所有rows.Check我更新的問題。 –

我有點困惑你改變了什麼，但你應該切換到上面提到的兩種方法。無論哪種方式，我認爲你遇到的問題是你沒有移動光標索引。在將數據從光標中拉出之前，應該調用cr.moveToPosition（position）。切換newView bindView方法以減少需要膨脹新視圖，因爲您不檢查convertView是否爲空並重用它。 – Bobbake4

您還正在打印列的索引，而不是存儲在光標中的實際數據。 – Bobbake4

你最好在你的customadaptergetview功能寫這幾行代碼。它適用於我，並會爲你工作，這很簡單。

if (convertView == null) { 
    music_column_index = myCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DISPLAY_NAME); 
    myCursor.moveToPosition(position); 
    id = myCursor.getString(music_column_index); 
    music_column_index = myCursor.getColumnIndexOrThrow(MediaStore.Audio.Media.SIZE); 
    myCursor.moveToPosition(position); 
    id += " Size(KB):" + myCursor.getString(music_column_index); 
    Log.d("TAG", "id::" + id); 
    tv.setText(id); 
} else 
    tv = (TextView) convertView; 
    return tv; 
}

來源

2014-04-22 06:37:34 zek

嗯，我看不出這個解決方案有多幹淨 –

使用自定義simpleCursorAdapter

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