的Android GridView的錯誤

Question

我有GridView的，這cintains 60種元素的應用程序...這裏是ImageAdapter的代碼，其延伸BaseAdapter顯示他們...

public class ImageAdapter extends BaseAdapter { 
private Context context; 
private final String[] mobileValues; 

public ImageAdapter(Context context, String[] mobileValues) { 
    this.context = context; 
    this.mobileValues = mobileValues; 
} 

public View getView(int position, View convertView, ViewGroup parent) { 

    LayoutInflater inflater = (LayoutInflater) context 
      .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 

    View gridView; 

    if (convertView == null) { 

     gridView = new View(context); 

     // get layout from mobile.xml 
     gridView = inflater.inflate(R.layout.mobile, null); 

     // set value into textview 
     TextView textView = (TextView) gridView 
       .findViewById(R.id.grid_item_label); 
     textView.setText(mobileValues[position]); 

     // set image based on selected text 
     ImageView imageView = (ImageView) gridView 
       .findViewById(R.id.grid_item_image); 

     String mobile = mobileValues[position]; 

     if (mobile.equals("Alfa Romeo")) { 
      imageView.setImageResource(R.drawable.alfa); 
     } else if (mobile.equals("Aston Martin")) { 
      imageView.setImageResource(R.drawable.aston); 
     } else if (mobile.equals("Audi")) { 
      imageView.setImageResource(R.drawable.audi); 
     } else if (mobile.equals("Bentley")) { 
      imageView.setImageResource(R.drawable.bentley); 
     } else if (mobile.equals("BMW")) { 
      imageView.setImageResource(R.drawable.bmw); 
     } else if (mobile.equals("Bugatti")) { 
      imageView.setImageResource(R.drawable.bugatti); 
     } else if (mobile.equals("Buick")) { 
      imageView.setImageResource(R.drawable.buick); 
     } else if (mobile.equals("Cadillac")) { 
      imageView.setImageResource(R.drawable.cadillac); 
     } else if (mobile.equals("Chery")) { 
      imageView.setImageResource(R.drawable.chery); 
     } else if (mobile.equals("Chevrolet")) { 
      imageView.setImageResource(R.drawable.chevrolet); 
     } else if (mobile.equals("Chrysler")) { 
      imageView.setImageResource(R.drawable.chrysler); 
     } else if (mobile.equals("Citroen")) { 
      imageView.setImageResource(R.drawable.citroen); 
     } else if (mobile.equals("Dacia")) { 
      imageView.setImageResource(R.drawable.dacia); 
     } else if (mobile.equals("Daewoo")) { 
      imageView.setImageResource(R.drawable.daewoo); 
     } else if (mobile.equals("Dodge")) { 
      imageView.setImageResource(R.drawable.dodge); 
     } else if (mobile.equals("Ferrari")) { 
      imageView.setImageResource(R.drawable.ferrari); 
     } else if (mobile.equals("Fiat")) { 
      imageView.setImageResource(R.drawable.fiat); 
     } else if (mobile.equals("Ford")) { 
      imageView.setImageResource(R.drawable.ford); 
     } else if (mobile.equals("Gaz")) { 
      imageView.setImageResource(R.drawable.gaz); 
     } else if (mobile.equals("Holden")) { 
      imageView.setImageResource(R.drawable.holden); 
     } else if (mobile.equals("Honda")) { 
      imageView.setImageResource(R.drawable.honda); 
     } else if (mobile.equals("Hyindai")) { 
      imageView.setImageResource(R.drawable.hyundai); 
     } else if (mobile.equals("Infinity")) { 
      imageView.setImageResource(R.drawable.infiniti); 
     } else if (mobile.equals("Jaguar")) { 
      imageView.setImageResource(R.drawable.jaguar); 
     } else if (mobile.equals("Jeep")) { 
      imageView.setImageResource(R.drawable.jeep); 
     } else if (mobile.equals("Kia")) { 
      imageView.setImageResource(R.drawable.kia); 
     } else if (mobile.equals("Lada")) { 
      imageView.setImageResource(R.drawable.lada); 
     } else if (mobile.equals("Lamborghini")) { 
      imageView.setImageResource(R.drawable.lamborghini); 
     } else if (mobile.equals("Lancia")) { 
