打开时旋转微调器中的箭头

Question

我在布局上有微调。微调有箭头。当微调器关闭箭头显示从右到左。

当我打开微调和显示dropdownview，我想旋转箭头。

有必要改变箭头的方向，取决于状态微调器 我该怎么办？谢谢

Answer 1

更改适配器中布局的背景。请参阅下面的代码：

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; 
    } 
}