打開時旋轉微調器中的箭頭

Question

我在佈局上有微調。微調有箭頭。當微調器關閉箭頭顯示從右到左。

當我打開微調和顯示dropdownview，我想旋轉箭頭。

有必要改變箭頭的方向，取決於狀態微調器 我該怎麼辦？謝謝

Answer 1

更改適配器中佈局的背景。請參閱下面的代碼：

public class adapterActivity extends ArrayAdapter<DTO_MCode> { 

    public adapterActivity(Context context, int textViewResourceId) { 
     super(context, textViewResourceId); 
     // TODO Auto-generated constructor stub 
    } 

    // Note: for combobox 
    @Override 
    public View getDropDownView(int position, View convertView, 
      ViewGroup parent) { 
     // TODO Auto-generated method stub 
     return getViewChung(position, convertView, parent, true); 
    } 

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

    public View getViewChung(int position, View convertView, 
      ViewGroup parent, boolean drop) { 
     // TODO Auto-generated method stub 
     View v = convertView; 
     ViewWraper mwp; 

     if (v == null) { 
      LayoutInflater l = getLayoutInflater(); 
      v = l.inflate(R.layout.layoutcomboxe, null); 
      mwp = new ViewWraper(v); 
      v.setTag(mwp); 
     } else { 

      mwp = (ViewWraper) convertView.getTag(); 
     } 
     LinearLayout layout = mwp.getLayoutrow(); 
     if (drop) { 
      layout.setBackgroundResource(R.drawable.down); 
     } else { 
      layout.setBackgroundResource(R.drawable.up); 
     } 

     return v; 
    } 
}