      imageView.setImageResource(R.drawable.lancia); 
     } else if (mobile.equals("Land Rover")) { 
      imageView.setImageResource(R.drawable.land); 
     } else if (mobile.equals("Lexus")) { 
      imageView.setImageResource(R.drawable.lexus); 
     } else if (mobile.equals("Lotus")) { 
      imageView.setImageResource(R.drawable.lotus); 
     } else if (mobile.equals("Maserati")) { 
      imageView.setImageResource(R.drawable.maserati); 
     } else if (mobile.equals("Maybach")) { 
      imageView.setImageResource(R.drawable.maybach); 
     } else if (mobile.equals("Mazda")) { 
      imageView.setImageResource(R.drawable.mazda); 
     } else if (mobile.equals("Mercedes")) { 
      imageView.setImageResource(R.drawable.mercedes); 
     } else if (mobile.equals("Mercuri")) { 
      imageView.setImageResource(R.drawable.mercury); 
     } else if (mobile.equals("Mini")) { 
      imageView.setImageResource(R.drawable.mini); 
     } else if (mobile.equals("Mitshubishi")) { 
      imageView.setImageResource(R.drawable.mitsubishi); 
     } else if (mobile.equals("Nissan")) { 
      imageView.setImageResource(R.drawable.nissan); 
     } else if (mobile.equals("Opel")) { 
      imageView.setImageResource(R.drawable.opel); 
     } else if (mobile.equals("Pagani")) { 
      imageView.setImageResource(R.drawable.pagani); 
     } else if (mobile.equals("Peugeot")) { 
      imageView.setImageResource(R.drawable.peugeot); 
     } else if (mobile.equals("Pontiac")) { 
      imageView.setImageResource(R.drawable.pontiac); 
     } else if (mobile.equals("Porshe")) { 
      imageView.setImageResource(R.drawable.porshe); 
     } else if (mobile.equals("Renault")) { 
      imageView.setImageResource(R.drawable.renault); 
     } else if (mobile.equals("Rolls Royce")) { 
      imageView.setImageResource(R.drawable.rolls); 
     } else if (mobile.equals("Rover")) { 
      imageView.setImageResource(R.drawable.rover); 
     } else if (mobile.equals("Saab")) { 
      imageView.setImageResource(R.drawable.saab); 
     } else if (mobile.equals("Scion")) { 
      imageView.setImageResource(R.drawable.scion); 
     } else if (mobile.equals("Seat")) { 
      imageView.setImageResource(R.drawable.seat); 
     } else if (mobile.equals("Skoda")) { 
      imageView.setImageResource(R.drawable.skoda); 
     } else if (mobile.equals("Sssang Young")) { 
      imageView.setImageResource(R.drawable.ssang); 
     } else if (mobile.equals("Subaru")) { 
      imageView.setImageResource(R.drawable.subaru); 
     } else if (mobile.equals("Suzuki")) { 
      imageView.setImageResource(R.drawable.suzuki); 
     } else if (mobile.equals("Toyota")) { 
      imageView.setImageResource(R.drawable.toyota); 
     } else if (mobile.equals("Vauxhall")) { 
      imageView.setImageResource(R.drawable.vauxhall); 
     } else if (mobile.equals("Volkswagen")) { 
      imageView.setImageResource(R.drawable.volkswagen); 
     } else if (mobile.equals("Volvo")) { 
      imageView.setImageResource(R.drawable.volvo); 
     } else { 
      imageView.setImageResource(R.drawable.acura); 
     } 

    } else { 
     gridView = (View) convertView; 
    } 

    return gridView; 
} 

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

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

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

問題是 - 當我滾動網格視圖下來 - 它開始顯示元素從一開始....什麼是我的錯誤？

Answer 1

您未正確使用convertView。適配器中的視圖被回收以防止額外的視圖創作。如果視圖被回收，則通過convertView傳遞。但重要的一點是，該觀點可能以前屬於不同的項目。如果您沒有再次填充視圖，它將包含不正確的數據 - 屬於某個已回收的其他項目的數據。

的getView方法應該包含這樣的事情：

public View getView(int position, View convertView, ViewGroup parent) { 
    View gridView; 

    if (convertView == null) { 
     // create new gridView here 
    } else { 
     // recycle the convertView 
     gridView = (View) convertView; 
    } 

    // fill the gridView here 

    return gridView; 
}